Surgery Encyclopedia

limited since the patient is immobilized and sedated ment at home with the implanted device. Complete recov- during treatment. ery of the heart has been demonstrated in 5–15% of pa- tients being supported as a bridge to organ transplantation. Ease of insertion for placement in the aorta makes the intra-aorta balloon pump (IABP) the most often used Pulsatile paracorporeal mechanical circulatory sup- ventricular assist device. Specialty care centers provide port devices provide pulsatile support for the left or right this service in the cardiac catheterization laboratory, ventricle, or both. Cannulation of the left or right atrium, Mechanical circulation support operating room, critical care unit, and emergency room. along with the aorta or pulmonary artery, respectively, Secondary-care-level hospitals can also employ this tech- requires a surgical approach. The heart is emptied of nology. Well-trained staff are required to monitor equip- blood by the assist device, so there is little ejection from ment at regular intervals and troubleshoot problems. the body’s heart. Left ventricular (the lower left chamber of the heart) Removal of the device occurs at the time of cardiac support with the IABP reduces the workload of the heart transplant, unless the body’s heart has healed during sup- and increases blood flow to the vital organs. The balloon port. Anticoagulation is achieved by low doses of drugs. inflates during diastole (the filling phase of the heart) to Some patients regain mobility while assisted by these deliver increased oxygen-saturated blood to the heart; devices. blood flow is also increased to the arteries. Deflation of the balloon occurs prior to systole (the emptying phase Destination therapies of the heart). Destination therapies intended to supplement or per- With recovery of the heart, the IABP device is timed manently replace the body’s heart are provided by chron- to inflate with every second or third heart beat. The ic implantation of the mechanical circulatory support catheter is removed, non-surgically, when the heart can system. For example, total artificial hearts (TAH) replace sustain blood pressure and systemic blood flow. Antico- the body’s heart. Upon removal of the native heart, the agulation is achieved with minimal drugs throughout the TAH will be attached to the major blood vessels, thereby treatment. The device can be in place up to several supplying blood pressure and flow to both the pul- weeks, but duration is limited because the patient must monary and systemic circulation. Destination therapies be immobilized during the treatment. are currently in clinical trials, offering those patients not Centrifugal pumps are able to provide support to eligible for organ transplantation a promising future. one or both ventricles. Blood is removed from the left or right atrium (upper chamber) and returned to the aorta or Preparation pulmonary artery, respectively; therefore, surgery is re- General anesthetic is given to the patient if a chest quired to place the device. Specialty care facilities have incision will be used to expose the heart or if blood ves- the staff and equipment to provide treatment to heart fail- sels need to be exposed. Sedation with local anesthetic is ure patients with the use of mechanical circulatory sup- sufficient if the vessels can be accessed with a needle port devices. Postoperative care in critical care units re- stick. Cardiac monitoring will be performed, including quires continuous monitoring by dedicated staff. electrocardiograph and cardiovascular pressures. Blood The cannulae are passed through the chest wall to tests prior to surgery are used to measure blood elements attach to a pump that draws blood into the device and and electrolytes. Once all sterile connections are com- propels it to the arterial cannula. As the heart recovers, plete, the physician will request that mechanical circula- blood flow is decreased from the centrifugal pump until tory support be initiated. Adjustments may be frequent the device can be removed. An anticoagulant drug is de- initially, but decrease as the patient stabilizes. livered continuously during treatment with a centrifugal pump, and patient immobilization limits the length of Normal results support to several weeks. Once stable following device implant, the patient is Intermediate- to long-term support devices cared for in the intensive care unit (ICU). Any change in patient status is reported to the physician. Around-the- When short-term support devices such as ECMO, clock bedside care is provided by trained nursing staff. IABP, and the centrifugal pump are ineffective to sustain the patient to recovery or organ transplantation, a medi- These patients are very ill when they require device um- or long-term device is required. An advantage of implant, often suffering from multi-system organ failure treatment with a medium- to long-term device is that it al- as a result of poor blood flow. The long-term survival is lows the patient to be mobile. In some instances, patients superior at one year when compared to medical treat- have been able to leave the hospital for continued treat- ment alone. Patients that continue to improve on inter- GALE ENCYCLOPEDIA OF SURGERY 943

Mechanical ventilation Anticoagulant—Pharmaceutical to prevent clot- Mechanical debridement see Debridement KEY TERMS ting proteins and platelets in the blood to be acti- vated to form a blood clot. Mechanical ventilation Cannulae—Tubes that provide access to the blood once inserted into the heart or blood vessels. Cardiac—Of or relating to the heart. Definition Mechanical ventilation is the use of a mechanical Cardiac output—The liter per minute blood flow device (machine) to inflate and deflate the lungs. generated by contraction of the heart. Cardiopulmonary bypass—Diversion of blood Purpose flow away from the right atrium and return of blood beyond the left ventricle to bypass the heart Mechanical ventilation provides the force needed to and lungs. deliver air to the lungs in a patient whose own ventilato- ry abilities are diminished or lost. Description mediate-, long-term, and TAH increase in activity level and begin a regular exercise program. Eventually, with Breathing requires the movement of air into and out proper training about device maintenance, they are able of the lungs. This is normally accomplished by the di- to leave the hospital to live at home, returning to a nor- aphragm and chest muscles. A variety of medical condi- mal lifestyle, until further medical treatment is required. tions can impair the ability of these muscles to accom- plish this task, including: Resources • muscular dystrophies BOOKS • motor neuron disease, including ALS DeBakey, Michael, and Antonio M. Gotto. The New Living Heart. Holbrook: Adams Media Corporation, 1997. • damage to the brain’s respiratory centers Gravelee, Glenn P., Richard F. Davis, Mark Kurusz, and Joe R. • polio Utley. Cardiopulmonary Bypass: Principles and Practice, • myasthenia gravis Second Edition. Philadelphia: Lippincott Williams & Wilkins, 2000. • myopathies affecting the respiratory muscles PERIODICALS • scoliosis Stevenson, Lynne W., et al. “Mechanical Cardiac Support Mechanical ventilation may also be used when the 2000: Current Applications and Future Trial Design.” The airway is obstructed, especially at night in sleep apnea. Journal of Heart and Lung Transplantation (January 2001): 1–38. Mechanical ventilation may be required only at night, during limited daytime hours, or around the clock, de- ORGANIZATIONS pending on the patient’s condition. Some patients require Commission on Accreditation of Allied Health Education Pro- mechanical ventilation only for a short period, during re- grams. 1740 Gilpin St., Denver, CO 80218. (303) 320- covery from traumatic nerve injury, for instance. Others 7701. <http://www.caahep.org>. require it chronically, and may increase the number of Extracorporeal Life Support Organization (ELSO). 1327 Jones Dr., Ste. 101, Ann Arbor, MI 48105. (734) 998-6600. hours required over time as their disease progresses. <http://www.elso.med.umich.edu/>. Mechanical ventilation is not synonymous with the Joint Commission on Accreditation of Health Organizations. use of an oxygen tank. Supplemental oxygen is used in One Renaissance Boulevard, Oakbrook Terrace, IL 60181. patients whose gas exchange capacity has diminished, (630) 792-5000. <http://www.jcaho.org/>. either through lung damage or obstruction of a major air- OTHER way. For these patients, the muscles that deliver air work “Spare Hearts: A Houston Chronicle Four-Part Series.” The well, but too little oxygen can be exchanged in the re- Houston Chronicle October 1997. <http://www.chron. maining lung, and so a higher concentration is supplied com/content/chronicle/metropolitan/heart/index.html>. with each breath. By the same token, many patients who require mechanical ventilation do not need supplemental Allison Joan Spiwak, BS, CCP oxygen. Their gas exchange capacity is normal, but they 944 GALE ENCYCLOPEDIA OF SURGERY

cannot adequately move air into and out of the lungs. In be preferred by patients who find masks uncomfortable fact, excess oxygen may be dangerous, since it can sup- or unsightly. Some patients feel ventilation through a press the normal increased respiration response to excess “trach tube” is more reassuring. Tracheostomy is also the carbon dioxide in the lungs. preferred option for most patients with swallowing diffi- culties. The potential to choke and suffocate on improp- Mechanical ventilation Mechanical ventilation systems come in a variety of erly swallowed food is avoided with a tracheostomy. forms. Almost all systems use a machine called a venti- lator that pushes air through a tube for delivery to the pa- Tracheostomies may require more frequent suction- tient’s airways. The air may be delivered through a nasal ing of airway secretions, produced in response to the or face mask, or through an opening in the trachea presence of the tube and the inflatable cuff that some pa- (windpipe), called a tracheostomy. Much rarer are sys- tients require to hold it in place. The risk of infection is tems that rhythmically change the pressure around a pa- higher, and air must be carefully humidified and cleaned, tient’s chest when the pressure is low, air flows into the since these functions are not being served by the nasal lungs, and when it increases, air flows out. passages. Tracheostomies do not prevent speech, despite misinformation to the contrary that even some doctors Ventilators believe. Speech requires passage of air around the trach tube, which can occur either with an uncuffed tube, or Ventilators can either deliver a set volume with each with the presence of a special valve that allows air pas- cycle, or can be set to a specific pressure regimen. Both sage past the cuff. are in common use. Volume ventilator settings are ad- justable for total volume delivered, timing of delivery, Noninvasive interfaces come in a variety of forms. A and whether the delivery is mandatory or determined by simple mouthpiece may be used, which a patient bites the patient’s initial inspiratory effort. down on to seal the lips around the tube as the pressure cycle delivers a breath. Most masks are individually fit- Pressure ventilators deliver one of two major pres- ted to the patient’s face, and held in place with straps. A sure regimens. Continuous positive airway pressure tight fit is essential, since the pressure must be delivered (CPAP) delivers a steady pressure of air, which assists to the patient’s lungs, and not be allowed to blow out the the patient’s inspiration (breathing in) and resists expira- sides of the mask. Masks may be used around the clock. tion (breathing out). The pressure of CPAP is not suffi- Nasal masks do not prevent speech, though the tone may cient to completely inflate the lungs; instead its purpose change. Oral or full-face masks do interfere with speech, is to maintain an open airway, and for this reason it is and are typically used at night or intermittently through- used in sleep apnea, in which a patient’s airway closes out the day, for patients who do not need continuous frequently during sleep. ventilation assistance. Bilevel positive airway pressure (BiPAP) delivers a higher pressure on inspiration, helping the patient obtain Other alternatives a full breath, and a low pressure on expiration, allowing the patient to exhale easily. BiPAP is a common choice The iron lung was an early mechanical ventilation for neuromuscular disease. device, and is still in use in some hospitals. The patient’s head remains outside of it, while the interior depressur- The choice of ventilator type is partly determined by izes. This allows air to push in to the lungs. Repressuriz- the knowledge and preferences of the treating physician. ing deflates the lungs again. Settings are adjusted to maintain patient comfort and ap- propriate levels of oxygen and carbon dioxide in the blood. A device that works on the same principle is the chest shell (something like a turtle’s shell swung around Masks vs. tracheostomy to the front). The pneumobelt applies pressure to deflate, and relaxes it to allow inflation. A rocking bed is used Delivery of air from a ventilator may be either for nighttime ventilation. Tilting the head of the bed through a mask firmly held to the face, or through a tube down deflates the lungs by allowing the abdominal con- inserted into the trachea toward the bottom of the throat. tents to press against the diaphragm. Reversing the angle A mask interface is called noninvasive ventilation, while reverses the process, allowing inflation. a tracheostomy tube is called invasive ventilation. Until the mid-1990s, invasive ventilation was the Preparation option used by virtually all patients requiring long-term mechanical ventilation. For some patients, tracheostomy Patients with diseases in which mechanical ventila- continues to be a preferred option. It is commonly used tion may be required are advised to learn as much as when 24-hour ventilation assistance is required, and may possible about treatment options before they become GALE ENCYCLOPEDIA OF SURGERY 945

Meckel’s diverticulectomy necessary. In particular, it is important to learn about and Muscular Dystrophy Association. 3300 E. Sunrise Drive Tucson, AZ 85718. (800) 572-1717. <http://www.mdausa.org>. make decisions about invasive vs. noninvasive ventila- tion before the time comes. Many patients who begin Richard Robinson ventilation with emergency tracheostomy have a difficult time switching to noninvasive ventilation later on (though it is certainly possible). It is often a good idea to try out different masks and other interfaces before their need arises, and to have these fitted in preparation for a planned transition to the ventilator. Patients can find support groups and other Meckel’s diverticulectomy sources of information to learn more about the options Definition and the features of each means of ventilation. Patients Meckel’s diverticulectomy is a surgical procedure may have to help educate their doctors if they are not fa- that isolates and removes an abnormal diverticulum miliar with noninvasive options. (Meckel’s diverticulum) or pouch, as well as surrounding Patients with neuromuscular disease may have as tissue, in the lining of the small intestine. It is performed much or more need for a deep cough as they do for ven- to remove an obstruction, adhesions, infection, or in- tilatory assistance, and many patients who undergo flammation. emergency tracheostomy do so because their airways have become clogged with mucus build up. Physical Purpose therapy cough assistance and a cough assist device are important options for full respiratory health. Meckel’s diverticulum is an intestinal diverticulum (pouch) that results from the inability of the vitteline (um- bilical) duct to close at five weeks of embryonic develop- Normal results ment. The vitteline duct is lined with layers of intestinal tissue containing cells that can develop into many differ- Mechanical ventilation is a life saver, and provides ent forms, called pluripotent cells. Meckel’s diverticulum comfort and confidence to patients who require it. Proper is a benign congenital condition that has no symptoms for ventilation restores levels of oxygen and carbon dioxide some people, and develops complications in others. in the blood, improving sleep at night and increasing the ability to engage in activities during the day. When com- Ninety percent of diverticula are close to the ileoce- bined with proper respiratory hygiene, it can prolong life cal valve in the upper intestine, and tissue made up pre- considerably. Patients with progressive diseases such as dominantly of gastric and pancreatic cells is thought to ALS may wish to consider end-of-life decisions before cause chemical changes in the mucosa, or lining of the commencing mechanical ventilation, or before the abili- intestines. ty to communicate is lost. The most common cells found in the mucosa of di- verticula are gastric cells (present in 50% of all Meckel’s Resources diverticulum cases). The highly acidic secretions of gas- BOOKS tric tissue may cause the early symptoms of Meckel’s di- Bach, John R. Noninvasive Mechanical Ventilation. Hanley and verticulum. The alkaline secretions of pancreatic tissue Belfus, 2002. are also thought to be a source of diverticula inflamma- Kinnear, W. J. M. Assisted Ventilation at Home: A practical tion in a small number—about 5%—of cases. Guide. Oxford: Oxford Medical Publications, 1994. Inflammation of the diverticula or infection of the PERIODICALS intestines around the diverticula results in a condition Robinson, R. “A Breath of Fresh Air.” Quest Magazine 5 (Oc- known as diverticulitis, which may be treated with an- tober 1998) [cited July 1, 2003]. <http://www.mdausa.org/ tibiotics. However, when it is acute and causes obstruc- publications/Quest/q56freshair.html>. tions and bleeding, surgery is the treatment of choice. Robinson, R. “Breathe Easy.” Quest Magazine 5(October 1998) [cited July 1, 2003]. <http://www.mdausa.org/pub- lica tions/Quest/q55breathe.html>. Demographics ORGANIZATIONS Meckel’s diverticulum is present in approximately ALS Association. 27001 Agoura Road, Suite 150 Calabasas 2% of the population. It is the most commonly encoun- Hills, CA 91301-5104. (800) 782-4747. <http://www. tered congenital anomaly of the small intestine. Al- alsa.org>. though the abnormality occurs in both sexes, men have 946 GALE ENCYCLOPEDIA OF SURGERY

Meckel's diverticulectomy Diverticulum Diverticulum Meckel’s diverticulectomy Omentum Incision A. B. Inner layer of mattress sutures C. Inverting closure D. E. During Meckel’s diverticulectomy, the abdomen is opened above the area of the diverticulum, which is exposed along with the bowel (A).The diverticulum is clamped off at the base, and then cut off (B).Two layers of stitches are used to repair the bowel (C and D). (Illustration by GGS Inc.) GALE ENCYCLOPEDIA OF SURGERY 947

Meckel’s diverticulectomy Surgery takes place in a hospital setting by a • Is this surgery necessary or can changing the QUESTIONS WHO PERFORMS THE PROCEDURE AND TO ASK THE DOCTOR WHERE IS IT PERFORMED? diet and medical treatment be just as effec- physician with advanced training in surgery tive? and gastrointestinal surgery. If the surgery is minimally invasive, requiring only small inci- basis, how extensive was the surgery and sions, it may be performed in an outpatient sur- how much of the intestine was removed? gical area of the hospital. • Because this surgery was on an emergency Some surgeons prefer to perform two surgeries, and do more frequent complications with the condition and are not join together the intestinal sections until some heal- more often diagnosed with it. One 15-year study set the ing of the segments has occurred. In this case, a stoma, complication risk of the abnormality at 4.2%. A recent or temporary outlet for tubal connection to the intestines, 10-year study done retrospectively reported an even age is created in the wall of the abdomen where an external distribution for complications of the diverticulum. Ma- appliance, called an ostomy, can receive waste until the lignancy is found in only 0.5–4.9% of patients with com- intestinal sections are rejoined. plications of Meckell’s diverticulum. Diagnosis/Preparation Description The vast majority of Meckel’s diverticulum diag- Open surgery of the intestines is indicated in acute noses are incidental, that is, discovered during barium cases. In the surgery, the intestinal segment containing studies, abdominal surgery for other conditions, or au- the diverticulum, usually the ileum or upper intestines, is topsy. The most common symptom of the condition is removed. After the diverticulum is removed, the healthy intestinal bleeding, which occurs in 25–50% of patients portions of the intestine are joined together. Some debate who have complications. Hemorrhage is the most signifi- exists about whether surgery for asymptomatic Meckel’s cant symptom in children two years old and younger. In- diverticulum found incidentally is recommended. Some testinal obstructions are common, resulting from compli- researchers have shown that preventive removal of the cations of the tissue surrounding the diverticula. Symp- diverticulum is less risky than surgical complications, tomatic Meckel’s diverticulum has symptoms similar to and point to the fact that 6.4% of patients with Meckel’s appendicitis. Lower abdominable pain or diverculitits ac- diverticulum develop complications of the condition counts for 10–20% of cases, and requires careful diagno- over their lifetime. sis to distinguish it from appendicitis. Left untreated, di- verticulitis can lead to perforation of the intestine and Depending on the surgeon’s decision, the operation peritonitis. may be minimal, isolating and then removing the pouch containing the inflammation, or it may be more exten- Patients who have diverticulitis symptoms, such as sive. In the latter cases, surrounding tissue is removed acute abdominal pain are given various imaging tests, in- due to the presence of pervasive inflammation, obstruc- cluding a CT scan, colonoscopy, or a sigmoidoscopy tion, or incarceration in an inguinal hernia (Littre’s her- (view of the lower colon through a tiny video instrument nia). Removing additional tissue is done to prevent re- placed in the rectum). For children, a special chemical currences. Recent studies have demonstrated the feasibil- diagnostic test of sodium Tc-pertechnetate, a radioiso- ity of laparoscopic, or minimally invasive diverticulecto- tope that reacts to the mucosa in the diverticulum, allows my, utilizing small incisions and video imagery via tiny inflammation or infection to be viewed radiographically. cameras. No long-term studies of this procedure have In adult patients, barium studies may help with diagno- been conducted. sis. When acute hemorrhaging is present, MR imaging of blood vessels is an effective diagnostic tool. Surgery is performed under general anesthetic. The small intestine is isolated and the diverticulum is re- If surgery is indicated for Meckel’s diverticulum, an moved, sometimes with a small segment of the in- enema is given (unless contraindicated by complica- testines. Operative techniques are used to conjoin the tions) to completely clear the bowel and avoid infection end sections of the intestines that have been severed. during surgery. 948 GALE ENCYCLOPEDIA OF SURGERY

Aftercare KEY TERMS Intestinal surgery is a serious procedure, and recov- ery may take two weeks. The number of postoperative Diverticulitis—Inflammation or infection of the Mediastinoscopy days spent in the hospital depends on the extent of the diverticula of the intestines. diverticulum surgery and complications of the condition prior to surgery. Barring complications, patients usually Diverticulum—Pouches or bulges of tissue in the stay in the hospital for about one week. Immediately lining of organs or canals that can become infect- after surgery, the patient is observed carefully, and given ed, especially in the intestines and esophagus. intravenous fluids and antibiotics. Surgical catheters, or Littre’s hernia—A Meckel’s diverticulum incarcer- stents, are removed over the next two days, with food by ated in an inguinal hernia. mouth offered once bowel sounds are heard. Merkel’s diverticulum—Tissue faults in the lining of the intestines that are the result of a congenital abnormality originating in the umbilical duct’s Risks failure to close. Largely asymptomatic, the diver- Intestinal surgery has the surgical complications as- ticula in some cases can become infected or ob- sociated with any open surgery. These include lung and structed. heart complications, as well as reactions to medications, Perforation—The rupture or penetration by injury bleeding, and infection. or infection of the lining of an organ or canal that allows infection to spread into a body cavity, as in Normal results peritonitis, the infection of the lining of the stom- ach or intestines. The usual results of this surgery are an end to ob- struction, pain, and infection. Highly successful results include the return of bowel function and daily activities. PERIODICALS Morbidity and mortality rates “Laparoscopy-assisted Resection of Complicated Meckel’s Di- verticulum in Adults.” Surgical Laparoscopy, Endoscopy Patients with complications of Meckel’s diverticu- and Percutaneous Techniques 12(3) (June 1, 2000): 190-4. lum have a 10–12% incidence of early postoperative “Meckel’s Diverticulum.” American Family Physician 61(4) complications such as an intestinal leak, a suture line leak (February 15, 2000). or intra-abdominal abscess. Later complications occur in ORGANIZATIONS about 7% of patients, and include bowel obstructions and International Foundation for Functional Gastrointestinal Disor- intestinal adhesions. The reported mortality rate for ders (IFFGD).P.O. Box 170864, Milwaukee, WI 53217- surgery on patients with symptomatic diverticulum is 8076. (888) 964-2001 or (414) 964-1799. fax: (414) 964- 2–5%. With asymptomatic patients who undergo inciden- 7176. <http://www.iffgd.org>. tal diverticulectomy, both early and late complications National Digestive Diseases Information Clearinghouse. 2 In- occur in 2% of cases, and the mortality rate is 1%. formation Way, Bethesda, Maryland 20892-3570. <http:// www.niddk.nih.gov>. Alternatives OTHER “Meckel’s diverticulectomy.” MedlinePlus <http://www.nlm. Diverticulitis is routinely treated with a change in nih/medlineplus.gov>. diet that includes increasing bulk with high-fiber foods and bulk additives like Metamucil. Recurrent attacks, Nancy McKenzie, Ph.D. perforation, tissue adhesions, or infections are initially treated with antibiotics, a liquid diet, and bed rest. If medical treatment does not clear the complications, emergency surgery may be required. Resources Mediastinoscopy BOOKS Definition Townsend, Courtney M. “Diverticular Disease” In Sabiston Textbook of Surgery 16th ed. W. B. Saunders Company, Mediastinoscopy is a surgical procedure that allows 2001. physicians to view areas of the mediastinum, the cavity be- GALE ENCYCLOPEDIA OF SURGERY 949

