(Forensic Medicine Fundamentals and Perspectives).0012

DEMO : Purchase from www.A-PDF.com to remove the watermarkElectricity, Lightning, and Gases 13Case Study Domestic accidents involving electricity, as wellThe lifeless, fully clothed body of a as other types of accident involving power lines,78-year-old female was found in the mid- the use of electricity with suicidal intent, anddle of winter by the mobile nursing service high voltage are seen in medical forensic prac-on the bathroom floor of the apartment in tice. Electricity is rarely used with homicidalan old building where the victim lived intent. Knowledge about the effects of electricityalone. The bathtub had been filled with has been gained from its use in executions (thewater; next to it lays an intact, connected “electric chair”). Electricity is also used as ahairdryer, while an old oil heater stood at weapon to incapacitate an individual for the pur-the side of the room. The emergency physi- poses of detainment (the Taser gun).cian called to the scene confirmed death(bright red livor mortis, advanced rigor Death by electrocution is primarily acciden-mortis), detected a pacemaker subcutane- tal or work-related; it is occasionally seen in aously beneath the left clavicula, and found homicidal context (sometimes falsely inter-several packs of medication, some opened, preted as alleged accidental or suicidal death). Insome empty: diazepam, a β-blocker, an the case of suicide (e.g., hairdryer in the bath-antidepressant, as well as antithrombosis tub) and accidental death resulting from auto-stockings. The victim’s nail beds were also erotic activity, live conductors (cables) arebright red, and an old, healed scar running attached to the genital or anal region, for exam-lengthways along the sternum suggested ple, or to the extremities. Incorrectly installedprevious cardiac bypass surgery. Since no electrical devices and cables or poorly main-further medical intervention was called for, tained devices can cause death; in such cases,and once external examination was com- charges of manslaughter are often broughtplete, the emergency physician filled out all against the responsible party. Moreover, evi-the necessary forms, giving the cause of dence of a fatal electrical accident is relevant indeath as unclear. The subsequent police terms of insurance law. Individuals with someinvestigation, as part of which a forensic knowledge of electricity have been known to useautopsy was performed, concluded the it as a means to commit suicide. Fatal injury duecause of death to be carbon monoxide poi- to mobile phones exploding—a rare phenome-soning (COHb = 32 %). A technical expert non seen mainly in Asia—has been reported; thelater determined the oil heater to be cause here is believed to be the use of cheap bat-defective. teries, possibly in combination with extreme heat. Electric cushions and blankets, e.g., in a child’s bed, can cause burns.R.B. Dettmeyer et al., Forensic Medicine, 213DOI 10.1007/978-3-642-38818-7_13, © Springer-Verlag Berlin Heidelberg 2014