Mediastinoscopy WHERE IS IT PERFORMED? • Why is this test needed? WHO PERFORMS QUESTIONS THE PROCEDURE AND TO ASK THE DOCTOR A mediastinoscopy procedure is usually per- formed by a thoracic or general surgeon in a • Is the test dangerous? • What test preparation is required? hospital setting. • How long will the test take? • When will the results be available? • What form of anesthesia will be used? hind the sternum (breastbone) that lies between the lungs. The organs in the mediastinum include the heart and its • Is the surgeon board certified? vessels, the lymph nodes, trachea, esophagus, and thymus. • How many mediastinoscopy procedures has the surgeon performed? Mediastinoscopy is most commonly used to detect or stage cancer. It is also ordered to detect infection, and to • What is the surgeon’s complication rate? confirm diagnosis of certain conditions and diseases of the respiratory organs. The procedure involves insertion of an endotracheal (within the trachea) tube, followed by a small incision in the chest. A mediastinoscope is inserted through Demographics the incision. The purpose of this equipment is to allow the Approximately 130,000 new pulmonary nodules are physician to directly see the organs inside the medi- diagnosed each year in the United States. Of those, half astinum, and to collect tissue samples for laboratory study. are malignant. The majority of pulmonary nodules are diagnosed via mediastinoscopy. Purpose Mediastinoscopy is often the diagnostic method of Description choice for detecting lymphoma, including Hodgkin’s Mediastinoscopy is usually performed in a hospital disease. The diagnosis of sarcoidosis (a chronic lung dis- under general anesthesia. Before the general anesthesia ease) and the staging of lung cancer can also be accom- is administered, local anesthesia is applied to the throat plished through mediastinoscopy. Lung cancer staging while an endotracheal tube is inserted. Once the patient involves a determination of the level or progression of is under general anesthesia, a small incision is made, the cancer into stages. These stages help a physician usually just below the neck or at the notch at the top of study cancer and provide consistent cancer definition the sternum. The surgeon may clear a path and feel the levels and corresponding treatments. They also provide person’s lymph nodes first to evaluate any abnormalities some guidance as to prognosis. The lymph nodes in the within the nodes. Next, the physician inserts the medi- mediastinum are likely to reveal if lung cancer has astinoscope through the incision. The scope is a narrow, spread beyond the lungs. Mediastinoscopy allows a hollow tube with an attached light that allows the sur- physician to observe and extract a sample from the nodes geon to see inside the area. The surgeon can insert tools for further study. Involvement of these lymph nodes indi- through the hollow tube to help perform biopsies. A tis- cates the diagnosis and stage of lung cancer. sue sample from the lymph nodes or a mass can be re- Mediastinoscopy may also be ordered to verify a di- moved and sent for study under a microscope, or to a agnosis that was not clearly confirmed by other methods, laboratory for further testing. such as certain radiographic and laboratory studies. Me- In some cases, tissue sample analysis that shows diastinoscopy may aid in some surgical biopsies of nodes malignancy will suggest the need for immediate surgery or cancerous tissue in the mediastinum. In fact, a surgeon while the person is already prepared and under anesthe- may immediately perform a surgical procedure if a ma- sia. In other cases, the surgeon will complete the visual lignant tumor is confirmed while the patient is undergo- study and tissue removal, and stitch the small incision ing mediastinoscopy. In these cases, the diagnostic exam closed. The person will remain in the surgerical recovery and surgical procedure are combined into one operation. area until the effects of anesthesia have lessened and it is Mediastinoscopy provides a diagnosis in 10–75% of safe to leave the area. The entire procedure should re- cases, depending on histology, location, and size of cancer. quire about an hour, not counting preparation and recov- The false positive rate, however can be as high as 20%. ery time. Studies have shown that mediastinoscopy is a 950 GALE ENCYCLOPEDIA OF SURGERY

safe, thorough, and cost-effective diagnostic tool with • chylothorax (chyle is milky lymphatic fluid in the less risk than some other procedures. pleural space) • air embolism (air bubble) Mediastinoscopy Diagnosis/Preparation • transient hemiparesis (paralysis on one side of the body) Because mediastinoscopy is a surgical procedure, it The usual risks associated with general anesthesia should only be performed when the benefits of the also apply to this procedure. exam’s findings outweigh the risks of surgery and anes- thesia. Individuals who previously had mediastinoscopy Normal results should not receive it again if there is scarring from the In the majority of procedures performed to diagnose first exam. cancer, a normal result indicates the presence of small, Several other medical conditions, such as impaired smooth lymph nodes, and no abnormal tissue, growths, cerebral circulation, obstruction or distortion of the or signs of infection. In the case of lung cancer staging, upper airway, or thoracic aortic aneurysm (abnormal di- results are related to the severity and progression of the lation of the thoracic aorta) may also preclude medi- cancer. astinoscopy. Certain structures in a person’s anatomy that can be compressed by the mediastinoscope may Morbidity and mortality rates complicate these pre-existing medical conditions. Abnormal findings may indicate lung cancer, tuber- Patients are asked to sign a consent form after re- culosis, the spread of disease from one body part to an- viewing the risks of mediastinoscopy and known risks other, sarcoidosis (a disease that causes nodules, usually and reactions to anesthesia. The physician will normally affecting the lungs), lymphoma (abnormalities in the instruct the patient to fast from midnight before the test lymph tissues), and Hodgkin’s disease. until after the procedure is completed. A physician may Complications of mediastinoscopy include bleeding, also prescribe a sedative the night before the exam and pain, and post-procedure infection. These are relatively again before the procedure. Often a local anesthetic will uncommon. Mortality is extremely rare. be applied to the throat to prevent discomfort during placement of the endotracheal tube. Alternatives A less invasive technique is ultrasound. However, it Aftercare is not as specific as mediastinoscopy, and the informa- Following mediastinoscopy, patients will be careful- tion obtained is not as useful in making a diagnosis. ly monitored and watched for changes in vital signs,or Although still performed, there is a decline in the symptoms of complications from the procedure or anes- use of mediastinoscopy as a result of advancements in thesia. The patient may have a sore throat from the endo- computed tomography (CT), magnetic resonance imag- tracheal tube, experience temporary chest pain, and have ing (MRI), and ultrosonography techniques. In addition, soreness or tenderness at the incision site. improved fine-needle aspiration (withdrawing fluid using suction) results of and core-needle biopsy (using a Risks needle to obtain a small tissue sample) investigations, along with new techniques in thoracoscopy (examination Complications from the actual mediastinoscopy pro- of the thoracic cavity with a lighted instrument called a cedure are relatively rare. The overall complication rates thoracoscope) offer additional options in examining in various studies have been reported in the range of masses in the mediastinum. Mediastinoscopy may be re- 1.3–3%. However, the following complications, in de- quired when other methods cannot be used or when they creasing order of frequency, have been reported: provide inconclusive results. • hemorrhage See also Lung biopsy; Thoracic surgery. • pneumothorax (air in the pleural space) Resources • recurrent laryngeal nerve injury, causing hoarseness BOOKS • infection Bland, K.I., W.G. Cioffi, M.G. Sarr, Practice of General • tumor implantation in the wound Surgery. Philadelphia: Saunders, 2001. Fischbach, F. and F. Talaska A Manual of Laboratory and Di- • phrenic nerve injury (injury to a thoracic nerve) agnostic Tests 6th ed. Philadelphia: Lippincott Williams • esophageal injury and Wilkins, 2000. GALE ENCYCLOPEDIA OF SURGERY 951

Medicaid KEY TERMS American College of Surgeons. 633 North St. Clair Street, Chicago, IL 60611-32311. (312) 202-5000, fax: (312) 202- 5001. <[email protected]>. <http://www.facs.org>. Endotracheal—Placed within the trachea, also 10019-4374. (800) 586-4872. <http://www.lungusa.org>. known as the windpipe. American Lung Association. 1740 Broadway, New York, NY American Medical Association. 515 N. State Street, Chicago, Hodgkin’s disease—A malignancy of lymphoid IL 60610. (312) 464-5000, <http://www.ama-assn.org>. tissue found in the lymph nodes, spleen, liver, and Society of Thoracic Surgeons. 633 N. Saint Clair St., Suite bone marrow. 2320, Chicago, IL 60611-3658. (312) 202-5800, fax: 312- Lymph nodes—Small round structures located 202-5801. <[email protected]>. <http://www.sts.org>. throughout the body; contain cells that fight infec- OTHER tions. Creighton University School of Medicine [cited May 14, 2003]. Pleural space—Space between the layers of the <http://medicine.creighton.edu/forpatients/mediast/ pleura (membrane lining the lungs and thorax). mediastin.html>. Harvard University Medical School [cited May 14, 2003]. Sarcoidosis—A chronic disease characterized by <http://www.health.harvard.edu/fhg/diagnostics/medi nodules in the lungs, skin, lymph nodes, and astinoscopy/mediastinoscopy.shtml>. bones; however, any tissue or organ in the body Merck Manual [cited May 14, 2003]. <http://www.merck. may be affected. com/pubs/mmanual/section6/chapter65/65i.htm>. Thymus—An unpaired organ in the mediastinal University of Missouri [cited May 14, 2003]. <http://www. cavity that is important in the body’s immune re- ellisfischel.org/thoracic/testing/mediastinoscopy.shtml>. sponse. L. Fleming Fallon, Jr., M.D., Dr.PH. Grace, P.A., A. Cuschieri, D. Rowley, N. Borley, A. Darzi Clinical Surgery 2nd Edition. London: Blackwell Publishing, 2003. Schwartz, S.I., J.E. Fischer, F.C. Spencer, G.T. Shires, J.M. Daly, J.M. Principles of Surgery 7th edition. New York: Medicaid McGraw Hill, 1998. Definition Townsend, C., K.L. Mattox, R.D. Beauchamp, B.M. Evers, D.C. Sabiston Sabiston’s Review of Surgery 3rd Edition. Medicaid is a federal-state entitlement program for Philadelphia: Saunders, 2001. low-income citizens of the United States. The Medicaid program is part of Title XIX of the Social Security Act PERIODICALS Amendment that became law in 1965. Medicaid offers Beadsmoore C.J., N.J. Screaton. “Classification, Ttaging and federal matching funds to states for costs incurred in Prognosis of Lung Cancer.” European Journal of Radiolo- paying health care providers for serving covered individ- gy 45(1) (2003): 8–17. uals. State participation is voluntary, but since 1982, all Choi, Y.S., Y.M. Shim, J. Kim, K. Kim. “Mediastinoscopy in 50 states have chosen to participate in Medicaid. Patients with Clinical Ctage I Non-small Cell Lung Can- cer.” Annals of Thoracic Surgery 75(2) (2003): 364–6. Detterbeck, F.C., M.M. DeCamp, Jr., L.J. Kohman, G.A. Sil- Description vestri. “Lung cancer. Invasive staging: the guidelines.” Medicaid benefits Chest 123(1 Suppl) (2003): 167S–175S. Falcone F., F. Fois, D. Grosso. “Endobronchial Ultrasound.” Medicaid benefits cover basic health care and long- Respiration 70(2) (2003): 179–94. term care services for eligible persons. About 58% of Sterman, D.H., E. Sztejman, E. Rodriguez, J. Friedberg. “Diag- Medicaid spending covers hospital and other acute care nosis and Staging of ‘Other Bronchial Tumors’.” Chest services. The remaining 42% pays for nursing home and Surgery Clinics of North America 13(1) (2003): 79–94. long-term care. States that choose to participate in Medicaid must ORGANIZATIONS offer the following basic services: American Board of Surgery. 1617 John F. Kennedy Boulevard, Suite 860, Philadelphia, PA 19103. (215) 568-4000, fax: • hospital care, both inpatient and outpatient 215-563-5718. <http://www.absurgery.org>. • nursing home care American Cancer Society. 1599 Clifton Rd. NE, Atlanta, GA 30329. (800) 227-2345, <http://www.cancer.org> . • physician services 952 GALE ENCYCLOPEDIA OF SURGERY

• laboratory and diagnostic x ray services In most cases, persons must be citizens of the Unit- ed States to be eligible for Medicaid, although legal im- • immunizations and other screening, diagnostic, and Medicaid migrants may qualify in some circumstances depending treatment services for children on their date of entry. Illegal aliens are not eligible for • family planning Medicaid, except for emergency care. • health center and rural health clinic services Persons must fit into an eligibility category to re- • nurse midwife and nurse practitioner services ceive Medicaid, even if their income is low. Childless couples and single childless adults who are not disabled • physician assistant services or elderly are not eligible for Medicaid. Participating states may offer the following optional services and receive federal matching funds for them: Medicaid costs • prescription medications Medicaid is by far the government’s most expensive • institutional care for the mentally retarded general welfare program. In 1966, Medicaid accounted • home- or community-based care for the elderly, includ- for 1.4% of the federal budget, but by 2001, its share had ing case management risen to nearly 9%. Combined federal and state spending for Medicaid takes approximately 20 cents of every tax • personal care for the disabled dollar. The federal government covers about 56% of • dental and vision care for eligible adults costs associated with Medicaid. The states pay for the re- Because participating states are allowed to design maining 44%. their own benefits packages as long as they meet federal As of 2001, costs for Medicaid rose at an average minimum requirements, Medicaid benefits vary consid- annual rate of 7.9%. The federal government spent $107 erably from state to state. About half of all Medicaid billion on Medicaid in fiscal year (FY) 1999, a sum that spending covers groups of people and services above the is expected to rise to $159 billion in 2004. The states federal minimum. spent $81 billion to cover Medicaid costs in FY 1999. These costs are projected to increase to $120 billion by Eligibility for Medicaid FY 2004. Medicaid covers three major groups of low-income Although more than half (54%) of all Medicaid ben- Americans: eficiaries are children, most of the money (more than 70%) goes for services for the elderly and disabled. The • All recipients. In 2001, Medicaid covered 44 million single largest portion of Medicaid money pays for long- low-income persons in the United States. term care for the elderly. Only 18% of Medicaid funds • Parents and children. In 2001, Medicaid covered 24 are spent on services for children. million low-income children, approximately one-fifth There are several factors involved in the steep rise of of all children in the United States. It provided cover- Medicaid costs: age to an estimated 9.3 million low-income adults in families with children; most of these low-income adults • The rise in the number of eligible individuals. As the were women. lifespan of most Americans continues to increase, the • The elderly. In 2001, Medicaid covered five million number of elderly individuals eligible for Medicaid adults over the age of 65. Medicaid is the largest single also rises. The fastest-growing age group in the United purchaser of long-term and nursing home care in the States is people over 85. United States. • The price of medical and long-term care. Advances in • The disabled. About 17% of Medicaid recipients are medical technology, including expensive diagnostic blind or disabled. Most of these persons are eligible for imaging tests, cause these costs to rise. Medicaid because they receive assistance through the • The increased use of services covered by Medicaid. Supplemental Security Income (SSI) program. • The expansion of state coverage from the minimum All Medicaid recipients must have incomes and re- benefits package to include optional groups and option- sources below specified eligibility levels. These levels al services. vary from state to state depending on the local cost of living and other factors. For example, in 2001, the feder- Normal results al poverty level (FPL) was determined to be $14,630 for a family of three on the mainland of the United States, The need to contain Medicaid costs is considered but $16,830 in Hawaii and $18,290 in Alaska. one of the most problematic policy issues facing legisla- GALE ENCYCLOPEDIA OF SURGERY 953

Medicaid KEY TERMS Categorically needy—A term that describes certain groups of Medicaid recipients who qualify for the as the reference point to determine Medicaid eligi- bility for certain groups of beneficiaries. The FPL is basic mandatory package of Medicaid benefits. adjusted every year to allow for inflation. There are categorically needy groups that states par- Health Care Financing Administration (HCFA)—A ticipating in Medicaid are required to cover, and federal agency that provides guidelines for the other groups that the states have the option to cover. Medicaid program. Department of Health and Human Service Medically needy—A term that describes a group (DHHS)—It is a federal agency that houses the whose coverage is optional with the states because Centers for Medicare and Medicaid Services, and of high medical expenses. These persons meet cat- distributes funds for Medicaid. egory requirements of Medicaid (they are children Entitlement—A program that creates a legal oblig- or parents or elderly or disabled) but their income ation by the federal government to any person, is too high to qualify them for coverage as categor- business, or government entity that meets the ically needy. legally defined criteria. Medicaid is an entitlement Supplemental Security Income (SSI)—A federal both for eligible individuals and for the states that entitlement program that provides cash assistance decide to participate in it. to low-income blind, disabled, and elderly people. Federal poverty level (FPL)—The definition of In most states, people receiving SSI benefits are eli- poverty provided by the federal government, used gible for Medicaid. tors. In addition, the complexity of the Medicaid system, Pratt, David A., and Sean K. Hornbeck. Social Security and its vulnerability to billing fraud and other abuses, the con- Medicare Answer Book Gaithersburg, MD: Aspen, 2002. fusing variety of the benefits packages available in differ- Stevens, Robert, and Rosemary Stevens. Welfare Medicine in ent states, and the time-consuming paperwork are other America: A Case Study of Medicaid. Somerset, NJ: Trans- problems that disturb both taxpayers and legislators. action Publishers, 2003. Medicaid has increased the demand for health care PERIODICALS services in the United States without greatly impacting Benko, L. B. “Health Hazard. Medicaid Cuts Could Endanger or improving the quality of health care for low-income Patients.” Modern Healthcare 33 (2003): 26–27. Americans. Medicaid is the largest health insurer in the Chaudry, R. V, W. P. Brandon, C. R. Thompson, R. S. Clayton, United States. As such, it affects the employment of sev- and N. B. Schoeps. “Caring for Patients under Medicaid eral hundred thousand health care workers, including Mandatory Managed Care: Perspectives of Primary Care health care providers, administrators, and support staff. Physicians.” Qualitative Health Research 13 (2003): 37–56. Participation in Medicaid is optional for physicians and Lambert, D., J. Gale, D. Bird, and D. Hartley. “Medicaid Man- nursing homes. Many do not participate in the program aged Behavioral Health in Rural Areas.” Journal of Rural Health 19 (2003): 22–32. because the reimbursement rates are low. As a result, many low-income people who are dependent on Medic- Vastag, B. “Capitol Health Call: Proposal for State Medicaid Autonomy under Fire.” Journal of the American Medical aid must go to overcrowded facilities where they often Association, 289 (2003): 1093–1094. receive substandard health care. ORGANIZATIONS See also Medicare. Health Care Financing Administration. United States Depart- ment of Health and Human Services. 200 Independence Resources Avenue SW, Washington, D.C. 20201. <http://www.hcfa. BOOKS gov>. Albanese, Beverly H. and Heidi Macomber. Medicaid EZ: A Kaiser Commission on Medicaid and the Uninsured. 1450 G Guide to Get Those Nursing Home Bills Paid. New York: Street NW, Suite 250, Washington, DC 20005. (202) 347- iUniverse, 2000. 5270; Fax: (202) 347-5274. <http://www.kff.org>. Conklin, Joan H. Medicare for the Clueless: The Complete National Center for Policy Analysis. 655 15th Street NW, Suite Guide to This Federal Program. New York: Kensington 375, Washington, DC 20005. (202) 628-6671; Fax: (202) Publishing, 2002. 628-6474. <http://www.ncpa.org>. 954 GALE ENCYCLOPEDIA OF SURGERY

United States Department of Health and Human Services. 200 New uses of technology have also raised concerns Independence Avenue SW, Washington, DC 20201. about confidentiality. Confidentiality, or personal priva- <http://www.hhs.gov>. cy, is an important principle related to the chart. Whatev- Medical charts OTHER er system may be in place, it is essential that the health Centers for Medicare and Medicaid Services, US Department care provider protect an individual’s privacy by limiting of Health and Human Services [cited March 14, 2003]. access only to authorized individuals. Generally, physi- <http://cms.hhs.gov/>. cians and nurses write most frequently in the chart. Doc- National Association of State Medicaid Directors [cited March umentation by the clinician who is leading treatment de- 14, 2003]. <http://www.nasmd.org/>. cisions (usually a physician) often focuses on diagnosis National Governor’s Association [cited March 14, 2003]. and prognosis, while the documentation by members of <http://www.nga.org/>. the nursing team generally focuses on individual re- Social Security Administration [cited March 14, 2003]. <http:// sponses to treatment and details of day-to-day progress. www.ssa.gov/>. In many institutions, the medical and nursing staff may complete separate forms or areas of the chart specific to L. Fleming Fallon, Jr, MD, DrPH their disciplines. Other health-care professionals that have access to the chart include physician assistants; social workers; psychologists; nutritionists; physical, occupational, speech, or respiratory therapists; and consultants. It is Medical charts important that the various disciplines view the notes written by other specialties in order to form a complete Definition picture of a person and provide continuity of care. Quali- A medical chart is a confidential document that con- ty assurance and regulatory organizations, legal bodies, tains detailed and comprehensive information on an indi- and insurance companies may also have access to the vidual and the care experience related to that person. chart for specific purposes such as documentation, insti- tutional audits, legal proceedings, or verification of in- Purpose formation for care reimbursement. It is important to know about institutional policies regarding chart access The purpose of a medical chart is to serve as both a in order to ensure the privacy of personal records. medical and legal record of an individual’s clinical sta- tus, care, history, and caregiver involvement. The specif- The medical record should be stored in a pre-desig- ic information contained in the chart is intended to pro- nated, secure area and discussed only in appropriate and vide a record of a person’s clinical condition by detailing private clinical areas. All individuals have a right to view diagnoses, treatments, tests and responses to treatment, and obtain copies of their own records. Special state as well as any other factors that may affect the person’s statutes may cover especially sensitive information such health or clinical state. as psychiatric, communicable disease (i.e., HIV), or sub- stance abuse records. Institutional and government poli- Demographics cies govern what is contained in the chart, how it is doc- umented, who has access, and policies for regulating ac- Every person who has a professional relationship cess to the chart and protecting its integrity and confi- with a health-care provider has a medical record. Be- dentiality. In those cases in which individuals outside of cause most people have such relationships with more the immediate care system must access chart contents, than one health professional or caregiver, most people an individual or personal representative is asked to pro- actually have more than one medical chart. vide permission before records can be released. Individ- uals are often asked to sign these releases so that care- Description givers in new clinical settings may review their charts. The terms medical chart or medical record are a general description of a collection of information on a Diagnosis/Preparation person. However, different clinical settings and systems Training utilize different forms of documentation to achieve this purpose. As technology progresses, more institutions are Thorough training is essential prior to independent adopting computerized systems that aid in clearer docu- use of the medical chart. Whenever possible, a new clini- mentation, enhanced access and searching, and more ef- cian should spend time reviewing the chart to get a sense ficient storage and retrieval of individual records. of organization and documentation format and style. GALE ENCYCLOPEDIA OF SURGERY 955

Medical charts WHERE IS IT PERFORMED? • Progress notes. Includes regular notes on the individ- WHO PERFORMS ual’s status by members of the interdisciplinary care THE PROCEDURE AND team. • Consultations. Contains notes from specialized diag- All members of a health-care team or individuals nosticians or external care providers. • Consents. Includes permissions signed by the individ- who render professional health-care services usu- ual for procedures, tests, or access to chart. May also ally make entries into medical records. Health- contain releases such as the release signed by any per- care records are maintained in hospitals or other son when leaving the facility against medical advice clinical settings and professional offices. Insur- (AMA). ance companies and corporations may maintain limited health-care records or obtain copies of • Flow records. Tracks specific aspects of professional records created by other health-care providers. care that occur on a routine basis, using tables or in a chart format. • Care plans. Documents treatment goals and plans for Training programs for health care professionals often in- future care within a facility or following discharge. clude practice in writing notes or flow charts in mock • Discharge. Contains final instructions for the person medical records. Notes by trainees are often initially and reports by the care team before the chart is closed cosigned by supervisors to ensure accurate and relevant and stored following discharge. documentation and document-appropriate supervision. • Insurance information. Lists health-care benefit cover- age and insurance provider contact information. Operation These general categories may be further divided by Documentation in the medical record begins when an individual facilities for their own purposes. For example, individual enters the care system, which may be a specific a psychiatric facility may use a special section for psy- place such as a hospital or professional office, or a pro- chometric testing, or a hospital may provide sections gram such as a home health-care service. Frequently, a fa- specifically for operations, x ray reports, or electrocar- cility will request permission to obtain copies of previous diograms. In addition, certain details such as allergies or records so that they have complete information on the per- do not resuscitate orders may be displayed prominently son. Although chart systems vary from institution to insti- (for instance, with large colored stickers or special chart tution, there are many aspects of the chart that are univer- sections) on the chart in order to communicate uniquely sal. Frequently used chart sections include the following: important information. It is important for health care • Admission paperwork. Includes legal paperwork such providers to become familiar with the charting systems as a living will or health care proxy, consents for ad- in place at their specific facilities or programs. mission to the facility or program, demographics, and It is important that the information in the chart be contact information. clear and concise, so that those utilizing the record can • History and physical. Contains comprehensive review easily access accurate information. The medical chart can of an individual’s medical history and physical exami- also aid in clinical problem solving by tracking an individ- nations. ual’s baseline, or status on admission or entry into an of- • Orders. Contains medication and treatment orders by fice or health care system; orders and treatments provided the doctor, nurse practitioner, physician assistant, or in response to specific problems; and individual respons- other qualified health care team members. es. Another reason for the standard of clear documentation is the possibility that the record may be used in legal pro- • Medication record. Documents all medications admin- ceedings, when documentation serves as evidence in ex- istered. ploring and evaluating a person’s care experience. When • Treatment record. Documents all treatments received medical care is being referred to or questioned by the legal such as dressing changes or respiratory therapy. system, chart contents are frequently cited in court. For all • Procedures. Summarizes diagnostic or therapeutic pro- of these purposes, certain practices that protect the integri- cedures, i.e., colonoscopy or open-heart surgery. ty of the chart and provide essential information are rec- ommended for adding information and maintaining the • Tests. Provides reports and results of diagnostic evalua- chart. These practices include the following: tions, such as laboratory tests and electrocardiogra- phy tracings or radiography images or summaries of • Date and time should be included on all entries into the test results. record. 956 GALE ENCYCLOPEDIA OF SURGERY

• A person’s full name and other identifiers (i.e., medical record number, date of birth) should be included on all QUESTIONS records. TO ASK THE DOCTOR Medical charts • Continued records should be marked clearly (i.e., if a note is continued on the reverse side of a page). • In a particular setting, who has the authority to make entries in a medical chart? • Each page of documentation should be signed. • Who has access to the chart? • Blue or black non-erasable ink should be used on hand- • How is security maintained for medical written records. records? • Records should be maintained in chronological order. • Disposal or obliteration of any records or portions of records should be prevented. • The chart shouldn’t be left in an unprotected environ- • Documentation errors and corrections should be noted ment where unauthorized individuals may read or alter clearly, i.e., by drawing one line through the error and the contents. noting the presence of an error, and then initialing the Several methods of documentation have arisen in re- area. sponse to the need to accurately summarize a person’s • Excess empty space on the page should be avoided. A experience. In the critical care setting, flow records are line should be drawn through any unused space, the ini- often used to track frequent personal evaluations, checks tial, time, and date included. of equipment, and changes of equipment settings that are required. Flow records also offer the advantages of dis- • Only universally accepted abbreviations should be used. playing a large amount of information in a relatively • Unclear documentation such as illegible penmanship small space and allowing for quick comparisons. Flow should be avoided. records can also save time for a busy clinician by allow- ing for the completion of checklists versus requiring • Contradictory information should be avoided. For ex- written narrative notes. ample, if a nurse documents that a person has com- plained of abdominal pain throughout a shift, while a Narrative progress notes, while more time consum- physician documents that the person is free of pain, ing, are often the best way to capture specific informa- these discrepancies should be discussed and clarified. tion about an individual. Some institutions require only The resolution should be entered into the chart and charting by exception (CBE), which requires notes only signed by all parties involved in the disagreement. for significant or unusual findings. While this method may decrease repetition and lower required documenta- • Objective rather than subjective information should be tion time, most institutions that use CBE notes also re- included. For example, personality conflicts between quire a separate flow record that documents regular con- staff should not enter into the notes. All events involv- tact with a person. Many facilities or programs require ing an individual should be described as objectively as notes at regular intervals even when there is no signifi- possible, i.e., describe a hostile person by simply stat- cant occurrence, i.e., every nursing shift. Frequently ing the facts such as what the person said or did and used formats in individual notes include SOAP (subjec- surrounding circumstances or response of staff, without tive, objective, assessment, plan) notes. SOAP notes use using derogatory or judgmental language. an individual’s subjective statement to capture an im- • Any occurrence that might affect the person should be portant aspect of care, follow with a key objective state- documented. Documented information is considered ment regarding the person’s status, a description of the credible in court. Undocumented information is consid- clinical assessment, and a plan for how to address indi- ered questionable since there is no written record of its vidual problems or concerns. Focus charting and PIE occurrence. (problem-intervention-evaluation) charting use similar systems of notes that begin with a particular focus such • Current date and time should be used in documenta- as a nursing diagnosis or an individual concern. Nursing tion. For example, if a note is added after the fact, it diagnoses are often used as guides to nursing care by fo- should be labeled as an addendum and inserted in cor- cusing on individual care-recipient needs and responses rect chronological order, rather than trying to insert the to treatment. An example of a nursing diagnosis is fluid information on the date of the actual occurrence. volume for someone who is dehydrated. The notes • Actual statements of people should be recorded in would then focus on assessment for dehydration, inter- quotes. ventions to address the problem, and a plan for contin- GALE ENCYCLOPEDIA OF SURGERY 957

See also Health history; Physical examination; Talk- Medical charts ued care such as measurement of input and output and ing to the doctor. intravenous therapy. Resources Aftercare Current medical charts are maintained by members of the health care team and usually require clerical assis- BOOKS Carter, Jerome H. Electronic Medical Records: A Guide for tance such as a unit clerk in the hospital setting or Clinicians and Administrators. Philadelphia: American records clerk in a professional office. No alterations College of Physicians, 2001. should be made to the record unless they are required to Leiner, F., W. Gaus, R. Haux, and P. Knaup-Gregori. Medical clarify or correct information and are clearly marked as Data Management: A Practical Guide. New York: Springer-Verlag, 2003. such. After discharge, the medical records department of Skurka, Margaret A. Health Information Management: Princi- a facility checks for completeness and retains the record. ples and Organization for Health Record Services, 5th Similar checks may be made in professional office set- edition. San Francisc0: Jossey-Bass, 2003. tings. Sometimes, the record will be made available in Van De Velde, Rudi, Patrice Degoulet, and Daryl J. Daley. another format, i.e., recording paper charts on microfilm Clinical Information Systems: A Component-Based Ap- or computer imaging. Institutional policies and state proach. New York: Springer-Verlag, 2003. laws govern storage of charts on- and off-site and length PERIODICALS of storage time required. Gomez, E. “Health Insurance Portability and Accountability Act Protects Privacy of Medical Records.” Oncology Risks Nursing Society News, 18(1) 2003: 13. A major potential risk associated with medical O’Connor, P. J. “Electronic Medical Records and Diabetes charts is breach of confidentiality. This must be safe- Care Improvement: Are We Waiting for Godot?” Diabetes guarded at all times. Other risks include loss of materials Care, 26(3) 2003: 942–943. in a chart or incorrectly filing a chart so that subsequent Ross, S. E, and C. T. Lin. “The Effects of Promoting Patient retrieval is impeded or impossible. Access to Medical Records: A Review.” Journal of the American Medical Informatics Association, 10(2) 2003: Normal results 129–138. Vaszar, L. T, M. K. Cho, and T. A. Raffin. “Privacy Issues in All members of a health-care team require thorough Personalized Medicine.” Pharmacogenomics, 4(2) 2003: understanding of the medical chart and documentation 107–112. guidelines in order to provide competent care and main- Willison, D. J., K. Keshavjee, K. Nair, C. Goldsmith, and A. M. tain a clear, concise, and pertinent record. Health-care sys- Holbrook. “Patients’ Consent Preferences for Research tems often employ methods to guarantee thorough and Uses of Information in Electronic Medical Records: Inter- continuous use and review of charts across disciplines. For view and Survey Data.” British Medical Journal, 326(7385) 2003: 373–378. example, nursing staff may be required to sign below every new physician order to indicate that this information ORGANIZATIONS has been communicated, or internal quality assurance American Academy of Family Physicians. 11400 Tomahawk teams may study groups of charts to determine trends in Creek Parkway, Leawood, KS 66211-2672. (913) 906- missing or unclear documentation. In legal settings, health 6000. <[email protected]>. <http://www.aafp.org>. care team members may be called upon to interpret or ex- American Academy of Pediatrics. 141 Northwest Point Boule- plain chart notations as they relate to a specific legal case. vard, Elk Grove Village, IL 60007-1098. (847) 434-4000; Fax: (847) 434-8000. <[email protected]>. <http://www. Morbidity and mortality rates aap.org/default.htm>. American College of Physicians. 190 N Independence Mall Medical charts are made of paper or other materials. West, Philadelphia, PA 19106-1572. (800) 523-1546, They are subject to deterioration or loss. Transporting them x2600, or (215) 351-2600. <http://www.acponline.org>. may cause lifting injuries, but not lead to disease or death. American Hospital Association. One North Franklin, Chicago, IL 60606-3421. (312) 422-3000. <http://www.aha.org/ Alternatives index.asp>. American Medical Association. 515 N. State Street, Chicago, There are no alternatives for medical charts. Alter- IL 60610. (312) 464-5000. <http://www.ama-assn.org>. native mediums exist for paper records. These include American Medical Informatics Association. 4915 St. Elmo Av- fixing images on plastic media (photographs or x rays) enue, Suite 401, Bethesda, MD 20814. 301) 657-1291; or electronic storage. The latter can include magnetic Fax: (301) 657-1296. <http://www.amia.org/contact/f tape or computer disks. contact.html>. <http://www.amia.org>. 958 GALE ENCYCLOPEDIA OF SURGERY

sored research about the problem was undertaken by two KEY TERMS physicians, Lucian Leape and David Bates. In 1999, a re- port compiled by the Committee on Quality of Health Medical errors Consultation—Evaluation by an outside expert or Care in America and published by the Institute of Medi- specialist, someone other than the primary care cine (IOM) made headlines with its findings. As a result provider. of the IOM report, President Clinton asked the Quality Continuity—Consistency or coordination of de- Interagency Coordination Task Force (QuIC) to analyze tails. the problem of medical errors and patient safety, and make recommendations for improvement. The Report to Discipline—In health care, a specific area of preparation or training such as social work, nurs- the President on Medical Errors was published in Febru- ing, or nutrition. ary 2000. Documentation—The process of recording infor- It is important to understand the terms used by the mation in the medical chart, or the materials con- government and health-care professionals in describing tained in a medical chart. medical errors in order to distinguish between injury or death resulting from mistakes made by people on the one Interdisciplinary—Consisting of several interact- ing disciplines that work together to care for an in- hand, and unfortunate results of treatment on the other. dividual. Some allergic reactions to medications or failures to re- spond to cancer treatment, for example, result from Objective—Not biased by personal opinion; re- physical differences among patients or the known side peatable. effects of certain treatments, and not from prescribing Prognosis—Expected resolution or outcome of an the wrong drug or therapy for the patient’s condition. illness or injury. This type of negative outcome is called an adverse event Regulatory organization—Organization designed in official documents. Adverse events can be defined as to maintain or control quality in health care. undesirable and unintentional, though not necessarily unexpected, results of medical treatment. An example of Subjective—Influenced by personal opinion, bias, or experience; not reliably repeatable. an adverse event is discomfort in an artificial joint that continues after the expected recovery period, or a chron- ic headache following a spinal tap. A medical error, on the other hand, is an adverse OTHER event that could be prevented given the current state of Amyotrophic Lateral Sclerosis Disease Foundation [cited medical knowledge. The QuIC task force expanded the March 1, 2003]. <http://www.lougehrigsdisease.net/als_ IOM’s working definition of a medical error to cover as news/990106medical_charts.htm>. many types of errors as possible. Their definition of a Electronic Privacy Information Center [cited March 1, 2003]. medical error is as follows: “The failure of a planned ac- <http://www.epic.org/privacy/medical/>. tion to be completed as intended or the use of a wrong Peking University Health Sciences Center [cited March 1, plan to achieve an aim. Errors can include problems in 2003]. <http://mededucation.bjmu.edu.cn/chapter%20one/ practice, products, procedures, and systems.” A useful, major%20componentof%20medical%20charts.htm>. brief definition of a medical error is that it is a pre- Privacy Rights Clearinghouse [cited March 1, 2003]. <http:// ventable adverse event. www.privacyrights.org/fs/fs8-med.htm>. L. Fleming Fallon, Jr, MD, DrPH Statistics The statistics contained in the IOM report were star- tling. The authors of the report stated that between 45,000 and 98,000 Americans die each year as the result of medical errors. If the lower figure is used as an esti- Medical errors mate, deaths in hospitals resulting from medical errors are the eighth leading cause of mortality in the United States, surpassing deaths attributable to motor vehicle Introduction and definitions accidents (43,458), breast cancer (42,297), and AIDS The subject of medical errors is not a new one. (16,516). Moreover, these figures refer only to hospital- However, it did not come to widespread attention in the ized patients; they do not include people treated in out- United States until the 1990s, when government-spon- patient clinics, ambulatory surgery centers, doctors’ or GALE ENCYCLOPEDIA OF SURGERY 959

Medical errors dentists’ offices, college or military health services, or tion; the patient was given four times the correct daily dose, when the doctor intended the dosage to be admin- nursing homes. Medical errors certainly occur outside istered instead over a four-day period. Other cases in- hospitals; in 1999, the Massachusetts State Board of volve medication mix-ups due to drugs with very simi- Registration in Pharmacy estimated that 2.4 million pre- lar names. The Food and Drug Administration (FDA) scriptions are filled incorrectly each year in that state— has identified no fewer than 600 pairs of look-alike or which is only one of 50 states. sound-alike drug names since 1992. In terms of health-care costs, the IOM report esti- mated that medical errors cost the United States about • The increasing specialization and fragmentation of $37.6 billion each year; about half this sum pays for di- health care. The more people involved in a patient’s rect health care. treatment, the greater the possibility that important in- formation will be missing along the chain. The United States is not unique in having a high rate of medical errors. The United Kingdom, Australia, and • Human errors resulting from overwork and burnout. Sweden are presently undertaking studies of their re- For some years, hospital interns, residents, and nurses spective health care systems. British experts estimate have attributed many of the errors made in patient care that 40,000 patients die each year in the United Kingdom to the long hours they are expected to work, many as the result of medical errors. Australia has been testing times with inadequate sleep. With the coming of man- a new system for reporting errors since 1995. aged care, many hospitals have cut the size of their nursing staff and require those that remain to work mandatory overtime shifts. A study published in the Description Journal of the American Medical Association in Octo- There is no single universally accepted method of ber 2002 found a clear correlation between higher- classifying medical errors in order to describe them more than-average rates of patient mortality and higher-than- fully. The 2000 QuIC report lists five different classifica- average ratios of patients to nurses. tion schemes that have been used: • Manufacturing errors. Instances have been reported of • type of health care given (medication, surgery, diagnos- blood products being mislabeled during the production tic imaging, etc.) process, resulting in patients being given transfusions of an incompatible blood type. • severity of the injury (minor discomfort, serious injury, death, etc.) • Equipment failure. A typical example of equipment • legal definitions (negligence, malpractice, etc.) failure might be intravenous pump with a malfunction- ing valve, which would allow too much of the patient’s • setting (hospital, emergency room, intensive care unit, medication to be delivered over too short a time period. nursing home, etc.) • Diagnostic errors. A misdiagnosed illness can lead the • persons involved (physician, nurse, pharmacist, patient, doctor to prescribe an inappropriate type of treatment. etc.) Errors in interpreting diagnostic imaging have resulted The importance of these different ways to classify in surgeons operating on the wrong side of the patient’s medical errors is their indication that different types of body. Another common form of diagnostic error is fail- errors require different approaches to prevention and ure to act on abnormal test results. problem solving. For example, medication errors are • Poorly designed buildings and facilities. Hallways that often related to such communication problems as mis- end in sharp right angles, for example, increase the spelled words or illegible handwriting, whereas surgical likelihood of falls or collisions between people on foot errors are often related to unclear or misinterpreted diag- and patients being wheeled to an operating room. nostic images. Ways of thinking about medical errors Causes of medical errors One subject that has been emphasized in recent re- The causes of medical errors are complex and not ports on medical errors is the need to move away from a yet completely understood. Some causes that have been search for individual culprits to blame for medical errors. identified include the following: This judgmental approach has sometimes been called the • Communication errors. One widely publicized case “name, shame, and blame game.” It is characterized by from 1994 involved the death of a Boston newspaper the belief that medical errors result from inadequate columnist from an overdose of chemotherapy for breast training or from a few “bad apples” in the system. It is cancer due to misinterpretation of the doctor’s prescrip- then assumed that medical errors can be reduced or elim- 960 GALE ENCYCLOPEDIA OF SURGERY

inated by identifying the individuals, and firing or disci- • Make use of new technology to improve accuracy in plining them. The major drawback of this judgmental at- medication dosages and recording patients’ vital signs. titude is that it makes health care workers hesitate to re- Innovations in this field include giving nurses and resi- Medical errors port errors for fear of losing their own jobs or fear of dents handheld computers for recording patient data so some other form of reprisal. As a result of underreport- that they do not have to rely on human memory for so ing, hospital managers and others concerned with patient many details. Another innovation that helped Veterans safety often do not have an accurate picture of the fre- Administration (VA) hospitals cut the rate of medica- quency of occurrence of some types of medical errors. tion errors was the introduction of a handheld wireless bar-coding system. After the system went into opera- Both the IOM report and the QuIC report urge the tion at the end of 1998, the number of medication er- adoption of a model borrowed from industry that incor- rors in VA hospitals dropped by 70%. porates systems analysis. This model emphasizes mak- • Develop a nationwide database for error reporting and ing an entire system safer rather than punishing individu- analysis. At present, there is no unified system for track- als; it assumes that most errors result from problems ing different types of medical errors. An error in liver with procedures and work processes rather than bad or transplantation in August 2002 that cost the life of a incompetent people; and it analyzes all parts of the sys- baby led several researchers to recognize that there is tem in order to improve them. The industrial model is still no national registry recording transplant mismatch- sometimes referred to as the continuous quality improve- es. As a result, no one knows how many cases occur each ment model (CQI). Hospitals that are implementing year, let alone find ways to improve the present system. error-reduction programs based on the CQI model have found that a non-punitive procedure for reporting med- • Encourage patients to become more active participants ical errors has improved morale among the staff as well in their own health care. This recommendation includes as significantly reduced the number of medical errors. At asking more questions and requesting adequate expla- Columbia-Presbyterian Hospital, for example, patients nations from health care professionals, as well as re- as well as staff can report medical errors via the Internet, porting medical errors. a telephone hotline, or paper forms. • Address the fact that both patients and physicians have emotional as well as knowledge-related needs around the issue of medical errors. A report published in the Proposals for improvement Journal of the American Medical Association in Febru- Current proposals for reducing the rate of medical ary 2003 stated that patients clearly want emotional errors in the American health care system include the support from their doctors following an error, including following: an apology. The researchers also found, however, that doctors are as upset when an error occurs and, addition- • Adopt stricter standards of acceptable error rates. One ally, are unsure where to turn for emotional support. reason that industrial manufacturers have made great strides in product safety and error reduction is their What patients can do commitment to improving the quality of the work Patients are an important resource in lowering the rate process itself. of medical errors. The QuIC task force has put together • Standardize medical equipment and build in mechani- some fact sheets to help patients improve the safety of cal safeguards against human error. Anesthesiology is their health care. One of these fact sheets, entitled “Five the outstanding example of a medical specialty that has Steps to Safer Health Care,” gives the following tips: cut its error rate dramatically by asking medical equip- • Do not hesitate to ask questions of your health-care ment manufacturers to design ventilators with stan- provider, and ask him or her for explanations that you dardized controls and valves to prevent the oxygen con- can understand. tent from falling below that of room air. These changes • Keep lists of all medications, including over-the- were the result of studies that showed that many med- counter items as well as prescribed drugs. ical errors resulted from doctors having to use unfamil- iar ventilators and accidentally turning off the oxygen • Ask for the results of all tests and procedures, and find flow to the patient. out what the results mean for you. • Improve the working conditions for nurses and other • Find out what choices are available to you if your doc- hospital staff. Recommendations in this area include re- tor recommends hospital care. designing hospital facilities to improve efficiency and • If your doctor suggests surgery, ask for information minimize falls and other accidents, as well as reducing about the procedure itself, the reasons for it, and exact- the length of nursing shifts. ly what will happen during the operation. GALE ENCYCLOPEDIA OF SURGERY 961