214 13 Electricity, Lightning, and Gases13.1 Fatal Electrocution control is lost, the conducting object can no lon- ger be actively released, and the current contin-Contact with current-carrying conductors can ues to flow through the body. The “let-go”have various effects on the body: threshold is exceeded beyond 15 mA, the risk of• Electrical injury due to electrical stimulation: fatal cardiac arrhythmia is increased from 50 mA, and values >80 mA cause loss of consciousness Muscles, nerves, and the cardiac conduction and ventricular fibrillation. system• Electrothermal injury due to local current- The alternating current usually found in induced heat damage, e.g., local charring or households has a frequency of 50 Hz. The likeli- cutaneous metallization hood that a current alternating direction 50• Indirect injury, e.g., fall injuries following times/s triggers fatal cardiac arrhythmia (by electrocution reaching the heart during the vulnerable phase) is In practice, a distinction is made between four significantly higher compared to the effects ofvoltage ranges: extra-low, low, high, and extra- direct current. Very high-frequency currents,high voltage. Household voltage is usually 220 V however, penetrate the organism only slightly,(USA, 110 V) with a frequency of 50 Hz (USA, while the thermal effects at the interface to the60 Hz). The low-voltage range goes up to 600 V, current-carrying conductor or electrode arewhile the high-voltage range is between 600 and greater. For this reason, high-frequency surgery1,000 V and higher. is carried out in the 300- to 2,000-kHz range. However, the duration of current flow (contact Frequencies over 100,000 Hz are harmless, sincetime) and the strength of current passing through nerves are no longer excited; at even higher fre-the body are the crucial factors in electrical quencies, the current runs off body layers close toinjury. The current (I) is determined by the volt- the surface and internal body structures remainage (U) and the body’s resistance (R) according unaffected.to Ohm’s law ((U = R × I). If the hand comes incontact with a current-carrying conductor, mild The effects of current strength and voltage onmuscle contraction will ensue at a current of the heart are shown in Table 13.1.1 mA; from 5 mA, the lower arm will be affected;up to 15 mA it is still possible to break contact, Skin resistance determines current strength inwhich is no longer the case from 25 mA. Currents the body, whereby a distinction is made betweenof between 25 and 80 mA cause a rise in blood various alternating-current ranges (Table 13.2).pressure and possibly also cardiac arrhythmias. Alternating-current frequencies between 40 and Skin resistance at the current entry and exit 150 Hz are hazardous. Ventricular fibrillation ispoints can vary depending on corneal thickness, generally the cause of death in electrical acci-skin moisture (reduced resistance due to perspi- dents. The risk of fatality is greater when the cur-ration!), or protective clothing: gum boots serve a rent path between contact sites goes via the heartprotective function, while walking barefoot on (arm–arm or arm–foot). However, the directionwet ground is particularly hazardous. In individ- of the current is also relevant; in the case of aual cases, the question of injury or fatal cardiac transverse current flowing from hand to hand, aarrhythmia (generally ventricular fibrillation) lower proportion of the current flows through thedepends on several factors. In addition to the cur- heart compared with a longitudinal current flow.rent itself, its path and duration, the level of skin Current flow to other sites, such as between tworesistance, and the age of the victim, the crucial fingers, usually only causes local thermal injury.factor in electrocution is the point in time of thecurrent surge in relation to the vulnerable cardiac Electrical Burns. In the case of electrical fatali-phase. The “let-go current” is also a crucial fac- ties, electrical burns at the point of contact withtor: firstly, the current excites nerves causing sus- the conductor need to be sought on the body.tained muscle contraction. Once local muscle Points of contact can be extremely small, unchar- acteristic in appearance, or completely absent. Broad and moist contact surfaces in particular often develop no electrical burns at all. If electrical

13.1 Fatal Electrocution 215Table 13.1 The effects of current strength and voltage on the heartCurrent strength Voltage Effects on the heart in particular<25 mA Up to 65 V Extra-low voltage, harmless<25 mA 100–130 V Low voltage: electrical effect; short muscle cramps, no injury25–80 mA 110–380 V (usual domestic Low voltage: electrical effect; brief asystole and arrhythmia or alternating current) (reversible) ventricular fibrillation, potentially life-threatening80 mA–8 A 110–380 V Low voltage: electrical effect; ventricular fibrillation (reversible), potentially life-threatening>8 A 2,000–3,000 V (up to High voltage: electrothermal burns and acute asystole 100,000 V)>8 A >100,000 V Extra-high voltage: severe electrothermal burns (temperature up to 4,000 °C), charring, acute asystole; current transfer possible even in the absence of contact with the conductor (“electric arc”)Table 13.2 The effects of Amperage Effectalternating current <0.5 mA From 0.5 mA Perceptible with the tongue at most From ca. 5 mA Perceptible tingling From ca. 15 mA Muscle excitation Muscle cramps, flexion contractions, no longer 25–50 mA possible to let go of the contact site independently Cardiac arrhythmia, possible loss of consciousness in Ca. 50–80 mA the case of longer contact times From 80 mA Risk of acute ventricular fibrillation Short contact times are sufficient for ventricular From ca. 3 A fibrillation; respiratory arrest due to respiratory muscle paralysis Electrothermal effect with tissue charring at the contact site Note: In the case of direct current, limit values can be increased by a factor or fourburns are present, the following findings of elec- there is microscopic evidence of a cellular reac-trothermal injury are usually made: tion and/or local hemorrhage. From a differential• Crater-like elevation of the skin around a cen- diagnostic point of view, it may be necessary in individual cases to distinguish between a burn tral depression (sunken center) (Fig. 13.1). mark (contact burn) and an electrical burn. One• Pale, porcelain-like, or alabaster-colored important criterion here is the formation of an elevated border, as well as possible discoloration borders. at the center of the lesion (Fig. 13.3).• Particles of metal from the conductor may be Depending on the intensity of the local “burnt into” the skin (so-called metallization), current, blackish charred contact sites can be although this is not always the case. Metal seen on the skin, frequently on the fingers, and particles can be detected with the help of spec- involving metallization that is often only detect- trographic or histochemical analysis. able using microscopic analysis (Fig. 13.4).• Blister formation in the raised border of the However, additional skin samples taken adja- electrical burn (honeycomb pattern) can be cent to the affected area should also be investi- seen histologically. gated, since metal particles (e.g., copper) in the• Fishbone-like deformation of epidermal basal skin of electricians’ hands, for example, are cells and nuclear elongation can also be found relatively often even in the absence of detected histologically (Fig. 13.2). electrocution. Although electrical burns are often specific forelectrocution, they are not a sign of vitality unless