This fact sheet, as well as a longer and more detailed Medicare patient fact sheet on medical errors, is available for free KEY TERMS download from the Agency for Health Research and Quality (AHRQ) Website or by telephone order from the result of a medical treatment or intervention. AHRQ Publications Clearinghouse at (800) 358-9295. Adverse event—An undesirable and unintended Medical error—A preventable adverse event. See also Managed care plans; Patient rights; Talking to the doctor. Systems analysis—An approach to medical errors and other management issues that looks for prob- lems in the work process rather than singling out Resources individuals as bad or incompetent. BOOKS Committee on Quality of Health Care in America, Institute of Medicine. To Err Is Human: Building a Safer Health Sys- tem. Washington, DC: National Academy Press, 2000. OTHER Agency for Healthcare Research and Quality (AHRQ) Fact PERIODICALS Sheet. Medical Errors: The Scope of the Problem. Publi- Aiken, Linda H., et al. “Hospital Nurse Staffing and Patient cation No. AHRQ 00-PO37. Mortality, Nurse Burnout, and Job Dissatisfaction.” Jour- Agency for Healthcare Research and Quality (AHRQ) Patient nal of the American Medical Association 288 (October Fact Sheet. 20 Tips to Help Prevent Medical Errors. Publi- 23-30, 2002): 1987–1993. cation No. AHRQ 00-PO38. Cottrill, Ken. “Mistaken Identity: Barcoding Recommended to Burton, Susan. “The Biggest Mistake of Their Lives.” New Combat Medical Errors.” Traffic World (July 2, 2001). York Times, March 16, 2003. <www.nytimes.com/2003/ Dougherty, Matthew. “Preventing Errors: New Initiative Aims 03/16/magazine/16MISTAKE.html>. to Catch Mistakes before They Happen.” In Vivo: News Quality Interagency Coordination Task Force (QuIC)) Patient from Columbia Health Sciences 1 (February 11, 2002). Fact Sheet. Five Steps to Safer Health Care, January 2001 Dovey, S. M., R. L. Phillips, L. A. Green, and G. E. Fryer. [cited March 17, 2003]. <www.ahrq.gov/consumer/5steps. “Types of Medical Errors Commonly Reported by Family htm>. Physicians.” American Family Physician 67 (February 15, Report of the Quality Interagency Coordination Task Force 2003): 697. (QuIC) to the President. Doing What Counts for Patient Friedman, Richard A. “Do Spelling and Penmanship Count? In Safety: Federal Actions to Reduce Medical Errors and Medicine, You Bet.” New York Times, March 11, 2003. Their Impact, 2000. Gallagher, T. H., et al. “Patients’ and Physicians’Attitudes Re- garding the Disclosure of Medical Errors.” Journal of the Rebecca Frey, PhD American Medical Association 289 (February 26, 2003): 1001–1007. Grady, Denise, and Lawrence K. Altman. “Suit Says Transplant Medical history see Health history Error Was Cause in Baby’s Death in August.” New York Times, March 12, 2003. Hsia, David C. “Medicare Quality Improvement: Bad Apples or Bad Systems?” Journal of the American Medical Asso- ciation 289 (January 15, 2003): 354–356. Nordenberg, Tamar. “Make No Mistake: Medical Errors Can Be Deadly Serious.” FDA Consumer Magazine (Septem- Medicare ber-October 2000). Definition Pyzdek, Thomas. “Motorola’s Six Sigma Program.” Quality Digest (December, 1997). Medicare is a national health insurance program cre- ated and administered by the federal government in the ORGANIZATIONS United States to address the medical needs of older Agency for Healthcare Research and Quality (AHRQ). 2101 American citizens. Medicare is available to U.S. citizens East Jefferson St., Suite 501, Rockville, MD 20852. (301) 65 years of age and older and some people with disabili- 594-1364. <www.ahcpr.gov>. ties under age 65. Institute of Medicine (IOM). The National Academies. 500 Fifth Street, NW, Washington, DC 20001. <www.iom. edu>. Description United States Food and Drug Administration (FDA). 5600 Fishers Lane, Rockville, MD 20857-0001. (888) 463- Medicare is the largest health insurance program in 6332. <www.fda.gov>. the United States. The program was created as part of the 962 GALE ENCYCLOPEDIA OF SURGERY

Social Security Act Amendment in 1965 and was put into government revenues generate the money used to sup- effect in 1966. At the end of 1966, Medicare served ap- port the Medicare program. Insurance coverage provided Medicare proximately 3.9 million individuals. As of 2003, it serves by Medicare is similar to that provided by private health about 41 million people. There are 5.6 million Medicare insurance carriers. Medicare usually pays 50–80% of the beneficiaries enrolled in managed care programs. medical bill, while the recipient pays the remaining bal- ance for services provided. In 1973, the Medicare program was expanded to in- clude people who have permanent kidney failure and need dialysis or transplants and people under the age of Normal results 65 who have specific types of disabilities. Medicare was As the population of the United States ages, con- originally administered by the Social Security Adminis- cerns about health care and the financing of quality tration, but in 1977, the program was transferred to the health care for all members of the elderly population Health Care Financing Administration (HCFA), which is grow. One concern is that health insurance provided by part of the United States Department of Health and the Medicare program will become obsolete or will be Human Services (DHHS). The Centers for Medicare and cut from the federal budget in an attempt to save money. Medicaid Services, an agency of the DHHS, is the ad- Another concern is that money provided by the Social ministrative agency. This agency also administers Med- Security Administration for Medicare will be depleted icaid programs. before the aging population of the United States can ac- Medicare is an entitlement program similar to Social tually benefit from the taxes they are now paying. A third Security and is not based on financial need. Medicare concern is coverage for prescription medications. benefits are available to all American citizens over the During the Clinton administration, several initiatives age of 65 because they or their spouses have paid Social were started that saved funds for Medicare. The DHHS Security taxes through their working years. Since also supports several initiatives to save and improve the Medicare is a federal program, the rules for eligibility re- program. However, continuance of the federal health in- main constant throughout the nation and coverage re- surance program is still a problem that American citizens mains constant regardless of where an individual re- expect legislators to resolve. ceives treatment in the United States. During the George W. Bush administration, there Medicare benefits are divided into two different cate- has been debate concerning coverage for prescription gories referred to as Part A and Part B. Medicare Part A is drugs. Health care reformers suggest that prescription hospital insurance that provides basic coverage for hospi- drugs be made available through the Medicare program tal stays and post-hospital nursing facilities, home health due to the high cost of such medications. This debate has care, and hospice care for terminally ill patients. Most not been resolved as of early 2003, and legislation has people automatically receive Part A when they turn 65 not been enacted. and do not have to pay a premium because they or their spouse paid Medicare taxes while they were working. Some of the successful initiatives undertaken since 1992 include: Medicare Part B is medical insurance. It covers most fees associated with basic doctor visits and laboratory test- • Fighting fraud and abuse. Much attention has focused ing. It also pays for some outpatient medical services such on Medicare abuse, fraud, and waste. As a result, over- as medical equipment, supplies, and home health care and payments were stopped, fraud was decreased, and physical therapy. However, these services and supplies are abuse was investigated. This has saved the Medicare only covered by Part B when medically necessary and program approximately $500 million per year. prescribed by a doctor. Enrollment in Part B is optional • Preserving the Medicare benefit. Due to aggressive ac- and the Medicare recipient pays a premium of approxi- tion by the federal government, it is estimated that mately $65 per month for these added benefits. The funds have been appropriated to keep Medicare viable amount of the premium is periodically adjusted. Not every through 2026. person who receives Medicare Part A enrolls in Part B. • Supporting Preventive Medicine and the Healthy Aging Although Medicare provides fairly broad coverage Project. Medicare programs are supporting preventive of medical treatment, neither Part A nor B pays for the medicine and diagnostic treatments in anticipation that cost of prescription drugs or other medications. preventive measures will improve the health of older Americans and thereby reduce health care costs. Medicare is funded solely by the federal govern- ment. States do not make matching contributions to the Medicare benefits and health care financing are Medicare fund. Social Security contributions, monthly major issues in the United States. Legislators and federal premiums paid by program participants, and general agencies continue to work on initiatives that will keep GALE ENCYCLOPEDIA OF SURGERY 963

Meningocele repair DHHS—The Department of Health and Human ORGANIZATIONS KEY TERMS American College of Physicians, 190 North Independence Mall West, Philadelphia, PA 19106-1572. (800) 523-1546 x2600 or (215) 351-2600. <http://www.acponline.org>. American College of Surgeons, 633 North St. Clair Street, Service. This federal agency houses the Centers for Chicago, IL 60611-32311. (312) 202-5000 fax: (312) 202- Medicare and Medicaid Services and distributes 5001. <http://www.facs.org>. funds for Medicaid. Entitlement—A program that creates a legal oblig- American Hospital Association, One North Franklin, Chicago, IL 60606-3421. (312) 422-3000 fax: (312) 422-4796. ation by the federal government to any person, <http://www.aha.org>. business, or government entity that meets the American Medical Association, 515 North State Street, Chica- legally defined criteria. Medicare is an entitlement go, IL 60610. (312) 464-5000. <http://www.ama-assn. for eligible individuals. org>. HCFA—Health Care Financing Administration. A Center for Medicare Advocacy, P.O. Box 350, Willimantic, CT federal agency that provides guidelines for the 06226. (860) 456-7790 or (202) 216-0028. <http://www. medicareadvocacy.org>. Medicaid program. OTHER Medicare Part A—Hospital insurance provided by Medicare, provided free to persons aged 65 and Centers for Medicare and Medicaid Services, U.S. Department older. of Health and Human Services. <http://cms.hhs.gov>. Medicare Information Center, <http://www.medicare.org>. Medicare Part B—Medical insurance provided by Medicare Rights Center, <http://www.medicarerights.org>. Medicare that requires recipients to pay a monthly United States Government Medicare Information, <http:// premium. Part B pays for some medical services www.medicare.gov>. Part A does not. L. Fleming Fallon, Jr., MD, DrPH health-care programs in place and working for the good of American citizens. See also Medicaid. Meningocele repair Resources Definition BOOKS A meningocele repair is a surgical procedure per- Blumenthal, David and Jon Erickson. Long-Term Care and Medicare Policy: Can We Improve the Continuity of Care? formed to repair an abnormal opening in the spinal col- Washington, DC: Brookings Institution Press, 2003. umn (called spina bifida) by draining excess fluid and Marmor, Theodore R. The Politics of Medicare. Second edi- closing the opening. tion. Hawthorne, NY: Aldine de Gruyter, 2000. Oberlander, Jonathan. Political Life of Medicare. Chicago: University of Chicago Press, 2003. Purpose Pratt, David A. and Sean K. Hornbeck. Social Security and The surgery is necessary to close this abnormal Medicare Answer Book. Gaithersburg, MD: Aspen, 2002. opening to decrease the risk of infection and protect the Stevens, Robert and Rosemary Stevens. Welfare Medicine in integrity of the spinal column and the tissue inside. America: A Case Study of Medicaid. Somerset, NJ: Trans- action Publishers, 2003. PERIODICALS Demographics Charatan, Fred. “Bush proposes Medicare reform.” British Med- According to the Spina Bifida Association of Ameri- ical Journal 326, no. 7389 (March 15, 2003): 570–572. ca, spina bifida is both the most common neural tube de- Hyman, David A. “Does Medicare care about quality? “ Per- fect and the most common birth defect resulting in per- spectives in Biology and Medicine 46, no. 1 (Winter 2003): 55–68. manent disability. It is estimated that about 40% of Amer- icans have spina bifida occulta. However, some people Pulec, Jack L. “Medicare: all or nothing.” Ear Nose and Throat who have it may have no symptoms and may therefore be Journal 82, no. 1 (January 2003): 7–8. Smith, John J., and Leonard Berlin. “Medicare fraud and unaware of their condition, so the percentage is an ap- abuse.” American Journal of Roentgenology 180, no. 3 proximation. Meningocele and myelomeningocele are (2003): 591–595. noticeable at birth and are paired together as spina bifida 964 GALE ENCYCLOPEDIA OF SURGERY

manifesta. Spina bifida manifesta occurs in about one in 1,000 births, with 4–5% being meningocele and 95–96% WHO PERFORMS being myelomeningocele. THE PROCEDURE AND WHERE IS IT PERFORMED? Meningocele repair Description Surgery on the spine is a very delicate proce- The term meningocele may be used to refer to more dure and needs to be done by a surgeon spe- than one condition. Spina bifida is a neural tube birth de- cializing in pediatric neurosurgery. It is best fect involving an abnormal opening in the spine. It oc- performed in a hospital with a pediatric inten- curs when the fetus’s spine does not close properly dur- sive care unit available to closely monitor the ing the first month of fetal development. In spina bifida infant after the surgery. occulta an opening in the spinal bones exists, but the neural tissue and membrane covering the spine (the meninges) are not exposed. Because there is no opening, the defect may appear as a dimple, or depression, at the the risks associated with increasing pressure on the brain. base of the spine (the sacrum). Another sign of spina bi- To prevent drying of the sac, it may be kept moist with fida occulta is the presence of tufts of hair at the sacrum. sterile dressings until surgery is begun. Once the anesthe- It is possible that while there is no opening, vertebrae are sia has put the baby to sleep and the surgery is pain-free, missing and there is damage to nerve tissue. a surgical incision is made into the sac. Excess fluid is drained, and the meninges is wrapped around the spine to A meningocele is a sac protruding from the spinal protect it. The opening is then closed with sutures. column, which contains some of the spinal fluid and meninges. The sac may be covered with skin or with the meninges, and does not contain neural tissue. It may be Diagnosis/Preparation located near the brain or along the spinal column. Hy- If an individual has spina bifida occulta, with no drocephalus is rarely present, and the neurological exam- outward signs of a neural tube defect and no symptoms, ination may be normal. Because the neural tissue re- the condition may go undetected. The protruding sacs as- mains intact, it can be repaired by the experienced neu- sociated with meningocele and myelomeningocele are rosurgeon, with excellent results. quite noticeable at birth. To understand the extent of the A myelomeningocele is the most severe type of defect x rays, ultrasound, computed tomography (CT) spina bifida because the spinal cord has herniated into scans, or magnetic resonance imaging (MRI) of the the protruding sac. Neural tissue and nerves may be ex- spine may be taken. posed. About 80% of myelomeningoceles occur at the Spina bifida may be diagnosed while the mother is lower back, where the lumbar and sacral regions join. still pregnant, through prenatal screening. If spina bifida Some people refer to myelomeningocele as spina bifida. is indicated, a blood test will show an elevated alpha fe- Because of the exposed neural tissue, significant symp- toprotein. However, elevated levels can be present with- toms may be present. These symptoms may include: out spina bifida, so further testing should be done if the • muscle weakness or paralysis in the hips and lower test is positive. There is an elevated alpha fetoprotein limbs level in about 85% of women with a fetus with spina bi- • no sensation in the part of the body below the defect fida. An ultrasound can reliable reveal the spinal struc- ture of the fetus. An amniocentesis may be done to • lack of bowel and bladder function check for chromosomal abnormalities. In amniocentesis, • fluid build-up in the brain, known as hydrocephalus a long syringe is used to draw amniotic fluid out from Because of the risk of neural tissue damage, the uterus through the mother’s abdomen. Because the swelling, and infection into the spinal fluid and brain protruding sac of the meningocele and myelomeningo- with an opening in the spinal column, surgery to repair cele can look the same on the outside, it is important to the meningocele or myelomeningocele is usually done have a clear diagnosis, as the anticipated outcome of the within 24 hours of birth. However, although the opening two conditions is very different. is closed, whatever damage has already been done to the neural tissue is permanent. If hydrocephalus is develop- Aftercare ing, the meningocele repair may be done first. Then, a few days later, a shunt can be inserted to resolve the hy- The infant will first spend some time in the recovery drocephalus. If the hydrocephalus is present at birth, the room, and then be transferred to an intensive care unit. two surgeries may be done at the same time to decrease The infant will be monitored for signs of excess bleeding GALE ENCYCLOPEDIA OF SURGERY 965

Meningocele repair • What is the extent of the neurological dam- Folic acid—A water-soluable vitamin belonging to KEY TERMS QUESTIONS TO ASK THE DOCTOR the B-complex group of vitamins. age? Meninges—The membrane covering neural tissue. • Is my child likely to walk? cess fluid. It is surgically implanted. The shunt • What experience do you have with this pro- Shunt—A shunt is a tube than is used to drain ex- cedure? drains the fluid from around the brain and sends it into the abdomen. • What complications have your patients expe- rienced with this procedure? • How long is my child likely to stay in the hospital? may be able to go to school, but will benefit from special education and associated services. There may be varying degrees of learning problems, and difficulties with the child’s attention span. An effective bowel and bladder- and infection. Temperature will be closely monitored. training program can help make attending school easier. Antibiotics will be given to decrease the risk of infection, Because of muscle weakness or paralysis, a child with and the infant will be positioned to lie flat on the stomach spina bifida will need physical therapy and may require to avoid pressure on the surgical wound. Extreme care is future surgeries. taken to keep the wound clean of urine and stool. Morbidity and mortality rates Risks With current medical and surgical treatments, about Surgical risks include infection and bleeding. Anes- 85% of infants survive, and about 50% will be able to thesia risks include a reaction to the medications used, walk. Bowel and bladder disorders contribute signifi- including difficulty breathing. During meningocele and cantly to morbidity and mortality in those with spina bi- myelomeningocele repair, there are additional risks of fida who survive past the age of two years. damage to the spinal column and infection of the spinal fluid surrounding the spine and brain. Damage to the neural tissue could result in paralysis, or loss of nerve Alternatives function (for example, loss of bowel and bladder con- There is no alternative to surgical repair. Risk of in- trol). There may also be an increased risk of an urinary fection and damage to the spine and brain is high with an tract infection. An infection of the meninges is called opening to the spine, so surgery is necessary to close the meningitis. However, further damage would be expected opening and drain the excess fluid that could put pres- if surgery were not done, and serious infection would be sure on the brain. The Spina Bifida Association of Amer- likely. As in all surgery, one must weigh the potential ica recommends that all women of childbearing age take risks against the expected benefits. 0.4 mg of folic acid daily, as this amount has been shown to decrease the likelihood of neural tube defects. Once a Normal results woman is aware of being pregnant, the critical first month of neural tube development has already past, and Results depend greatly on the extent of involvement folic acid cannot cure any damage that has been done. of exposed neural tissue and the condition of the infant prior to surgery. A meningocele repair can have excellent Resources results, as neural tissue does not extend into the protrud- ing sac. In myelomeningocele, the amount of exposed BOOKS neural tissue will determine the extent of lower limb Senisi, Ellen B. All Kinds of Friends, Even Green! Woodbine weakness, or paralysis. The infant will usually spend a House, November 2002. few weeks in the hospital after surgery before being able ORGANIZATIONS to be discharged home. As the child grows, it may be nec- March of Dimes Birth Defects Foundation. 1275 Mamaroneck essary to use braces, crutches, or a wheelchair for mobili- Avenue; White Plains, NY. Telephone (914) 428-7100. ty. If surgery for hydrocephalus is successful, the progno- <http://wwwmodimes.org>. sis is better. Children with a repaired myelomeningocele National Library of Medicine. <http://www.nlm.nih.gov>. 966 GALE ENCYCLOPEDIA OF SURGERY