216 13 Electricity, Lightning, and GasesFig. 13.1 Electrical burn. Trough-like electrical burn on Alongside electrical fatalities in the context ofthe palm of the hand with multiple sunken areas occupational accidents (subject to reporting requirements), electrocution in the bath meritsFig. 13.2 Histological finding in an electrical burn: basal particular attention in forensic medical practice.cell deformation, elongation, as well as palisade andfishbone-like arrangement of cell nuclei Electrocution in the Bath. Occasionally, a fine linear reddening of the skin can be seen at the level of the water in the case of electrocution in the bath (Fig. 13.5). Even in the absence of any findings, a fatality in the bath should always arouse the suspicion of electrocution. Since electrical burns can be incurred post-mortem, they do not represent a sign of vitality. Thus the diagnosis “electrocu- tion” is often a diagnosis of exclusion. In equivo- cal cases, a technical expert needs to be consulted, not least to prevent further cases of electrocution. Acute asystole may occur up to some minutes following contact with a current. Even when electrocution is initially survived, electrothermal injury to the skeletal and heart muscles (infarct- like pattern of damage) can cause late fatalities in the setting of multiorgan failure (MOF), includ- ing kidney failure (“crush kidneys”). Whenever an individual is found lifeless in a filled or unfilled bathtub, particular attention should be paid to finding and identifying an electrical burn. Suspicious skin lesions should be investigated histologically. All conductors and current sources at the scene need to undergo technical inspection, while a careful record of the scene itself needs to be made. Cases are known where bodies have been “cooked” in the bathtub due to bathwater being heated by a hairdryer falling into the water. When the diagnosis “death by electrocution” appears plausible only as a diagnosis of exclu- sion, the goal of any criminal investigation is to establish whether an accident, a suicide, or a homicide has taken place. In forensic medical practice, electrocution is usually accidental in nature; electricity is rarely used to commit sui- cide. It is essential to weigh up findings carefully while taking the background history, findings at the scene of death, as well as autopsy results into consideration. This may provide information about tetanic muscle cramps or a hand “getting stuck” on a conductor. Emitting a sudden scream followed by loss of consciousness and pulse is consistent with electrocution. Finding a body in

13.1 Fatal Electrocution 217Fig. 13.3 Differential contact electricaldiagnosis between a burn burn burnmark (contact burn) and anelectrical burn: skin burnmark without a raised border,electrical skin burn with araised borderFig. 13.4 Blackish charredelectrical contact site on theskin of the fingerFig. 13.5 Fine linearreddening of the skin at thelevel of the water in the caseof electrocution in the baththe vicinity of a power source should suggest the several decimeters from a 100,000-V conductor.possibility of electrocution. An electric arc with high current, extreme heat, and intense light is formed between the conduc- High-Voltage Accidents. In the case of high tor and the body. Victims show charring on thevoltage, no direct contact is needed for current to conducting extremities and convulsive contortionpass through the body—being at a certain dis- of the facial muscles; eyelids may also be closed.tance from the conductor is sufficient, e.g., a few When there is no electric arc and flashovercentimeters from a 10,000-V conductor and

218 13 Electricity, Lightning, and Gasesoccurs, multiple brownish-blackish, densely Fig. 13.6 High-voltage accident with facial burns.arranged skin perforations can be seen. Protrusion of the tongue and singed hair Most high-voltage accidents occur in an occu- ily a sign of vitality in high-voltage accidents,pational setting, almost always affecting males since electrically induced muscle contraction(working on overhead power lines, substations, can also cause increased skinfold formation.transformers, and tall cranes that come into con- 3. Scalp hair, eyebrows, eyelashes, and facialtact with high-voltage current, etc.). Brief con- hair are often singed.tact with a current is often followed by a fall and 4. Depending on the duration of current flow,associated fall injuries, which are sometimes both direct and indirect burn injurieserroneously interpreted as the cause of death. In (Fig. 13.7) including extensive charring, artic-the majority of cases, high-voltage accidents ular dehiscence, and an “overcooked” appear-cause immediate death—direct contact with a ance of skeletal muscles have also beenpower line is not necessary for this to occur, described.since an electric arc can be formed from an elec- 5. An electric arc can cause “molten beads” totric arc flashover. Temperatures within electric form on bone from molten calcium phosphate.arcs of this kind reach several thousand degrees 6. In addition, petechial hemorrhage of the con-Celsius. Such cases are usually accidental, where junctiva, facial skin, mucosa of the upperthe victim came too close to high-voltage power respiratory tract, as well as beneath the pleuralines. The flashover distance for 100 kV is and epicardium, are occasionally seen. Theseapproximately 3.5 cm, increasing with increas- findings are suggestive of current-induceding voltage. Contact may also be caused, for tetanic respiratory muscle contraction and anexample, by urinating from a bridge onto high- intrathoracic pressure increase (“electricalvoltage power lines. Suicide should be consid- asphyxia”).ered in individual cases (climbing up a Extensive skin burns running lengthways overhigh-voltage mast). Although most high-voltage the body are seen in electrical arc accidents, theaccidents produce clear findings on the body andclothing, short but intense contact with a high-voltage conductor has been known to cause fatal-ities with only scant findings. A small electricalburn, as seen in low-voltage accidents, is oftenthe only finding, and even this may be overlookedif localized on feet covered by shoes. However,high-voltage accidents generally produce the fol-lowing classic constellation of findings, theintensity of which depends on the duration ofcurrent flow:1. Mostly third-degree burns to the face and other exposed sites (Fig. 13.6). The formation of “crow’s feet” (see Fig. 12.8) is possible, i.e., lines of spared skin at the canthi of the eyes in otherwise burned facial skin. Other lines of skin spared from burning suggest a final contraction of the facial mimic muscles. Linear sparing of this kind is also interpreted as a sign of vitality in high-voltage and elec- tric arc accidents.2. Possible metallization along skinfolds similar to “crow’s feet.” This finding is not necessar-

13.2 Lightning 219 burns sometimes ending abruptly where they meet insulating clothing, e.g., sparing of the skin of the foot if shoes are worn (Fig. 13.8). In high-voltage accidents, damage to cloth- ing needs to be correlated with findings on the body. Clothing can be badly torn (Fig. 13.9) and charred black, while particles of molten metal may be detected. Damage to clothing and shoes may help to identify the current entry point. The feet or soles are the most commonly seen point of current exit, demonstrating extensive or patchy charring of the skin (Fig. 13.10). 13.2 LightningFig. 13.7 Extensive blackish charring of the skin and Although rare, lightning-related accidents occursubcutaneous soft tissue at the point of current entry on and are associated with a mortality rate of up tothe knee 40 % in cases of extremely high voltage delivered within less than a millionth of a second. A light- ning discharge can carry a current of several mil- lion volts. Fluid in moist objects vaporizes along the lightning pathway, while mechanical and thermal injury can occur.Fig. 13.8 Shoes spare thefeet from burning in the caseof an electric arc accident