Spina Bifida Association of America. 4590 MacArthur Boule- vard, NW, Suite 250; Washington, DC 20007-4226. Tele- WHO PERFORMS phone (800) 621-3141, (202)944-3285. [email protected]. THE PROCEDURE AND Mentoplasty <http://www.sbaa.org>. WHERE IS IT PERFORMED? Esther Csapo Rastegari, R.N., B.S.N., Ed.M. Mentoplasties may be performed by plastic sur- geons, oral surgeons, or maxillofacial surgeons. Fat injections and facial liposuction are usually performed by plastic surgeons. Chin implant insertions or direct reductions Mentoplasty are usually performed as outpatient procedures in the surgeon’s office or an ambulatory surgery Definition center. The patient may be given either general Mentoplasty is a term that refers to plastic surgery or local anesthesia. Sliding genioplasties can be procedures for the chin. It comes from the Latin word done as outpatient procedures; however, they mentum, which means chin, and the Greek verb plassein, are usually performed in hospitals under gener- which means “to form” or “to shape.” Mentoplasty is al anesthesia, particularly if the patient is having also known as genioplasty or chinplasty. orthognathic surgery at the same time. Purpose Demographics Mentoplasty may be done for several reasons: In spite of the fact that chin deformities are the most • To correct malformations of the chin resulting from de- common facial abnormality, mentoplasty is not one of velopmental abnormalities of the bones in the jaw. the more frequently performed procedures in plastic Sometimes the jawbones continue to grow on one side of surgery. In 2002, there were 18,352 mentoplasties per- the face but not the other, leading to facial asymmetry. In formed in the United States, compared to 117,831 face other instances a part of the jawbone is missing; this lifts and 282,876 liposuctions. Most mentoplasties are condition is known as congenital agenesis of the jaw. done in combination with rhinoplasties. • To reshape a chin that is out of proportion to other fa- Mentoplasty is primarily performed in adult pa- cial features. tients; it is not usually done in children until all perma- • As part of gender reassignment surgery. The size and nent teeth have come in and the jaw is close to its adult shape of the chin and lower jawline are somewhat dif- size. According to the American Society of Plastic Sur- ferent in men and women. Some people choose to have geons, 7% of patients who had mentoplasties in the Unit- mentoplasty as part of their gender transition. ed States in 2002 were 18 or younger; 35% were be- • As part of craniofacial reconstruction following trau- tween the ages of 19 and 34; 40% were between the ages ma or cancer surgery. of 35 and 50, while another 15% were between 51 and 64. Only 3% were over 65. • As part of orthognathic surgery. Orthognathic surgery involves repositioning the facial bones in order to cor- With respect to sex, women account for 69% of rect deformities that affect the patient’s ability to speak mentoplasty patients; only 31% are men. or chew normally. Insurance coverage for mentoplasty depends on its Description purpose. Chin reshaping that is done to improve personal Mentoplasties fall into two large categories: proce- appearance is not usually covered by insurance. Mento- dures that augment (increase) small or receding chins; plasty that is performed as a reconstructive procedure and those that reduce large or protruding chins. Chin after trauma, genetic deformity, or orthognathic surgery augmentation is done more frequently than chin reduc- may be covered by insurance. tion, reflecting the fact that microgenia (small chin) is The cost of mentoplasty varies considerably accord- the most common abnormality of the chin. ing to the complexity of the procedure. The average sur- Chin augmentation geon’s fee for a chin implant was $1,612 in 2002. The average fee for a sliding genioplasty, however, was Chin augmentation can be performed by inserting an $4,000–$6,000. implant under the skin of the chin or by performing a GALE ENCYCLOPEDIA OF SURGERY 967

Mentoplasty TO ASK THE DOCTOR Diagnosis/Preparation QUESTIONS Diagnosis Diagnostic evaluation consists of a facial analysis as • Would you recommend a chin implant or a is one of the three most significant parts of the face from sliding genioplasty in my case? well as a complete dental and medical history. The chin an aesthetic standpoint, the others being the forehead • Would you use a submental or an intraoral and the nose. Many patients who are concerned about approach to a chin augmentation? the size of their nose, for example, can be helped by hav- • How many mentoplasties have you performed? ing a too-small chin augmented as well as having the • Should I consider a mentoplasty in combina- nose reshaped. In the facial analysis, the face is divided tion with another facial procedure? into thirds, with the mouth and chin in the lowest third. The surgeon compares the proportions of the features in each third in order to determine the most suitable proce- dure for restoring balance. The patient will be pho- sliding genioplasty. Insertion of an implant takes 30–60 tographed from several angles to document the condition minutes, while a sliding genioplasty takes slightly of the chin before surgery. longer, 45–90 minutes. If the mentoplasty is done togeth- er with orthognathic surgery, the operation may take as The dental history and x ray studies of the head and long as three hours. jaw are necessary in order to determine whether the fa- cial disproportion can be corrected by an implant or sim- Chin implants are used in patients with mild or ple reduction, or whether orthognathic surgery is re- moderate microgenia. At one time they were made of quired. Patients who have severe malocclusion (irregular cartilage taken from donors or from other sites on the pa- contact between the teeth in the upper and lower jaws) or tient’s body, but as of 2003 alloplastic implants (made deformities of the facial bones are usually referred to a from inert foreign materials) are used more often be- maxillofacial specialist for reconstructive surgery. cause they reduce the risk of infection. To insert the im- plant, the surgeon can choose to make the incision under Lastly, the surgeon will evaluate the patient for any the chin (submental) or inside the mouth (intraoral). In signs of psychological instability, including unrealistic either case, the surgeon cuts through several layers of tis- expectations of the results of surgery. sue, taking care to avoid damaging the major nerve in the chin. The surgeon makes a pocket in the connective tis- Preparation sue inside the chin and washes it out with an antiseptic Patients should stop smoking and discontinue all solution. The sterile implant is then inserted in the pock- medications containing aspirin or NSAIDs for two et and positioned properly. The incision is closed and the weeks prior to mentoplasty. If the surgeon is planning to wound covered with Steri-Strips. make a submental incision, the patient should use an an- A sliding genioplasty may be performed if the pa- tibacterial facial cleanser for two days before surgery. tient’s chin is too small for augmentation with an im- Patients scheduled for an intraoral approach should rinse plant, or if the deformity is more complex. In this proce- the mouth with mouthwash three times a day for two dure, the surgeon cuts through the jawbone with an oscil- days before surgery. They should not eat or drink any- lating saw and removes part of the bone. He or she then thing for eight hours prior to the procedure. moves the bone segment forward, holding it in place with metal plates and screws. After the bone segment has Aftercare been fixed in place, the incision is closed and the pa- Patients should have someone drive them home after tient’s head is wrapped with a pressure dressing. the procedure. They are given medication for discomfort and a one-week course of antibiotic medication to reduce Chin reduction the risk of infection. Most patients can return to work in seven to 10 days. Reduction of an overly large or protruding chin may be done either by direct reduction or a sliding genioplasty. Other aspects of aftercare include the following: In a direct reduction, the surgeon makes either a submen- • a soft or liquid diet for four to five days tal or an intraoral incision and removes excess bone from • raising the head of the bed or using two to three pillows the chin with a burr. A sliding genioplasty reduction is similar to a genioplasty to augment the chin, except that • rinsing the mouth with a solution of hydrogen peroxide the bone segment is moved backward rather than forward. and warm water two to three times daily 968 GALE ENCYCLOPEDIA OF SURGERY

• avoiding sleeping on the face and unnecessary touching Liposuction of the chin area Facial liposuction can be used together with or in- • avoiding vigorous physical exercise for about two stead of mentoplasty to improve the patient’s profile. In Mentoplasty weeks particular, removal of fatty tissue below the chin can make a receding chin look larger or more prominent. Risks See also Face lift; Rhinoplasty. In addition to infection, bleeding, and an allergic re- Resources action to the anesthetic, the risks of insertion of a chin BOOKS implant include: Sargent, Larry, MD. The Craniofacial Surgery Book. Chat- • deformity of the chin following an infection tanooga, TN: Erlanger Health System, 2000. “Temporomandibular Disorders.” In The Merck Manual of Di- • injury to the major nerve in the chin, leading to loss of agnosis and Therapy, edited by Mark H. Beers, MD, and feeling or paralysis of the chin muscles Robert Berkow, MD. Whitehouse Station, NJ: Merck Re- • erosion of the bone beneath the implant search Laboratories, 1999. PERIODICALS • moving around or dislocation of the implant Abraham, Manoj T., MD, and Thomas Romo III, MD. “Lipo- • extrusion (pushing out) of the implant suction of the Face and Neck.” eMedicine. January 8, Specific risks associated with sliding genioplasties 2003 [cited April 22, 2003]. <http://www.emedicine. com/ent/topic581.htm>. include: Chang, Edward, MD, DDS, Samuel M. Lam, MD, and Edward • under- or over-correction of the defect Farrior, MD. “Genioplasty.” eMedicine. June 7, 2002 [cited April 20, 2003]. <http://www.emedicine.com/ent/ • injury to the major nerve in the chin topic106.htm>. • failure of the bone segment to reunite properly with the Chang, E. W., S. M. Lam, M. Karen, and J. L. Donlevy. “Sliding other parts of the jaw Genioplasty for Correction of Chin Abnormalities.” Archives of Facial Plastic Surgery 3 (January-March 2001): 8–15. • damage to the roots of the teeth Danahey, D. G., S. H. Dayan, A. G. Benson, and J. A. Ness. • hematoma (a collection of blood within a body organ “Importance of Chin Evaluation and Treatment to Opti- or tissue caused by leakage from broken blood vessels; mizing Neck Rejuvenation Surgery.” Facial Plastic it can damage the results of a mentoplasty by causing Surgery 17 (May 2001): 91–97. pressure that distorts the final shape of the chin) Galli, Suzanne K. D., MD, and Philip J. Miller, MD. “Chin Im- plants.” eMedicine. May 15, 2002 [cited April 22, 2003]. <http://www.emedicine.com/ent/topic628.htm>. Normal results Grossman, John A., MD. “Facial Alloplastic Implants, Chin.” eMedicine. July 5, 2001 [cited April 21, 2003]. <http:// Normal results of either augmentation or reduction www.emedicine.com/plastic/topic56.htm>. mentoplasty include correction of facial asymmetry and Jafar, M., and R. A. Younger. “Screw Fixation Mentoplasty.” disproportion. The functioning of the jaw is also often Journal of Otolaryngology 29 (October 2000): 274–278. improved. Patients who have had a mentoplasty are usu- Meszaros, Liz. “Sliding Genioplasty Successful in Correcting ally very satisfied with the results. Chin Abnormalities.” Cosmetic Surgery Times, September 1, 2001. Morbidity and mortality rates Patel, Pravin K., MD, Hongshik Han, MD, and Nak-Heon Kang, MD. “Craniofacial, Orthognathic Surgery.” eMedi- The rate of complications with chin implants as well cine. December 27, 2001 [cited April 21, 2003]. <http:// as sliding genioplasties is about 5%. www.emedicine.com/plastic/topic177.htm>. Siwolop, Sana. “Beyond Botox: An Industry’s Quest for Smooth Skin.” New York Times, March 9, 2003 [cited Alternatives March 9, 2003]. <http://www.nytimes.com/2003/03/09/ Fat injections business/09FACE.html>. ORGANIZATIONS In some cases, fat may be injected into the area American Academy of Facial Plastic and Reconstructive below the chin to plump up the skin and minimize the Surgery (AAFPRS). 310 South Henry Street, Alexandria, apparent size of the chin. This technique, however, is VA 22314. (703) 299-9291. <http://www.facemd.org>. limited to minor disproportions of chin size. In addition, American Society of Plastic Surgeons (ASPS). 444 East Algo- fat injections must be repeated periodically as the fat is nquin Road, Arlington Heights, IL 60005. (847) 228- gradually absorbed by the body. 9900. <http://www.plasticsurgery.org>. GALE ENCYCLOPEDIA OF SURGERY 969

Microsurgery Aesthetic—Pertaining to beauty. Plastic surgery Microalbumin test see Urinalysis KEY TERMS done to improve the patient’s appearance is some- times called aesthetic surgery. Agenesis—The absence of an organ or body part Microsurgery due to developmental failure. Definition Alloplast—An implant made of an inert foreign material such as silicone or hydroxyapatite. Microsurgery is surgery that is performed on very small structures, such as blood vessels and nerves, with Congenital—Present at the time of birth. specialized instruments under a microscope. Extrusion—Pushing out or expulsion. Extrusion of a chin implant is one possible complication of mentoplasty. Purpose Genioplasty—Another word for mentoplasty. It Microsurgical procedures are performed on parts of comes from the Greek word for “chin.” the body that are best visualized under a microscope. Ex- Hematoma—A localized collection of blood in an amples of such structures are small blood vessels, organ or tissue due to broken blood vessels. nerves, and tubes. Microsurgery uses techniques that Intraoral—Inside the mouth. have been performed by surgeons since the early twenti- Malocclusion—Malpositioning and defective con- eth century, such as blood vessel repair and organ trans- tact between opposing teeth in the upper and plantation, but under conditions that make traditional lower jaws. vascular surgery difficult or impossible. Microgenia—An extremely small chin. It is the The first microvascular surgery, using a microscope most common deformity of the chin. to aid in the repair of blood vessels, was described by Orthognathic surgery—Surgery that corrects de- Jules Jacobson of the University of Vermont in 1960. formities or malpositioning of the bones in the The first successful replantation (reattachment of an am- jaw. The term comes from two Greek words mean- putated body part) was reported in 1964 by Harry ing straight and jaw. Bunke. This replantation of a rabbit’s ear was significant because blood vessels smaller than 0.04 in (0.1 cm)— Sliding genioplasty—A complex plastic surgery procedure in which the patient’s jawbone is cut, similar in size to the blood vessels found in a human moved forward or backward, and repositioned hand—were successfully attached. Two years later, the with metal plates and screws. successful replantation of a toe to the hand of a monkey was made possible using microsurgical techniques. Soon Submental—Underneath the chin. thereafter, microsurgery began being used in a number of clinical settings. Numerous surgical specialties utilize the techniques FACES: The National Craniofacial Association. P. O. Box of microsurgery. Otolaryngologists (ear, nose, and 11082, Chattanooga, TN 37401. (800) 332-2373. <http:// throat doctors) perform microsurgery on the small, deli- www.faces-cranio.org>. cate structures of the inner ear or the vocal cords. OTHER Cataracts are removed by ophthalmologists (eye doc- tors), who also perform corneal transplants and treat eye American Academy of Facial Plastic and Reconstructive Surgery. 2001 Membership Survey: Trends in Facial Plas- conditions like glaucoma. Urologists can reverse vasec- tic Surgery. Alexandria, VA: AAFPRS, 2002. tomies (male sterilization), and gynecologists can re- American Academy of Facial Plastic and Reconstructive verse tubal ligations (female sterilization), giving peo- Surgery. Procedures: Understanding Mentoplasty Surgery. ple new choices about having children. Microsurgical [cited April 20, 2003]. <http://www.facial-plastic-surgery. techniques are used by plastic surgeons to reconstruct org/patient/procedures/mentoplasty.html>. damaged or disfigured skin, muscles, or other tissues, or American Society of Plastic Surgeons. Procedures: Facial Im- to transplant tissues from other parts of the body. And, plants. [cited April 20, 2003]. <http://www.plasticsurgery. importantly, a number of specialties can collaborate to org/public_education/procedures/FacialImplants.cfm>. treat patients who have limbs or other body parts; under certain circumstances, amputated parts can be reat- Rebecca Frey, Ph.D. tached, or another body part can be replanted in the 970 GALE ENCYCLOPEDIA OF SURGERY

Surgeon performing microsurgery using specialized instruments and a microscope. (Custom Medical Stock Photo. Repro- Microsurgery duced by permission.) place of one lost (for example, a great toe replacing a a low level of light in the rest of the operating room. lost or damaged thumb). Two or more sets of lenses allow a surgeon and an assis- tant to view the operating field and focus and zoom inde- Today, microsurgery can be lifesaving. Neurosur- pendently. A video camera allows the rest of the surgical geons can treat vascular abnormalities found in the brain, team to view the operating field on a display screen. Fea- and cancerous tumors can be removed. tures that come on some microscopes include foot and/or mouth switch controls and motorized zoom and focus. Description A magnification of five to forty times (5–40x) is Equipment generally required for microsurgery. A lower magnifica- tion may be used to identify and expose structures, while Microsurgical equipment magnifies the operating a higher magnification is most often used for microsurgi- field, provide instrumentation precise enough to maneu- cal repair. Alternatively, surgical loupes (magnifying ver under high magnification, and allow the surgeon to lenses mounted on a pair of eyeglasses) may be used for operate on structures barely visible to the human eye. lower magnifications (2–6x). The most important tools used by the microsurgeon are the microscope, microsurgical instruments, and microsu- INSTRUMENTS. Microsurgical instruments differ ture materials. from conventional instruments in a number of ways. They must be capable of delicately manipulating struc- MICROSCOPE. While operating microscopes may tures barely visible to the naked eye, but with handles differ according to their specific use, certain features are large enough to hold comfortably and securely. They standard. The microscope may be floor- or ceiling- must also take into account the tremor of the surgeon’s mounted, with a moveable arm that allows the surgeon to hand, greatly amplified under magnification. manipulate the microscope’s position. A view of the sur- gical site is afforded by a set of lenses and a high-intensi- Some of the various instruments that are used in mi- ty light source. This lighting is enhanced by maintaining crosurgery include: GALE ENCYCLOPEDIA OF SURGERY 971

Microsurgery • forceps gical techniques. For this reason, a microsurgical labo- ratory is made available to surgeons for training and • needle holders (for suturing) practice. • scissors • vascular clamps (for controlling bleeding) and clamp applicators Techniques Most microsurgical procedures utilize a set of basic • irrigators (for washing structures in the surgical field) techniques that must be mastered by the surgeon. These include blood vessel repair, vein grafting, and nerve re- • vessel dilators (for opening up the cut end of a blood pair and grafting. vessel) BLOOD VESSEL REPAIR. Blood vessel, or vascular • various standard surgical tools anastomosis, is the connection of two cut or separate SUTURE MATERIALS. Suturing, or stitching, is done blood vessels to form a continuous channel. Anasto- by means of specialized thread and needles. The diame- moses may be end-to-end (between two cut ends of a ter (gauge) of suture thread ranges in size and depends blood vessel) or end-to-side (a connection of one cut end on the procedure and tissue to be sutured. Conventional of a blood vessel to the wall of another vessel). suturing usually requires gauges of 2-0 (0.3 mm) to 6-0 The first step of creating an anastomosis is to iden- (0.07 mm). Conversely, gauges of 9-0 (0.03 mm) to 12-0 tify and expose the blood vessel by isolating it from (0.001 mm) are generally used for microsurgery. Suture surrounding tissues. Each end of the vessel is irrigated thread may be absorbable (able to be broken down in the (washed) and secured with clamps for the duration of body after a definite amount of time) or non-absorbable the procedure. A piece of contrast material is placed be- (retaining its strength indefinitely), natural (made of silk, hind the surgical site so that the tiny vessel can be more gut, linen, or other natural material) or synthetic (made easily visualized. The magnification is then increased of nylon, polyester, wire, or other man-made material). for the next segment of surgery. The first suture is The type of suture thread used depends on the procedure placed through the full thickness of the vessel wall; the and tissue to be sutured. second and third sutures are then placed at 120° from The suture needle comes in various sizes (diameters the first. Subsequent sutures are placed evenly in the re- and length) and shapes (straight or curved), and also maining spaces. Arteries 1 millimeter in diameter gen- with different point types (rounded, cutting, or blunt). It erally require between five and eight stitches around comes with suture thread preattached to one end; this is the perimeter, and veins of the same size between seven called the swage. As in the case of suture thread, the type and 10. Once the last suture has been placed, the of needle used depends on the procedure and tissue to be clamps are released and blood is allowed to flow sutured; generally, needles with a diameter of less than through the anastomosis. If excessive bleeding occurs 0.15 mm are used for microsurgery. between the stitches, the vessel is reclamped and addi- tional sutures are placed. Training The procedure for an end-to-side anastomosis is For a surgeon to perform microsurgery in a clinical similar, except that an oval-shaped hole is cut in the setting, extensive training and practice are required. A wall of the recipient vessel. Sutures are first placed at basic knowledge of anatomy and surgical techniques is each of the oval to connect the attaching vessel to the re- essential. After a thorough introduction to the operating cipient vessel, and then placed evenly to fill in the re- microscope and other microsurgical equipment, basic maining spaces. techniques are introduced using small animals as the ex- VEIN GRAFTING. Vein grafting is an alternative pro- perimental model. Specifically, surgeons must be taught cedure to end-to-end anastomosis and may be pursued if how to maintain correct posture and to maintain constant cut ends of a blood vessel cannot be attached without visual contact with the microscope during surgery, how tension. Nonessential veins similar in diameter to the re- to properly hold and use the instruments, how to mini- cipient blood vessel can be removed from the hand, arm, mize the amount of hand tremor, and how to perform or foot. If the graft is to be used to reconstruct an artery, basic techniques, such as suturing. After becoming profi- its direction is reversed so that the venous valves do not cient at these skills, more advanced techniques can be interfere with blood flow. End-to-end anastomosis is taught, including procedures regarding how to treat spe- then performed on each end of the graft, using the suture cific conditions. techniques described above. Extensive and ongoing practice is necessary for a NERVE REPAIR. The process of connecting two cut surgeon to maintain adequate proficiency at microsur- ends of a nerve is called neurorrhaphy, or nerve anasto- 972 GALE ENCYCLOPEDIA OF SURGERY

mosis. Peripheral nerves are composed of bunches of taken on a regular basis, including nonsteroidal anti-in- nerve fibers called fascicles that are enclosed by a layer flammatory drugs (NSAIDs), such as aspirin. Patients called the perineurium; the epineurium is the outer layer taking blood thinners, such as Coumadin or Heparin Microsurgery of the nerve that encases the fascicles. Nerve repair may (generic name: warfarin), should not adjust their medica- involve suturing of the epineurium only, the perineurium tion themselves, but should speak with their prescribing only, or through both layers. doctors regarding their upcoming surgery). Patients should never adjust dosage without their doctors’ ap- Many of the techniques used for blood vessel anas- proval. This is especially important for elderly patients, tomoses are also used for nerves. The cut ends of the asthmatics, those with hypertension, or those who are on nerve are exposed, then isolated from surrounding tis- ACE inhibitors. sues. The ends are trimmed so that healthy nerve tissue is exposed, and a piece of contrast material placed be- The patient will be placed under general anesthesia hind the nerve for better visualization. Each nerve end for the duration of the procedure. The advantages to gen- is examined to determine the pattern of fascicles; the eral anesthesia are that the patient remains unconscious nerve ends are then rotated so that the fascicle patterns and completely relaxed during the procedure, imperative align. Sutures may be placed around the circumference because of the precise nature and extended duration of of the epineurium; this is called epineurial neurorrha- the surgery. The patient must be able to tolerate the long phy. The perineurium of each cut fascicle end may be surgery and therefore must be relatively stable condition; stitched with excess epineurium removed (perineurial complex surgeries may take up to 12 hours or more. neurorrhaphy), or both layers may be sutured (epiper- Microsurgery makes possible a number of recon- ineurial neurorrhaphy). structive procedures that would be more difficult or im- NERVE GRAFTING. If there is a large gap between possible with conventional surgery. Some of the more the cut ends of a nerve, neurorrhaphy cannot be per- frequently performed microsurgical procedures include: formed without creating tension in the nerve that can in- • Replantation. This emergency surgery is performed to terfere with postsurgical function. A piece of nerve from reattach an amputated body part such as a finger, arm, another part of body may be used to create a nerve graft or foot. Replantation surgery requires a series of time- that is stitched into place using anastomosis techniques. and energy-intensive steps to reattach all of the struc- A disadvantage to nerve grafting is that a loss of function tures while the amputated part is still viable. The cut or sensation is experienced from the donor nerve site. A bone must be shortened slightly so that blood vessels common nerve used for grafting is the sural nerve, which and nerves can be reattached without tension. Anasto- innervates parts of the lower leg. moses are created between cut arteries and veins and blood flow is reestablished to the amputated part. Ten- Diagnosis/Preparation dons (if present) are then repaired, followed by nerves and soft tissues. Further procedures may be necessary In an emergency situation, such as an amputation to completely the reconstruction depending on the ex- or crushing injury, a number of steps must be taken im- tent of the injury. mediately to improve the odds that replantation or recon- struction will be successful. An IV line is placed so that • Transplantation. In some cases an amputated part can- fluids and antibiotics can be administered. The injured not be reattached, or tissue is deformed because of a area is x rayed so that the extent of the injury can be de- congenital defect or an injury. Transplantation may termined, and the amputated body part is wrapped in then be an option. The great toe or second toe may be sterile gauze and placed on ice, so that the tissues are removed from a patient’s foot and transplanted to the preserved. To prevent freezing, the body part must not be hand to replace a missing finger. A segment of rib packed below the ice. The patient is transported by am- along with its blood supply can be used to reconstruct bulance or helicopter to the nearest surgical center capa- bones in the face and jaw. ble of microsurgical repair. • Free-tissue transfers. Also called free flaps, free-tissue In other cases, a patient may suffer from a chronic transfers may be used to reconstruct damaged tissues condition or wound, and microsurgery can be scheduled that cannot be treated with skin grafts, closed by tradi- as an elective procedure. Prior to surgery, the patient will tional methods such as suturing, or allowed to heal be instructed to refrain from tobacco use because it inter- without intervention. This includes tissues that have feres with healing. In addition, the patient will be told constricted after a burn, injuries in which there is not not to eat after midnight the day of surgery. It is impor- sufficient skin to properly close the wound, or tissues tant that the patient inform the doctor completely about that have been removed as a result of treatment for can- any prior surgeries, medical conditions, or medications cer. Examples of tissues that may be transferred with GALE ENCYCLOPEDIA OF SURGERY 973