220 13 Electricity, Lightning, and GasesFig. 13.9 Badly torn andpartially blood-soakedclothing following ahigh-voltage accidentinvolving an electric arcFig. 13.10 Patchy blackish charring at the point of cur- • Flash discharge: A lightning bolt “jumps”rent exit on the skin of the foot sole from one object to another. Lightning-Induced Injury. The mechanisms • Contact strike: The victim comes in contactby which a bolt of lightning may cause injury are with an object hit by lightning.differentiated as follows:• Direct stroke. • Blunt trauma: Secondary injury, e.g., a victim• Step voltage: A lightning bolt initially strikes falls as a result of a bolt of lightning. As with high-voltage accidents, findings on the ground or possibly a tree. the body and clothing should be identified and compared. Fernlike Injury. Fernlike injury (arborescent erythema or feathering burns; Fig. 13.11), which forms part of the injury pattern typically seen in lightning strikes, is due to small-vessel hyperemia in the corium and can disappear within hours post-mortem and with increasing postmortem interval. In addition, epidermal cells in an elon- gated and palisade-like arrangement can some- times be seen at the same level. Singed hair along the lightning pathway, charred and torn clothing, metal particles with signs of melting, as well as torn shoes are also observed. The entry point of lightning in the case of fatality is typically located on the head (crown area). Although not always the case, extensive linear skin burns may be observed along the trunk and on the lower extrem- ities. Contact burns and metallization may occur wherever the skin comes in contact with metal objects. Clothing is subject to varying degrees of mechanical and thermal damage, including hole formation and melting of metal parts (belt buck- les, wristwatches, earrings, buttons, etc.). As in high-voltage accidents, holes and tearing may be seen in footwear (shoes, socks/stocking).

13.3 Electric Shock Devices and Taser Guns (Stun Guns and Remote Electrical Discharge Weapons) 221 abFig. 13.11 (a, b) Two cases with fernlike injury in lightning strikes Ground Strike. The term “ground strike” or 13.3 Electric Shock Devices“step voltage” describes the partial flow of cur- and Taser Guns (Stun Gunsrent from a lightning bolt through the body (from and Remote Electricalleg to leg) of an individual or animal located near Discharge Weapons)the point at which a lightning bolt strikes theground. Ground strikes of this kind form a dis- Electric Shock Devices. Electric shock devicescharge voltage pattern, whereby voltage reduces are gun- or prod-like devices designed to inca-as it moves out from the center towards the pacitate a subject by means of an electrical dis-periphery. Thus when the legs are in a striding charge—without causing significant injury.position, the potential difference on the ground When pressed against the skin, the high-voltagemay be picked up (“stride potential”) and cause circuit is reduced by skin resistance to the extentdeath. In this way, bolts of lightning are able to that the current at the electrodes drops signifi-kill entire herds of cattle. cantly. Commercially available devices produce an unpleasant perception of pain without impair- Although immediate resuscitation following ing consciousness. Skin reddening (erythema) ina lightning strike may be successful, the extent a paired arrangement, approximately 5 mm inof burns as well as injury to internal organs will diameter and at intervals corresponding to thedetermine the further course. Neurological defi- distance between the electrodes, are possible;cits of varying degree and duration dominate local pain has been reported. Local erythema isthe clinical picture in the case of survival. In temporary and fades within several hours. Theaddition to acute cardiac and cerebral death fol- paired arrangement of erythema is the most sig-lowing a lightning strike, myocardial necrosis nificant indication of the use of an electric shockor fulminant bronchopneumonia may lead to device.late fatality despite initially successful resusci-tation. Acute kidney failure may develop The Taser Gun. “Taser” is an acronym ofdepending on the degree of tissue injury. “Thomas A. Swift’s electric rifle” from the bookSurvivors of lightning strikes often demonstrate by V. Appleton (1911). In contrast to electricneurological deficits, including aphasia, tempo- shock devices, two projectiles (Taser darts) arerary blindness, swallowing and speech impair- fired out of a cartridge from long range and at aments, spastic paraplegia affecting the legs, speed of up to 50 m/s. The darts are fitted withcerebellar injury that is reversible for up to insulated wires that deliver electrical impulses1 year following the insult, as well as temporary from the Taser gun to the subject. The wires areparalysis. several meters long, while the darts have small