Minimally invasive heart surgery Capillaries—Tiny blood vessels that deliver oxy- fects circulation. Bed rest may be prescribed for a period KEY TERMS of days to weeks after surgery, depending on the proce- dure. Patients who have had a hand, finger, or multiple fingers replanted must keep the part elevated at heart gen to tissues. level to help blood flow and decrease swelling. Peripheral nerves—The nerves outside of the Some form of rehabilitation is often recommended brain and spinal cord. after microsurgery. This includes a program of individu- Vascular surgery—A branch of medicine that alized exercises used to restore function to a replanted or transplanted body part. In some cases where problems deals with the surgical repair of disorders of or in- juries to the blood vessels. be recommended. Leeches are worms that attach to the Venous valves—Folds on the inner lining of the skin and draw blood while also injecting substances into veins that prevent the backflow of blood. with circulation occur after surgery, leech therapy may the skin that act as a local anesthetic and an anticoagu- lant (preventing the formation of blood clots). Therapy involves attaching a leech to the replanted part or tissue microsurgical techniques are skin, muscle, fat, bone, flap and allow it to feed for 15 to 30 minutes, several and intestine. times a day, until blood flow is established. Resources Aftercare BOOKS Following surgery, the patient is given intravenous Jobe, Mark T. “Microsurgery” (Chapter 60). In Campbell’s Op- fluids and usually progresses to a liquid diet within 12 to erative Orthopedics, 10th ed. Philadelphia: Mosby, Inc., 24 hours, and a regular diet soon thereafter. The patient 2003. must be kept warm and adequately hydrated, and the sur- ORGANIZATIONS gical site is elevated if possible to help drain excess flu- American Society for Reconstructive Microsurgery. 20 North ids. Medications are administered to help manage pain. Michigan Ave., Suite 700, Chicago, IL 60602. (312) 456- The color, temperature, quality of capillary refill, and tis- 9579. <http://www.microsurg.org>. sue turgor (fullness) of the surgical site are closely moni- tored. Skin should be pink, warm, and have one- to two- OTHER second capillary refill. Conversely, tissue that is pale or Buncke, Harry J. Microsurgery: Transplantation-Replantation. blue, cool, with no refill or rapid refill may indicate a 2002 [cited April 25, 2003]. <http://buncke.org/book/ problem with blood flow. contents.html>. Chang, James. “Principles of Microsurgery.” eMedicine. Au- Certain tests may be recommended to further evalu- gust 5, 2002 [cited April 25, 2003]. <http://www.e ate the surgical site. These include: medicine.com/plastic/topic262.htm>. “Microsurgery.” California Pacific Medical Center. [cited April • Doppler ultrasound. This technology uses high-fre- 25, 2003]. <http://www.cpmc.org/advanced/microsurg/>. quency sound waves to evaluate the flow of blood to “Online Atlas of Microsurgery.” Microsurgeon.org. March 20, and from the surgical site. 2003 [cited April 25, 2003]. <http://www.microsurgeon. • Intravenous fluorescein. After a chemical dye called org>. fluorescein is administered to the patient, a specialized machine called a fluorimeter is used to determine how Stephanie Dionne Sherk much blood is flowing through the surgical site. • Pulse oximetry. A pulse oximeter measures the amount of oxygen in the blood and tracks the patient’s pulse. • Arteriography. X rays are taken of the surgical site after a contrast dye has been injected into the bloodstream to Minimally invasive determine the condition of vascular anastomoses. heart surgery When the patient is discharged from the hospital, he Definition or she will receive instructions for aftercare. Exposure to tobacco must be limited for at least six weeks following Minimally invasive heart surgery refers to surgery the surgery, as nicotine interferes with circulation. The performed on the beating heart to provide coronary patient must remain warm as body temperature also af- artery bypass grafting. This technique is often referred to 974 GALE ENCYCLOPEDIA OF SURGERY

as MIDCAB, minimally invasive direct coronary artery bypass; or OPCAB, off-pump CABG. Minimally invasive heart surgery Purpose Minimally invasive heart surgery is performed on the diseased heart to reroute blood around clogged arter- Minimally invasive heart surgery ies and improve the blood and oxygen supply to the heart. This approach provides patients some benefit in that cardiopulmonary bypass (use of a heart-lung ma- chine) may be avoided, and smaller incisions can be used instead of the standard sternotomy (incision through the sternum, or breast bone) approach. Faster recovery time, Tubes to Heart decreased procedure costs, and reduced morbidity and heart-lung mortality are the goals of this technique. machine Minimally invasive technique is not new to the field of cardiac surgery. It was performed as early as the 1950s, although the technology associated with stabiliz- ing the cardiac structure during the procedure has be- A. come more sophisticated. Also, the anesthesiologist and perfusionist (person monitoring blood flow) have devel- oped better techniques to preserve cardiac function dur- ing the procedure to help the surgeon achieve the desired outcome. During the 1990s these new techniques were named: off-pump CABG (OPCAB) and minimally inva- sive direct coronary artery bypass (MIDCAB). The Incision MIDCAB procedure includes procedures done both with between ribs and without cardiopulmonary bypass, the later being re- ferred to as off-pump MIDCAB. Unless otherwise speci- fied, MIDCAB refers to both types of procedures. Minimally invasive valve surgery has been an out- growth of the success with minimally invasive coronary artery bypass grafting. Incisions other then the tradition- al sternotomy allow access to the heart. Minimally inva- sive valve surgery still requires cardiopulmonary by- pass, since this is a true open-heart procedure, (i.e. this is not surgery that is done while the heart is beating). B. New tools in managing cardioplegic cardiac arrest allow for the smaller incision unobstructed by the required in- strumentation. Cannulation of the femoral vessels in- Catheter in femoral artery stead of the larger vessels of the heart also improves vi- sualization. In traditional open heart surgery, a large incision is made in Demographics the chest, and the sternum must be broken (A). Minimally Patients under the age of 70, but not limited by age, invasive surgery uses a much smaller incision between the ribs to access the heart (B). (Illustration by GGS Inc.) with a history of coronary artery disease can be evaluat- ed for this procedure. High risk patients with advanced age, at risk for stroke, or suffering peripheral vascular pump MIDCAB. With sternotomy, disease of the right disease, renal disease, or with poor lung function may and left coronary arteries can also be addressed by benefit from OPCAB and MIDCAB. OPCAB. The significance and location of the coronary Typically disease of the left anterior descending artery lesions may limit the success of the MIDCAB or coronary artery is treated with the technique called off- OPCAB procedure. Most practices have at least one sur- GALE ENCYCLOPEDIA OF SURGERY 975

Minimally invasive heart surgery geon skilled in performing revascularizations without Medical centers performing cardiac surgical WHO PERFORMS cardiopulmonary bypass. Of all coronary artery bypass THE PROCEDURE AND grafting procedures, approximately 10–20% are per- formed in this manner. WHERE IS IT PERFORMED? Description procedures are equipped to perform this proce- dure. A cardiothoracic, cardiovascular, or car- The patient receives cardiac monitoring during gen- diac surgeon receives additional training to eral anesthesia. Systemic anticoagulation is given to successfully complete this procedure. Special avoid clot formation from foreign surfaces and any peri- technology in stabilizer design is purchased by ods of artery blockage (occlusion). the institution and made available for the sur- geon to master. Within most clinical practices MIDCAB one surgeon becomes skilled in the technique. If cardiopulmonary bypass is not employed, the This one surgeon completes most procedures procedure is called an off-pump MIDCAB. The sur- off-pump with MIDCAB or OPCAB techniques geon performs an alternative incision (rather than a as necessary to revascularize the patient. midline sternotomy), typically a left anterior thoraco- tomy. The left internal mammary artery is dissected from the left chest wall. A stabilizer device is placed on the heart to provide support of the left anterior descend- OPCAB ing artery as the heart continues to beat. This device ap- plies gentle pressure or suction, mildly limiting cardiac The OPCAB procedure does not use cardiopulmonary function. The left internal mammary artery is sutured to bypass. The incision of choice can be a midline sternotomy the left anterior descending artery to bypass the block- or a left anterior thoracotomy (incision into the side). The age (anastomosis). midline sternotomy allows access to both the right and left internal mammary arteries. Additional vascular bypass If cardiopulmonary bypass is indicated, the surgeon conduits may be acquired by harvesting the saphenous inserts cannulae (small, flexible tubes) into the femoral vein (in the leg), gastroepiploic artery (near the stomach), vessels. Aortic occlusion and cardioplegia are adminis- or radial artery (in the arm). A stabilizing device is used to tered through a catheter advanced through the contralat- secure the coronary artery of choice. This device applies eral femoral artery into the aortic root (ascending aorta). gentle pressure or suction, mildly limiting cardiac function, This catheter has a balloon tip that stops blood flow to but providing better access to posterior and inferior vessels the coronary arteries when inflated, but allows selective of the heart. The surgeon makes the necessary anastomosis administration of cardioplegia (a solution that stops the to the targeted coronary arteries. If conduits other then the heart) to the coronary arteries. Angiography is per- mammary arteries are used they are connected to the as- formed to provide visualization of catheter placement. cending aorta to provide systemic blood flow. The surgeon performs an alternative incision (rather If an anticoagulant was administered, drugs are given than a midline sternotomy), typically a left anterior tho- to reverse the anticoagulant. Upon completion of the off- racotomy. The left internal mammary artery is dissected pump MIDCAB, MIDCAB, or OPCAB procedure, the from the left chest wall. Cardiopulmonary bypass can be chest is closed. If a midline sternotomy was performed, instituted with or without cardioplegic arrest. Cardio- stainless steel wires are implanted to hold the sternal plegic arrest requires cardiopulmonary bypass. The use bone together. Sutures are used to close the skin wound, of cardioplegic arrest makes this a non-beating heart and sterile bandages are applied as a wound dressing. procedure, but it is still considered MIDCAB. Cardio- plegic arrest of the heart occurs as the balloon tip of the catheter is inflated. The left internal mammary artery is Diagnosis/Preparation sutured to the left anterior descending artery to bypass An electrocardiogram detects the presence of acute the blockage (anastomosis). Once the anastomosis is coronary blockage (occlusion). A history of myocardial complete the balloon is deflated, allowing the heart to infarction can also be detected by electrocardiogram. Pa- begin to beat. Cardiopulmonary bypass is discontinued tients with a history of angina also are evaluated for once cardiac function is stabilized. The cannulae and coronary artery disease. Coronary angiography provides catheter are removed, and the groin wounds are closed the best diagnostic information about the extent and lo- with sutures. cation of the coronary artery disease. 976 GALE ENCYCLOPEDIA OF SURGERY

Aftercare QUESTIONS The patient receives continued cardiac monitoring in the intensive care unit. Once the patient is able to TO ASK THE DOCTOR breathe on his/her own, the breathing tube is removed (extubation), if it is not removed immediately post-oper- • Is there a surgeon associated with this prac- atively. Any medications to treat poor cardiac function or tice skilled with OPCAB or MIDCAB proce- Minimally invasive heart surgery manage blood pressure are discontinued as cardiac func- dures? tion improves and blood pressure stabilizes. Blood • Can the surgeon skilled in these procedures drainage tubes protruding from the chest cavity are re- evaluate the patient for an OPCAB or MID- moved once internal bleeding decreases. The patient also CAB procedure? may be equipped with external cardiac pacing to main- • How many procedures has the surgeon per- tain heart rate. The pacing is terminated once the heart is formed in the last year? In the last five years? beating at an adequate rate free of arrhythmia. A warm- • What is the surgeon’s reoperation rate in re- ing blanket may be used to warm the patient’s core tem- gards to length of graft patency? perature that was decreased by the surgical exposure. The duration of the post-operative hospital stay is re- duced by one to two days in these procedures. Pain also should be reduced. Homecare for the wound is described artery bypass grafting. When compared to traditional prior to discharge, and instructions for responding to ad- coronary artery bypass grafting, minimally invasive heart verse events after discharge also are given. Patients who surgery also is expected to result in a shorter hospital have undergone these procedures should expect to return stay, less pain, fewer blood transfusions, and quicker re- to normal activities sooner than those who have under- turn to normal activity. gone traditional coronary artery bypass grafting. Morbidity and mortality rates Risks MIDCAB MIDCAB can result in a higher rate of restenosis Conversion to a full sternotomy or sternotomy with (recurrence of narrowing of the arteries) then traditional cardiopulmonary bypass is expected in 1–2% of patients. coronary artery bypass grafting, but these numbers con- Redo procedures and reoperation can occur in over 5% tinue to decrease as experience with the procedure im- of patients, which is still lower than the risk of a second proves. Some patients may have to have the procedure procedure associated with balloon angioplasty and stent converted to a standard sternotomy with cardiopul- placement. Over 90% of all patients are expected to be monary bypass, if the anastomosis can not be completed free of adverse events. Complications most frequently from the MIDCAB approach. Rib fracture is the most involve rib fracture (over 10% of patients). Mortality as- common adverse event. Pericarditis also is a possible sociated with MICAB is low and is not seen during the complication. Supraventricular arrhythmias and ST seg- surgical procedure in most instances, but is associated ment elevation also may develop. with post-operative complications. In the event of systemic blood pressure abnormali- OPCAB ties, arrhythmia, poor surgical anastomosis, or poor expo- sure of the coronary blood vessels, OPCAB patients may Conversion to cardiopulmonary bypass may be re- require conversion to cardiopulmonary bypass for com- quired in patients if anastomosis cannot be completed pletion of the anastomosis. Post-operatively some pa- due to unstable blood pressure, arrhythmia, ischemia, tients may need additional surgery to control bleeding or poor anastomosis, or poor surgical access. The same op- to address poor sternal healing. This is related to the in- erative mortality is expected when compared to car- creased use of both internal mammary arteries for these diopulmonary bypass patients. The expected decrease in procedures. Cerebral complications and atrial fibrillation neurological events, renal dysfunction, pulmonary com- also may be experienced. These post-operative complica- plications, or arrhythmias has not yet been shown to be a tions are comparable to those seen in patients who have consistent benefit, therefore all of these complications undergone traditional coronary artery bypass grafting. can still occur. Normal results Alternatives Patency (openess) of the grafted vessels is expected Percutaneous balloon angioplasty and coronary to be the same as what is seen in traditional coronary stenting of the left anterior descending artery are suc- GALE ENCYCLOPEDIA OF SURGERY 977

Mitral valve repair Anastomosis—Connection of the bypassing blood Cardiopulmonary bypass—Use of the heart-lung KEY TERMS machine to provide systemic circulation cardiac vessel to the blocked blood vessel by surgical su- ture. The stitches may be made in continuous man- output and ventilation of the blood. ner or individual, with continuous being more common. The disadvantage of continuous suture Coronary occlusion—Obstruction of an artery that supplies the heart. When the artery is completely can be purse-stringing or cinching of the graft blocked, a myocardial infarction (heart attack) re- opening during knotting of the suture. sults; an incomplete blockage may result in angina. Angiography—Injecting dye into blood vessels so they can be seen on an x ray. Coronary stent—An artificial support device used to keep a coronary vessel open. Arrhythmia—Cardiac electrical signaling that gen- erates an ECG rhythm other than normal sinus Electrocardiography—A testing technique used to rhythm. measure electrical impulses from the heart in order to gain information about its structure or function. Balloon angioplasty—A procedure used to open an obstructed blood vessel. A small, balloon-tipped Myocardial infarction—Heart attack. catheter is inserted into the vessel and the balloon is inflated to widen the vessel and push the ob- Stabilizer—A device used to depress the move- structing material against the vessel’s walls. The re- ment of the area around the coronary artery where sult is improved blood flow through the vessel. the anastomosis is made. The stabilizer is used to provide a still, motionless field for suturing. Cannula—A small, flexible tube. Sternotomy—A surgical opening into the thoracic Cardioplegic arrest—Halting the electrical activity cavity through the sternum (breastbone). of the heart by delivery of a high potassium solu- tion to the coronary arteries. The arrested heart Thoracotomy—A surgical opening into the tho- provides a superior surgical field for operation. racic cavity. cessful alternative procedures. MIDCAB may be a pre- Moussa, I., et al. “Frequency of Early Occlusion and Stenosis ferred treatment when compared to balloon angioplasty in Bypass Grafts After Minimally Invasive Direct Coro- and stenting because fewer repeat interventions are re- nary Arterial Bypass Surgery.” The American Journal of quired. An additional alternative is traditional on-pump, Cardiology 88 (2001): 311–313. cardiopulmonary bypass; coronary artery bypass grafting Allison Joan Spiwak, MSBME is a powerful technique with a long record of safety and effectiveness since the 1960s. Resources Minor tranquilizers see Antianxiety drugs BOOKS Hensley, Frederick A., Donald E. Martin, and Glenn P. Gravlee, eds. A Practical Approach to Cardiac Anesthesia. 3rd ed. Philadelphia: Lippincott Williams & Wilkins 2003. PERIODICALS Mitral valve repair Borst, H. G. and F. W. Mohr. “The History of Coronary Artery Surgery—A Brief Review.” The Thoracic and Cardiovas- Definition cular Surgeon 49 (2001): 195–198. Mitral valve repair is a surgical procedure used to Holubkov, R., et al. “MIDCAB Characteristics and Results: the improve the function of a stenotic (narrowed), prolapsed, CardioThoracic Systems (CTS) Registry.” European Jour- or insufficient mitral valve of the heart. nal of Cardio-Thoracic Surgery 14, suppl.1 (1998): S25–S30. Lund, O., et al. “On-pump Versus Off-pump Coronary Artery Purpose Bypass: Independent Risk Factors and Off-Pump Graft Patency.” European Journal of Cardio-Thoracic Surgery The mitral valve can become diseased, preventing 20 (2001): 901–907. it from adequately controlling the direction of the blood 978 GALE ENCYCLOPEDIA OF SURGERY

flow between the left atrium and left ventricle. It also can become insufficient (regurgitant), letting blood WHO PERFORMS flow backwards into the left atrium (upper chamber) THE PROCEDURE AND from the left ventricle (lower chamber) during ventricu- WHERE IS IT PERFORMED? Mitral valve repair lar contraction (systole). The mitral valve also can be- come stenotic (narrowed), preventing the flow of blood Cardiothoracic and cardiovascular surgeons per- from the left atrium into the left ventricle during ven- form mitral valve repair. Surgeons are trained tricular filling (diastole). In mitral valve prolapse, one during their residency to perform these proce- or more of the mitral valve’s cusps protrude back into dures, although a certain level of skill is required the left atrium during ventricular contraction. Mitral for perfection of the technique. Medical centers valve repair is performed to improve the function of the that perform cardiac surgery are able to provide diseased valve so that it correctly controls the direction mitral valve repair. of blood flow. Demographics Mitral commissurotomy Approximately 65,000 valve repairs and replace- Mitral commissurotomy is used to repair mitral ments are performed in the United States annually. stenosis associated with rheumatic disease. The commis- Twice as many women as men are affected by mi- sures—openings between the valve leaflets—are manu- tral valve stenosis. About 60% of patients with mitral ally separated by the surgeon. Fused chordae tendineae valve stenosis have had rheumatic fever. After rheumat- (cords of connective tissue that connect the mitral valve ic fever there is usually a latency period of 10–20 years to the papillary muscle of the heart’s left ventricle) are before symptoms of mitral valve stenosis appear. The separated, along with papillary muscles. Calcium de- prevalence of mitral valve stenosis has declined in the posits may be removed from the valve leaflets. The left United States because there has been a decline in the atrial appendage is removed to reduce the risk of future number of cases of rheumatic fever. Mitral valve steno- thromboemboli (blood clot) generation. sis may be present at birth (congenital); however, it rarely occurs alone but rather in conjunction with other Chordae tendineae repair heart defects. The chordae tendineae can become lengthened or Mitral valve prolapse is the most common condition rupture, resulting in mitral valve prolapse. A skilled sur- of the heart valves, and is present in about 2% of the geon repairs the mitral valve structure by placing sutures general population. Recent studies indicate that similar in the valve leaflets to stabilize the valve structure. Typi- numbers of men and women have mitral valve prolapse. cally the posterior leaflet requires this type of repair. Having this condition does not guarantee that mitral in- sufficiency will develop. Patients with a history of Annuloplasty rheumatic fever, coronary artery disease, infective endo- carditis, or collagen vascular disease also may develop A flexible fabric ring is sutured to the valve annulus mitral insufficiency. to provide support and reconstruction for the patient’s valve annulus. The size of the ring is selected to match the patient’s own valve size. This repair allows the valve Description to function normally. Cardiac monitoring is instituted and general anesthe- The heart is closed with sutures. Deairing of the sia is provided. The surgeon uses a sternotomy to access heart is performed prior to removal of the cross clamp. the heart and great blood vessels. Anticoagulation is When the cross clamp is removed, deairing continues given as cannulae are inserted into the great vessels, to ensure that no air is delivered to the systemic circu- femoral vessels, or a combination. Cardiopulmonary by- lation. At this time a transesophageal echocardiogram pass is instituted. The heart is arrested as the cross clamp (TEE) may be used to test that the valve is functioning is applied to the ascending aorta to stop blood flow correctly and that the heart is free of air. If the surgeon through the organ. The surgeon opens the heart to visual- is not satisfied with the repair, mitral valve replace- ize the mitral valve. He/she may expose the mitral valve ment is performed. Once the surgeon is satisfied that by opening the right atrium and then opening the atrial the valve is working correctly, cardiopulmonary by- septum. Another approach requires a large left atrium that pass is terminated, anticoagulation is reversed, and the can be opened directly, making the mitral valve visible. cannulae are removed from the vessels. The sternoto- GALE ENCYCLOPEDIA OF SURGERY 979

Mitral valve repair • Is mitral valve repair the best treatment choice ment is considered. Severe pulmonary hypertension with QUESTIONS pulmonary artery systolic pressures greater than 60 mm TO ASK THE DOCTOR Hg is considered an indication for surgery. Left ventricu- lar ejection fraction less than 60% also is an indication for surgery. for my condition? • How many of these procedures has the sur- Aftercare geon performed in the last year? in the last The patient receives continued cardiac monitoring in five years? the intensive care unit and usually remains in intensive • What is the surgeon’s morbidity and mortality care for 24–48 hours after surgery. Ventilation support is rate with mitral valve repair? discontinued when the patient is able to breathe on his/her own. If mechanical circulatory support and in- • What will happen if the repair fails? otropic agents (a substance that influences the force of • What type of follow-up care is required dur- muscle contractions, e.g. digitalis) were needed during ing the first year after surgery and throughout the surgical procedure, they are discontinued as cardiac the rest of my life? function recovers. Tubes draining blood from the chest • What type of complications can be encoun- cavity are removed as bleeding from the surgical proce- tered both acute and chronic? dure decreases. Prophylactic antibiotics are given to prevent infective endocarditis and prevent the recurrence of rheumatic carditis. my is closed. Permanent stainless steel wires are used If the patient recovers normally, discharge from the to hold the sternum bone together. The skin incision is hospital occurs within a week of surgery. At discharge, closed with sutures, and sterile bandages are applied to the patient is given specific instructions about wound the wound. care and infection recognition, as well as contact infor- mation for the physician and guidelines about when a visit to the emergency room is indicated. Within three to Diagnosis/Preparation four weeks after discharge, the patient is seen for follow- up office visit with the physician, at which time physical Mitral valve stenosis is diagnosed by history, physi- status will have improved for evaluation. Thereafter, cal examination, listening to the sounds of the heart asymptomatic, uncomplicated patients are seen at yearly (cardiac auscultation), chest x ray, and ECG. Patients intervals. Few limitations are placed on patient activity may have no symptoms of a valve disorder or may have once recovery is complete. shortness of breath (dyspnea), fatigue, or pulmonary edema (fluid in the lungs). Other patients present with atrial fibrillation (a cardiac arrhythmia) or an embolic Risks event (result of a blood clot). Doppler echocardiogra- There are always risks associated with general anes- phy is the preferred diagnostic tool for evaluation of mi- thesia and cardiopulmonary bypass. Risks specifically tral valve stenosis, and can be performed in conjunction associated with mitral valve repair include embolism, with non-invasive exercise testing by treadmill or bicy- bleeding, or operative valvular endocarditis. When valve cle. Cardiac catheterization is reserved for patients repair does not produce adequate results, then increased who demonstrate discrepancies in Doppler testing. Both operative time is required to replace the mitral valve. If left- and right-heart catheterization should be performed the patient’s mitral valve is replaced with a mechanical in the presence of elevated pulmonary artery pressures. valve, the patient must take an anticoagulation drug, A diagnosis of mitral insufficiency requires a de- such as Coumadin, for the rest of his/her life. An inade- tailed patient history. Listening to the heart (ausculta- quately repaired valve, if left untreated, results in contin- tion) reveals the presence of a third heart sound. Chest x ued myocardial dysfunction resulting in pulmonary ray and ECG provide additional information. Again, edema, congestive heart failure, and systemic throm- Doppler echocardiography provides valuable informa- boemboli generation. tion. Exercise testing with Doppler echocardiography can show the true severity of the disease. Normal results After initial findings, patients may be followed with Patients treated by mitral valve repair for mitral in- repeat visits and testing to monitor disease progress. If sufficiency can expect improved myocardial function the patient has reached NYHA Class III or IV, replace- and relief of symptoms. Oxygen consumption by skele- 980 GALE ENCYCLOPEDIA OF SURGERY

Mitral valve repair Right atrium Mitral valve repair Incision A. B. Incision Heart-lung machine Sutures D. E. C. Section of posterior leaflet removed Mitral valve Annular ring Sutures F. During a mitral valve repair, the patient’s chest is opened along the sternum (A).The heart is connected to a heart-lung ma- chine, and an incision is made into the right atrium, or upper chamber of the heart (B), exposing the mitral valve (C). A sec- tion of the valve is removed, and the area is repaired with sutures (D and E). A flexible fabric ring may be stitched to the out- side of the valve to strengthen it, in a procedure called an annuloplasty (F). (Illustration by GGS Inc.) tal muscle continues to improve. Cardiac output im- Morbidity and mortality rates proves and pulmonary hypertension resolves over sev- Operative mortality associated with mitral valve re- eral months after the initial decrease in left atrial pres- pair for stenosis is 1–3%. The prognosis for restenosis sure, pulmonary artery pressure, and pulmonary arteri- (re-narrowing) is 30% at five years and 60% at nine olar resistance. years; additional surgery is required in 4–7% of patients Excellent results in terms of improved cardiac func- at five years. Eighty to 90% of patients whose mitral tion and symptom relief also are expected for patients valve stenosis was repaired by commissurotomy are that undergo mitral valve repair for mitral stenosis. complication free at five years after surgery. GALE ENCYCLOPEDIA OF SURGERY 981

Mitral valve repair Acute—Rapid onset. KEY TERMS NYHA heart failure classification—A classification system for heart failure developed by the New York Annulus—A ring-shaped structure. Anticoagulants—Drugs that are given to slow egories: I, symptoms with more than ordinary activi- blood clot formation. Heart Association. It includes the following four cat- ty; II, symptoms with ordinary activity; III, symptoms Cannula—A small, flexible tube. with minimal activity; IV, symptoms at rest. Cardiac catheterization—A diagnostic procedure Oxygen consumption—Oxygen utilization for en- (using a catheter inserted through a vein and ergy production. threaded through the circulatory system to the Rheumatic carditis—Inflammation of the heart heart) which does a comprehensive examination of muscle associated with acute rheumatic fever. how the heart and its blood vessels function. Rheumatic fever—An inflammatory disease that Cardiopulmonary bypass—Use of the heart-lung arises as a complication of untreated or inade- machine to provide systemic circulation cardiac quately treated strep throat infection. Rheumatic output and ventilation of the blood. fever can seriously damage the heart valves. Chordae tendineae—The strands of connective tis- Sternotomy—A surgical opening into the thoracic sue that connect the mitral valve to the papillary cavity through the sternum (breastbone). muscle of the heart’s left ventricle. Systemic circulation—Circulation supplied by the Chronic—Long-term. aorta including all tissue and organ beds, except Commissures—The normal separations between the alveolar sacs of the lungs used for gas ex- the valve leaflets. change and respiration. Doppler echocardiography—A testing technique Thromboemboli—Blood clots that develop in the that uses Doppler ultrasound technology to evalu- circulation and lodge in capillary beds of tissues ate the pattern and direction of blood flow in the and organs. heart. Transesophageal echocardiography—A diagnostic Endocarditis—Infection of the heart endocardium test using an ultrasound device that is passed into tissue, the inner most tissue and structures of the the esophagus of the patient to create a clear image heart. of the heart muscle and other parts of the heart. Mitral valve repair for mitral insufficiency is the the absence of mitral valve replacement, mitral valve preferred approach because it preserves the valvular ap- repair is indicated. paratus and left ventricular function. It also eliminates the risk of mechanical valve failure and the need for life- Resources long anticoagulation. BOOKS Hensley, Frederick A., Donald E. Martin, and Glenn P. Gravlee, Alternatives eds. A Practical Approach to Cardiac Anesthesia. 3rd ed. The asymptomatic patient with a history of rheumat- Philadelphia: Lippincott Williams & Wilkins, 2003. ic fever can be treated with prophylactic antibiotics and Topol, Eric J., ed. Textbook of Interventional Cardiology. followed until symptoms are appear. If atrial fibrillation Philadelphia: W. B. Saunders, 2002. develops antiarrhythmic medications can be used for treatment. Atrial defibrillation may relieve atrial fibril- PERIODICALS lation. Anticoagulants may be prescribed to prevent the Bonow, R., et al. “ACC/AHA Guidelines for the Management occurrence of systemic embolization. of Patients with Valvular Heart Disease.” Journal of the American College of Cardiology 32 (November 1998): Mitral valve repair for mitral regurgitation is not 1486–1582. as successful if the anterior leaflet is involved. Brown, Katherine Kay. “Minimally Invasive Valve Surgery” Rheumatic, ischemic, or calcific diseases decrease the Critical Care Nursing Quarterly 20 (February 1998): likelihood of repair in even the most skilled hands. In 40–52. 982 GALE ENCYCLOPEDIA OF SURGERY

Wiegand, Debra Lynn-McHale. “Advances in Cardiac Surgery: Valve Repair” Critical Care Nurse 23 (April 2003): 72–90. WHO PERFORMS THE PROCEDURE AND Allison Joan Spiwak, MSBME WHERE IS IT PERFORMED? Cardiothoracic and cardiovascular surgeons pro- Mitral valve replacement vide surgical treatment. Surgeons are trained dur- ing the residency to perform these procedures. Medical centers that perform cardiac surgery are Mitral valve replacement able to provide mitral valve replacement. Definition Mitral valve replacement is a surgical procedure in which the diseased mitral valve of the heart is replaced tral insufficiency will develop. Patients with a history of by a mechanical or biological tissue valve. rheumatic fever, coronary artery disease, infective endo- carditis, or collagen vascular disease also may develop Purpose mitral insufficiency. The mitral valve can become diseased, preventing it from adequately controlling the direction of the flow of Description blood between the left atrium and left ventricle. It also Cardiac monitoring is instituted and general anes- can become insufficient (regurgitant) and allow blood to thesia is provided. The surgeon uses a sternotomy to ac- flow backwards into the left atrium from the left ventri- cess the heart and great blood vessels. Anticoagulation cle during ventricular contraction (systole). In addition, is given as cannulae are inserted into the large vessels of the mitral valve can become stenotic (narrowed), pre- the heart, femoral vessels, or a combination. Cardiopul- venting the flow of blood from the left atrium into the monary bypass is instituted. The heart is arrested as the left ventricle during ventricular filling (diastole). In mi- cross clamp is applied to the ascending aorta to stop tral valve prolapse, one or more of the mitral valve’s blood flow through the organ. The surgeon opens the cusps protrude back into the left atrium during ventricu- heart to visualize the mitral valve. He/she may expose lar contraction. Mitral valve replacement is performed to the mitral valve by opening the right atrium and then remove the diseased valve and provide a new mechanical opening the atrial septum. Another approach requires a valve or biological tissue valve that correctly controls the large left atrium that can be opened directly, making the direction of blood flow. mitral valve visible. Demographics Next, the surgeon cuts the diseased valve away from the valve annulus (outer ring). The annulus is sized so Approximately 65,000 valve repairs and replace- that the proper size of valve can be selected for the pa- ments are performed in the United States each year. tient’s anatomy. Sutures are applied around the valve an- Twice as many women as men are affected by mi- nulus, the valve is sutured into place, and tied into posi- tral valve stenosis. About 60% of patients with mitral tion. The atrial septum is closed with suture or left to valve stenosis have had rheumatic fever. After rheumat- heal naturally, and the heart is closed with sutures. ic fever there is usually a latency period of 10–20 years Deairing of the heart is performed prior to removal before symptoms of mitral valve stenosis appear. The of the cross clamp. When the cross clamp is removed, prevalence of mitral valve stenosis has declined in the deairing continues to ensure that no air is delivered to the United States because there has been a decline in the systemic circulation. At this time a transesophageal number of cases of rheumatic fever. Mitral valve steno- echocardiogram (TEE) may be used to test that the valve sis may be present at birth (congenital); however, it is functioning correctly and that the heart is free of air. rarely occurs alone but rather in conjunction with other Once the surgeon is satisfied that the valve is working heart defects. correctly, cardiopulmonary bypass is terminated, antico- Mitral valve prolapse is the most common condi- agulation is reversed, and the cannulae are removed from tion of the heart valves, and is present in about 2% of the vessels. The sternotomy is closed. Permanent stain- the general population. Recent studies indicate that sim- less steel wires are used to hold the sternum bone togeth- ilar numbers of men and women have mitral valve pro- er. The skin incision is closed with sutures, and sterile lapse. Having this condition does not guarantee that mi- bandages are applied to the wound. GALE ENCYCLOPEDIA OF SURGERY 983

Mitral valve replacement • Is mitral valve replacement the best treatment by treadmill or bicycle. Cardiac catheterization is re- served for patients who demonstrate discrepancies in QUESTIONS Doppler testing. Both left- and right-heart catheterization TO ASK THE DOCTOR should be performed in the presence of elevated pul- monary artery pressures. option for my condition? A diagnosis of mitral insufficiency requires a de- • How many of these procedures has the sur- tailed patient history. Listening to the heart (ausculta- geon performed in the last year? in the last five years? ray and ECG provide additional information. Again, Doppler echocardiography provides valuable informa- • What is the surgeon’s morbidity and mortality tion) reveals the presence of a third heart sound. Chest x rate with mitral valve replacement? tion. Exercise testing with Doppler echocardiography can show the true severity of the disease. • What type of replacement valve, biological tissue or mechanical, is best for me? After initial findings, patients may be followed with • What are the pros and cons of each valve repeat visits and testing to monitor disease progress. If type? the patient has reached NYHA Class III or IV, replace- ment is considered. Severe pulmonary hypertension with • What type of follow-up care is required dur- pulmonary artery systolic pressures greater than 60 mm ing the first year after valve implant and for Hg is considered an indication for surgery. Left ventricu- the rest of my life? lar ejection fraction (a measure of output) less than 60% • What types of complications are associated also is an indication for surgery. with this surgery? Aftercare The patient receives continued cardiac monitoring in A heart valve is a structure within the heart that pre- the intensive care unit and usually remains in intensive vents the backflow of blood by opening and closing with care for 24–48 hours after surgery. Ventilation support is each heartbeat. Replacement heart valves are either me- discontinued when the patient is able to breathe on chanical or biological tissue valves. For patients under his/her own. If mechanical circulatory support and in- the age of 65, the mechanical valve offers superior otropic agents (a substance that influences the force of longevity, but the use of this type of valve requires that muscle contractions, e.g. digitalis) were needed during the patient take an anticoagulation drug for the rest of the surgical procedure, they are discontinued as cardiac his/her life. The biological tissue valve does not require function recovers. Tubes draining blood from the chest anticoagulation therapy, but this type of valve is prone to cavity are removed as bleeding from the surgical proce- deterioration leading to reoperation, particularly in dure decreases. Prophylactic antibiotics are given to those under the age of 50. Women who may want to have prevent infective endocarditis and the recurrence of children after a valve replacement should usually receive rheumatic carditis. a biological tissue valve, because the anticoagulant (Coumadin/warfarin) most often prescribed for patients Both mechanical and biological tissue valves re- with mechanical valves is associated with fetal birth de- quire anticoagulation therapy after surgery, and while fects. Aspirin can be substituted for warfarin in certain patients are hospitalized their anticoagulant status is circumstances. monitored and dosages are adjusted accordingly. Pa- tients with biological tissue valves can discontinue anti- coagulation therapy within three months of implanta- Diagnosis/Preparation tion, but those with mechanical valves must take an an- ticoagulant (aspirin, warfarin, or a combination of the Mitral valve stenosis is diagnosed by history, physi- two) for the rest of their lives. These patients are regu- cal examination, listening to the sounds of the heart larly monitored for INR values, which are maintained (cardiac auscultation), chest x ray, and ECG. Patients between 2.0 and 4.5. may have no symptoms of a valve disorder or may have shortness of breath (dyspnea), fatigue, or frank pul- If the patient recovers normally, discharge from the monary edema. Other patients present with atrial fibrilla- hospital occurs within a week of surgery. At discharge, tion (a cardiac arrhythmia) or an embolic event. Doppler the patient is given specific instructions about wound echocardiography is the preferred diagnostic tool for care and infection recognition, as well as contact infor- evaluation of mitral valve stenosis, and it can be per- mation for the physician and guidelines about when a formed in conjunction with non-invasive exercise testing visit to the emergency room is indicated. Within three or 984 GALE ENCYCLOPEDIA OF SURGERY

KEY TERMS Annulus—A ring-shaped structure. Mechanical valve—There are three types of me- chanical valve: ball valve, disk valve, and bileaflet Mitral valve replacement Anticoagulants—Drugs that are given to slow valve. blood clot formation. NYHA heart failure classification—A classification Biological tissue valve—An autograft is a valve that system for heart failure developed by the New York comes from the patient, usually the pulmonary Heart Association. It includes the following four cat- valve. An autologous pericardial valve is construct- egories: I, symptoms with more than ordinary activi- ed from the patient’s pericardium (the fibrous sac ty; II, symptoms with ordinary activity; III, symptoms that surrounds the heart and the roots of the great with minimal activity; IV, symptoms at rest. vessels and also forms the outer layer of the heart wall) at the time of surgery. A homograft (or allo- Rheumatic carditis—Inflammation of the heart graft) valve is a valve harvested from a human ca- muscle associated with acute rheumatic fever. daver. A porcine (pig) heterograft is a porcine tissue valve that is rendered bioacceptable by destroying Rheumatic fever—An inflammatory disease that antigenicity with glutaraldehyde sterilization. arises as a complication of untreated or inade- quately treated strep throat infection. Rheumatic Cardiac catheterization—A diagnostic procedure fever can seriously damage the heart valves. (using a catheter inserted through a vein and threaded through the circulatory system to the Sternotomy—A surgical opening into the thoracic heart) which does a comprehensive examination of cavity through the sternum (breastbone). how the heart and its blood vessels function. Systemic circulation—Circulation supplied by the Cardiopulmonary bypass—Use of the heart-lung aorta including all tissue and organ beds, except machine to provide systemic circulation cardiac the alveolar sacs of the lungs used for gas ex- output and ventilation of the blood. change and respiration. Commissures—The normal separations between Thromboemboli—Blood clots that develop in the the valve leaflets. circulation and lodge in capillary beds of tissues Doppler echocardiography—A testing technique and organs. that uses Doppler ultrasound technology to evaluate the pattern and direction of blood flow in the heart. Transesophageal echocardiography—A diagnostic test using an ultrasound device that is passed into Endocarditis—Infection of the heart endocardium tis- the esophagus of the patient to create a clear image sue, the inner most tissue and structures of the heart. of the heart muscle and other parts of the heart. four weeks after discharge, the patient is seen for follow- Normal results up office visit with the physician, at which time physical Patients treated by mitral valve replacement for mi- status will have improved for evaluation. Thereafter, tral insufficiency can expect relief of symptoms. Im- asymptomatic, uncomplicated patients are seen at yearly provement in myocardial function is not likely, but the intervals. Few limitations are placed on patient activity current status is preserved. For patients who received once recovery is complete. mechanical valves, anticoagulation therapy is continued lifelong to elevate the INR to between 2.0 and 4.5, de- Risks pending on the type of mechanical valve implanted. There are always risks associated with general anes- Since thromboembolic complications are associated thesia and cardiopulmonary bypass. Risks specifically with initial implant of biological tissue valves, patients associated with mitral valve replacement include em- who received this type of valve take an anticoagulant for bolism, bleeding, and operative valvular endocarditis. three months after surgery to maintain an INR of Hemolysis (the breakdown of red blood cells) is associ- 2.0–3.0. If non-cardiac surgery or dental care is needed, ated with certain types of mechanical valves, but is not a the anticoagulation therapy is adjusted to prevent bleed- contraindication for implantation. ing complications. GALE ENCYCLOPEDIA OF SURGERY 985

Patients who undergo mitral valve replacement for Modified radical mastectomy mitral stenosis can expect excellent improvement of rounding tissue, and nearby lymph nodes that are affect- Modified radical mastectomy symptoms. Those patients with symptoms consistent Definition with NYHA class IV before surgery have better out- come after mitral valve replacement compared to no A surgical procedure that removes the breast, sur- treatment. ed by cancer. Morbidity and mortality rates Purpose Mitral valve replacement carries a less than 5% risk of death in young, healthy patients. With increased age, The purpose for modified radical mastectomy is additional medical problems, or pulmonary hypertension the removal of breast cancer (abnormal cells in the the risk of death increases to 10–20%. Post-replacement breast that grow rapidly and replace normal healthy tis- the five year survival is 80%. Patients over the age of 75 sue). Modified radical mastectomy is the most widely have poorer outcomes when mitral valve replacement is used surgical procedure to treat operable breast cancer. used to treat mitral insufficiency. This procedure leaves a chest muscle called the pec- toralis major intact. Leaving this muscle in place will provide a soft tissue covering over the chest wall and a Alternatives normal-appearing junction of the shoulder with the an- The asymptomatic patient with a history of rheumat- terior (front) chest wall. This sparing of the pectoralis ic fever can be treated with prophylactic antibiotics and major muscle will avoid a disfiguring hollow defect followed until symptoms are appear. If atrial fibrillation below the clavicle. Additionally, the purpose of modi- develops, antiarrhythmic medications can be used for fied radical mastectomy is to allow for the option of treatment. Atrial defibrillation may relieve atrial fibril- breast reconstruction, a procedure that is possible, if lation. Anticoagulants may be prescribed to prevent the desired, due to intact muscles around the shoulder of occurrence of systemic embolization. The patient with the affected side. The modified radical mastectomy symptoms may benefit from percutaneous mitral balloon procedure involves removal of large multiple tumor valvotomy. Surgery to perform a commissurotomy may growths located underneath the nipple and cancer cells be used instead of valve replacement. on the breast margins. Mitral valve insufficiency or prolapse that develops atrial fibrillation should be treated with drugs to regulate Demographics the heart rhythm or atrial defibrillation. Anticoagulation therapy is employed to avoid systemic emboli during pe- The highest rates of breast cancer occur in Western riods of atrial fibrillation. Mitral valve repair maybe countries (more than 100 cases per 100,000 women) and beneficial instead of mitral valve replacement. the lowest among Asian countries (10–15 cases per 100,000 women). Men can also have breast cancer, but Resources the incidence is much less when compared to women. There is a strong genetic correlation since breast cancer BOOKS is more prevalent in females who had a close relative Hensley, Frederick A., Donald E. Martin, and Glenn P. Gravlee, (mother, sister, maternal aunt, or maternal grandmother) eds. A Practical Approach to Cardiac Anesthesia. 3rd ed. with previous breast cancer. Increased susceptibility for Philadelphia: Lippincott Williams & Wilkins, 2003. development of breast cancer can occur in females who Topol, Eric J., ed. Textbook of Interventional Cardiology. never breastfed a baby, had a child after age 30, started Philadelphia: W. B. Saunders, 2002. menstrual periods very early, or experienced menopause PERIODICALS very late. Bonow, R., et al. “ACC/AHA Guidelines for the Management of In the United States, there were approximately Patients with Valvular Heart Disease.” Journal of the Ameri- can Collge of Cardiology 32 (November 1998): 1486–1582. 175,000 cases of breast cancer in 1999 with more than Brown, Katherine Kay. “Minimally Invasive Valve Surgery.” Crit- 43,000 deaths. Breast cancer accounts for 30% of all ical Care Nursing Quarterly 20 (February 1998): 40–52. cancer diagnosed in American women and for 16% of all Sadovsky, Richard. “Using Warfarin After Heart Valve Replace- cancer deaths. Breast cancer is a worldwide public health ment.” American Family Physician 61 (April 1, 2000): 2219. problem since there are approximately one million new cases diagnosed annually. A woman’s lifetime risk of de- Allison Joan Spiwak, MSBME veloping breast cancer is one in eight. The incidence rose 986 GALE ENCYCLOPEDIA OF SURGERY

Woman with scars from a modified radical mastectomy. (Biophoto Associates/Science Source. Reproduced by permission.) Modified radical mastectomy 21% from 1973 to 1990, but in recent years there has axillary surgery, breast reconstruction can be performed, been a decline. if desired by the patient. Description Diagnosis/Preparation The surgeon’s goal during this procedure is to mini- Modified radical mastectomy is a surgical proce- mize any chance of local/regional recurrence; avoid any dure to treat breast cancer. In order for this procedure loss of function; and maximize options for breast recon- to be an operable option, a definitive diagnosis of struction. Incisions are made to avoid visibility in a low breast cancer must be established. The first clinical sign neckline dress or bathing suit. An incision in the shape of for approximately 80% of women with breast cancer is an ellipse is made. The surgeon removes the minimum a mass (lump) located in the breast. A lump can be dis- amount of skin and tissue so that remaining healthy tis- covered by monthly self-examination or by a health sue can be used for possible reconstruction. Skin flaps professional who can find 10–25% of breast cancers are made carefully and as thinly as possible to maximize that are missed by yearly mammograms (a low radia- removal of diseased breast tissues. The skin over a tion x ray of the breasts). A biopsy can be performed to neighboring muscle (pectoralis major fascia) is removed, examine the cells from a lump that is suspicious for after which the surgeon focuses in the armpit (axilla, ax- cancer. The diagnosis of the extent of cancer and spread illary) region. In this region, the surgeon carefully identi- to regional lymph nodes determines the treatment fies vital anatomical structures such as blood vessels course (i.e., whether surgery, chemotherapy, or radia- (veins, arteries) and nerves. Accidental injury to specific tion therapy, either singly or in combinations). Staging nerves like the medial pectoral neurovascular bundle will the cancer can estimate the amount of tumor, which is result in destruction of the muscles that this surgery at- important not only for diagnosis but for prognosis (sta- tempts to preserve, such as the pectoralis major muscle. tistical outcome of the disease process). Patients with a In the armpit region, the surgeon carefully protects the type of breast cancer called ductal carcinoma in situ vital structures while removing cancerous tissues. After (DCIS), which is a stage 0 cancer, have the best out- GALE ENCYCLOPEDIA OF SURGERY 987

Modified radical mastectomy Modified radical mastectomy Superior skin flap nodes Pectoralis Incision Lymph major Fascia Mammary glands A. B. C. Sutures Scar tissue Drains placed under skin D. E. In a modified radical mastectomy, the skin on the breast is cut open (A).The skin is pulled back, and the tumor, lymph nodes, and breast tissue are removed (B and C).The incision is closed (D). (Illustration by GGS Inc.) come (nearly all these patients are cured of breast can- with stage IV metastatic breast cancer survive 10 years cer). Persons who have cancerous spread to other dis- after diagnosis. tant places within the body (metastases) have stage IV It is also imperative to assess the degree of cancer- cancer and the worst prognosis (potential for survival). ous spread to lymph nodes within the armpit region. Of Persons affected with stage IV breast cancer have es- primary importance to stage determination and regional sentially no chance for cure. lymph node involvement is identification and analysis Persons affected with breast cancer must undergo of the sentinel lymph node. The sentinel lymph node is the staging of the cancer to determine the extent of can- the first lymph node to which any cancer would spread. cerous growth and possible spread (metastasis) to distant The procedure for sentinel node biopsy involves inject- organs. Patients with stage 0 disease have noninvasive ing a radioactively labeled tracer (technetium 99) or a cancer with a very good outcome. Stages I and II are blue dye (isosulphan blue) into the tumor site. The trac- early breast cancer, without lymph node involvement er or dye will spread through the lymphatic system to (stage I) and with node positive results (stage II). Per- the sentinel node, which should be surgically removed sons with stage III disease have locally advanced disease and examined for the presence of cancer cells. If the and about a 50% chance for five-year survival. Stage IV sentinel node and one or two other neighboring lymph disease is the most severe since the breast cancer cells nodes are negative, it is very likely that the remaining have spread through lymph nodes to distant areas and/or lymph nodes will not contain cancerous cells, and fur- other organs in the body. It is very unlikely that persons ther surgery may not be necessary. 988 GALE ENCYCLOPEDIA OF SURGERY

Once a breast lump (mass) has been identified by immediate signs of risk following surgery include fever, mammography or physical examination, the patient redness in the incision area, unusual drainage from the in- should undergo further evaluation to histologically cision, and increasing pain. If any of these signs develop, (studying the cells) identify or rule out the presence of it is imperative to call the surgeon immediately. cancer cells. A procedure called fine-needle aspiration al- lows the clinician to extract cells directly from the lump Normal results Modified radical mastectomy for further evaluation. If a diagnosis cannot be established by fine-needle biopsy, the surgeon should perform an If no complications develop, the surgical area should open biopsy (surgical removal of the suspicious mass). completely heal within three to four weeks. After mastecto- Preparation for surgery is imperative. The patient should my, some women may undergo breast reconstruction plan for both direct care and recovery time after modified (which can be done during mastectomy). Recent studies radical mastectomy. Preparation immediately prior to have indicated that women who desire cosmetic reconstruc- surgery should include no food or drink after midnight tive surgery have a higher quality of life and better sense of before the procedure. Post-surgical preparation should in- well-being than those who do not utilize this option. clude caregivers to help with daily tasks for several days. Morbidity and mortality rates Aftercare The outcome of breast cancer is very dependent of the stage at the time of diagnosis. For stage 0 disease After breast cancer surgery, women should undergo (5–10% of the cases), the five-year survival is 99%. For frequent testing to ensure early detection of cancer recur- stage I (early/lymph node negative), which comprises rence. It is recommended that annual mammograms, 40–45% of total cases, the five-year survival is 85–95%. physical examination, or additional tests (biopsy) be per- For stage II (early/lymph node positive), which compris- formed annually. Aftercare can also include psychothera- es 35–40% of total cases, the five-year survival decreas- py since mastectomy is emotionally traumatic. Affected es to 65–75%. For stage III disease (locally advanced), women may be worried or have concerns about appear- which accounts for 10–15% of total cases, the five-year ance, the relationship with their sexual partner, and possi- survival is 45–50%. Women with stage IV (metastatic) ble physical limitations. Community-centered support breast cancer account for about 7% of total cases; the groups usually made up of former breast cancer surgery five-year survival is 20–30%. Less than 1% of these patients can be a source of emotional support after women survive past 10 years. surgery. Patients may stay in the hospital for one to two days. For about five to seven days after surgery, there will be one or two drains left inside to remove any extra fluid Alternatives from the area after surgery. Usually, the surgeon will pre- There are no real alternatives to mastectomy. Surgi- scribe medication to prevent pain. Movement restriction cal requirement is clear since mastectomy is recom- should be specifically discussed with the surgeon. mended for tumors with dimensions over 2 in (5 cm). Additional treatment (adjuvant) is typically recommend- Risks ed with chemotherapy and/or radiation therapy to de- stroy any remaining cancer during surgery. Modified There are several risks associated with modified radi- radical mastectomy is one of the standard treatment rec- cal mastectomy. The procedure is performed under gener- ommendations for stage III breast cancer. al anesthesia, which itself carries risk. Women may have short-term pain and tenderness. The most frequent risk of Resources breast cancer surgery (with extensive lymph node re- BOOKS moval) is edema, or swelling of the arm, which is usually Noble, John. Textbook of Primary Care Medicine, 3rd edition. mild, but the presence of fluid can increase the risk of in- St. Louis: Mosby, Inc., 2001. fection. Leaving some lymph nodes intact instead of re- Townsend, Courtney. Sabiston Textbook of Surgery, 16th edi- moving all of them may help lessen the likelihood of tion. St. Louis: W. B. Saunders Company, 2001. swelling. Nerves in the area may be damaged. There may be numbness in the arm or difficulty moving shoulder PERIODICALS muscles. There is also the risk of developing a lump scar Fiorica, James. “Prevention and Treatment of Breast Cancer.” Ob- (keloid) after surgery. Another risk is that surgery did not stetrics and Gynecology Clinics 28 no. 4 (December 2001). remove all the cancer cells and that further treatment may ORGANIZATIONS be necessary (with chemotherapy and/or radiotherapy). American Cancer Society. (800) ACS-2345. <http://www.can- By far, the worst risk is recurrence of cancer. However, cer.org.>. GALE ENCYCLOPEDIA OF SURGERY 989

Mohs surgery Lymphatic system—A system that filters excess tis- • The cancer grows rapidly or uncontrollably. KEY TERMS Demographics sue fluids through lymph nodes to return to the According to the National Cancer Institute (NCI), bloodstream. about one million people in the United States are diag- nosed with skin cancer every year. The two most com- mon types of skin cancer are basal cell carcinoma and squamous cell carcinoma, with basal cell carcinoma ac- Cancer support groups. <http://www.cancernews.com>. counting for more than 90% of all of skin cancers. Y-ME National Breast Cancer Organization. <http://www. y-me.org.>. Melanoma is the most serious type of skin cancer. Each year in the United States more than 53,600 people Laith Farid Gulli, MD are diagnosed with melanoma, and it is becoming more Nicole Mallory, MS, PA-C and more common, especially among Western coun- tries. In the United States, the percentage of people who develop melanoma has more than doubled in the past 30 years. Mohs surgery Definition Description There are two types of Mohs surgery: fresh-tissue Mohs surgery, also called Mohs micrographic technique and fixed-tissue technique. Of the surgeons surgery, is a precise surgical technique that is used to re- who perform Mohs surgery, 72% use only the fresh-tis- move all parts of cancerous skin tumors, while preserv- sue technique. The remaining surgeons (18%) use both ing as much healthy tissue as possible. techniques. However, the fixed-tissue technique is used in fewer than 5% of patients. The main difference be- Purpose tween the two techniques is in the preparatory steps. Mohs surgery is used to treat such cancers of the skin as basal cell carcinoma, squamous cell carcinoma, Fresh-tissue technique and melanoma. Fresh-tissue Mohs surgery is performed under Malignant skin tumors may occur in strange, asym- local anesthesia for tumors of the skin. The area to be metrical shapes. The tumor may have long finger-like excised is cleaned with a disinfectant solution and a projections that extend across the skin (laterally) or sterile drape is placed over the site. The surgeon may down into the skin. Because these extensions may be outline the tumor using a surgical marking pen, or a composed of only a few cells, they cannot be seen or felt. dye. A local anesthetic (lidocaine plus epinephrine) is Standard surgical removal (excision) may miss these injected into the area. Once the local anesthetic has cancerous cells leading to recurrence of the tumor. To as- taken effect, the main portion of the tumor is excised sure removal of all cancerous tissue, a large piece of skin (debulked) using a spoon-shaped tool (curette). To de- needs to be removed. This causes a cosmetically unac- fine the area to be excised and to allow for accurate ceptable result, especially if the cancer is located on the mapping of the tumor, the surgeon makes identifying face. Mohs surgery enables the surgeon to precisely ex- marks around the lesion. These marks may be made cise the entire tumor without removing excessive with stitches, staples, fine cuts with a scalpel, or tempo- amounts of the surrounding healthy tissue. rary tattoos. One layer of tissue is carefully excised Mohs surgery is performed when: (first Mohs excision), cut into smaller sections, and taken to the laboratory for analysis. • The cancer was treated previously and recurred. • Scar tissue exists in the area of the cancer. If cancerous cells are found in any of the tissue sections, a second layer of tissue is removed (second • The cancer is in at least one area where it is important Mohs excision). Because only the sections that have to preserve healthy tissue for maximum functional and cancerous cells are removed, healthy tissue can be cosmetic result, such as on the eyelids, the nose, the spared. The entire procedure, including surgical repair ears, and the lips. of the wound, is performed in one day. Surgical repair • The edges of the cancer cannot be clearly defined. may be performed by the Mohs surgeon, a plastic sur- 990 GALE ENCYCLOPEDIA OF SURGERY

WHO PERFORMS QUESTIONS THE PROCEDURE AND TO ASK THE DOCTOR Mohs surgery WHERE IS IT PERFORMED? • How long have you been performing Mohs Mohs surgery is performed in a hospital setting surgery? by highly trained surgeons who are specialists • Will you use the fresh-tissue or fixed-tissue both in dermatology and pathology. With their technique? extensive knowledge of the skin and unique • Will I have to alter the use of my current pathologic skills, they are able to remove only medications for this procedure? diseased tissue, preserving healthy tissue and minimizing the cosmetic impact of the surgery. • What will you do if you don’t find the border Only physicians who have also completed a of the cancerous lesion? residency in dermatology are qualified for • How will the wound be repaired? Mohs surgical training. The surgery is very often • Will I need a plastic surgeon to repair the performed on an outpatient basis, usually in wound? one day. • What is the cure rate for this type of cancer when treated by Mohs surgery? • What is the chance that the tumor will recur? geon, or another specialist. In certain cases, wounds • How often will I have follow-up appointments? may be allowed to heal naturally. Fixed-tissue technique With fixed-tissue Mohs surgery, the tumor is de- cohol, vitamin E, and fish oil tablets should be avoided bulked, as described previously. Trichloracetic acid is prior to the procedure. The patient who uses over-the- applied to the wound to control bleeding, followed by a counter aspirin or the prescription blood-thinners, preservative (fixative) called zinc chloride. The wound brands Coumadin (warfarin, generically) and heparin is dressed and the tissue is allowed to fix for six to 24 should consult with the prescribing physician before ad- hours, depending on the depth of the tissue involved. justing the dosage of any drug. This period, called the fixation period, can be painful to the patient. The first Mohs excision is performed as de- Aftercare scribed; however, anesthesia is not required because the tissue is dead. If cancerous cells are found, fixative is Patients should expect to receive specific wound applied to the affected area for an additional six to 24 care instructions from their physician or surgeon. Gener- hours. Excisions are performed in this sequential ally, however, wounds that have been repaired with ab- process until all cancerous tissue is removed. Surgical sorbable stitches or skin grafts should be kept covered repair of the wound may be performed once all fixed with a bandage for one week. Wounds that have been re- tissue has sloughed off—usually a few days after the paired using nonabsorbable stitches should also be cov- last excision. ered with a bandage that should be replaced daily until the stitches are removed one to two weeks later. Signs of Diagnosis/Preparation infection (e.g., redness, pain, drainage) should be report- ed to the physician immediately. An oncologist will have diagnosed the skin cancer of the patient using such standard cancer diagnostic tools Risks as biopsy of the tumor. Using the fresh-tissue technique on a large tumor re- To prepare for surgery, and under certain conditions quires large amounts of local anesthetic that can be (such as the location of the skin tumor or health status of toxic. Complications of Mohs surgery include infection, the patient), antibiotics may be given to the patient prior bleeding, scarring, and nerve damage. to the procedure; this is known as prophylactic antibiotic treatment. Patients are encouraged to eat prior to surgery Tumors spread in unpredictable patterns. Sometimes and also to bring along snacks in case the procedure be- a seemingly small tumor is found to be quite large and come lengthy. To reduce the risk of bleeding, the use of widespread, resulting in a much larger excision than was nonsteroidal anti-inflammatory drugs (NSAIDs), al- anticipated. GALE ENCYCLOPEDIA OF SURGERY 991

ORGANIZATIONS Multiple-gated acquisition (MUGA) scan KEY TERMS American Society for Mohs Surgery. Private Mail Box 391, 5901 Warner Avenue, Huntington Beach, CA 92649-4659. Carcinoma—Cancer that begins in the cells that (714) 840-3065. (800) 616-ASMS (2767). <www.mohs cover or line an organ. surgery.org>. Fixative—A chemical that preserves tissue without OTHER destroying or altering the structure of the cells. “About Mohs Micrographic Surgery.” Mohs College. <www. Fixed—A term used to describe chemically pre- mohscollege.org/AboutMMS.html>. served tissue. Fixed tissue is dead so it does not bleed or sense pain. Belinda Rowland, Ph.D. Monique Laberge, Ph.D. Mohs excision—Referring to the excision of one layer of tissue during Mohs surgery. Also called stage. Mometasone see Corticosteroids MR see Magnetic resonance imaging Normal results MRA see Magnetic resonance imaging Most skin cancers treated by Mohs surgery are com- MRI see Magnetic resonance imaging pletely removed with minimal loss of normal skin. MRS see Magnetic resonance imaging Morbidity and mortality rates MUGA scan see Multiple-gated acquisition Mohs surgery provides high cure rates for malignant (MUGA) scan skin tumors. For instance, the five-year cure rate for basal cell carcinoma treated by Mohs surgery is higher than 99%. The frequency of recurrence is much lower with Mohs surgery is much lower than with conventional surgical excision—less than 1%. Multiple-gated acquisition (MUGA) scan Alternatives Mohs surgery is a specialized technique that is not in- Definition dicated for the treatment of every type of skin cancer, and The multiple-gated acquisition (MUGA) scan, also is most appropriately used under specific, well-defined called a cardiac blood pool study, is a non-invasive nu- circumstances. The majority of basal cell carcinomas can clear medicine test that enables clinicians to obtain infor- be treated with very high cure rates by standard methods, mation about heart muscle activity. The scan displays the including electrodesiccation and curettage (ED&C), local distribution of a radioactive tracer in the heart. The im- excision, cryosurgery (freezing), and irradiation. ages of the heart are obtained at intervals throughout the See also Cryotherapy. cardiac cycle, and are used to calculate ejection fraction (an important measure of heart performance) and evalu- Resources ate regional myocardial wall motion. BOOKS PERIODICALS Purpose Cook, J. L., and J. B. Perone. “A prospective evaluation of the A MUGA scan may be done while the patient is at incidence of complications associated with Mohs micro- rest and again with stress. The resting study is usually graphic surgery.” Archives of Dermatology 139 (February performed to obtain the ejection fraction of the right and 2003): 143-152. left ventricles, evaluate the left ventricular regional wall Jackson, E. M., and J. Cook. “Mohs micrographic surgery of a motion, assess the effects of cardiotoxic drugs (i.e., papillary eccrine adenoma.” Dermatologic Surgery 28 chemotherapy), and differentiate the cause of shortness of (December 2002): 1168-1172. breath (pulmonary vs. cardiac). Ejection fraction and wall Smeets, N. W., Stavast-Kooy, A. J., Krekels, G. A., Daemen, M. J., and H. A. Neumann. “Adjuvant Cytokeratin Stain- motion are also important measurements made during a ing in Mohs Micrographic Surgery for Basal Cell Carci- stress study, but the stress study is performed primarily to noma.” Dermatologic Surgery 29 (April 2003): 375-377. detect coronary artery disease and evaluate angina. 992 GALE ENCYCLOPEDIA OF SURGERY