222 13 Electricity, Lightning, and Gasesbarbs capable of penetrating several layers of increasing number of reported fatalities associ-clothing. The device has a range of up to 10 m. ated with the use of Taser guns. The recommen-Although each cartridge can only be fired once, dation that police officials keep a defibrillatorthe operator is able to deliver several electric ready for use when deploying Taser guns hasshocks to a subject by pressing the trigger. Taser been discussed. However, from a critical point ofguns are considered appropriate weapons for use view, it must be borne in mind that a proportionat an escalation level below that of firearms and of the subjects to be apprehended—as we knoware supposed to confer a lower risk of mortality. from experiences with so-called positionalAt the same time, Taser guns are used by police asphyxia during or following police apprehen-officials as a means of self-defense. They should sion—are in a psychologically disturbed state,only be used when all other means (physical highly agitated due to psychiatric disease (schizo-force, baton, pepper spray) have proved unsuc- phrenia, psychosis, delusions, etc.), and/or undercessful; moreover, the subject should be given the influence of alcohol or drugs. Long-termprior warning of their use. In practice, the effects abusers of neuroleptics as well as numerous typesof the gun depend on various factors: of drugs (in particular cocaine, amphetamines,• The point at which the electrodes penetrate the heroin) may have occult cardiac damage that pre- disposes them to sudden fatal ventricular fibrilla- body tion triggered by the electric shock delivered by a• The distance of the electrodes from one Taser gun. An inflammatory cardiac response is not impossible, whether due to chronic infection, another e.g., hepatitis, or due to an often undetected yet• The length of the current path between the acute viral infection with mild cardiac involve- ment, which would normally follow an unre- electrodes markable and often symptom-free course before• The nerves and muscles affected by the cur- resolving. Given the known risk of preexisting cardiac damage in drug abusers and individuals rent path (is the heart affected?) with psychiatric disease, it is to be expected that• The penetration depth of the electrodes the wider availability and use of Taser guns will• The current intensity delivered (should be 3 A, be accompanied by a corresponding increase in related fatalities. Precisely for this reason, police but can go up to 5 A) officials in some countries are obliged to sum- According to the manufacturers of the Taser mon emergency medical services to examine vic-gun, which can fire two or four barbed darts, an tims following deployment of Taser guns. Thereelectric shock of approximately 17,500– is also a regulation specifying that Taser darts500,000 V (open-circuit voltage) is delivered via should only be removed from the body of the vic-the barbed hooks attached to the wires only when tim by a physician.the trigger is activated or for up to 5 s. The cur-rent surge delivered by the Taser gun causes In many countries where Taser guns are inimmediate loss of neuromuscular control, i.e., the use, particularly in the USA, detailed forensicsubject is immediately incapacitated or defense- investigations or autopsies are only rarely per-less and can be apprehended by police officials. formed in the case of Taser-related deaths. FromThe Taser gun is now available worldwide and a forensic point of view, investigations arehas been in use by British and US police authori- required and should include microscopic analysisties since 2001. Although the immediate electric of the heart and cardiac conduction system. Ofshock causes brief, intense pain, local skin find- 167 individuals who died following the use ofings at the point of impact of the live mini-darts Taser guns between 1999 and 2005, coronersshow scant morphological changes. stated that Taser deployment was the cause of From a medical perspective, however, the death, contributed to death, or could not beelectric shocks delivered in this context are not excluded as the cause of death in 27 cases (fromentirely without hazard. In principle, electricshocks of this kind may trigger fatal ventricularfibrillation if delivered during the vulnerablephase of the cardiac cycle. Thus, there are an

13.4 Gas Fatalities 223a report by “Arizona Republic,” http://www. Other gases, such as hydrogen sulfide and putre-raidh.org/RAIDH-devoile-la-liste-des-167.html). faction gases, are found in sewage plants andSince June 2001, Amnesty International has silos, among others.reported more than 330 fatalities associated withTaser deployment in the USA alone. In more than Carbon Monoxide Intoxication. Carbon mon-50 cases, coroners maintained that the electric oxide has a 300-fold greater affinity for hemo-shocks were the direct or indirect cause of death. globin than oxygen; as a result, the latter isIn many cases, alone the proximity in time of displaced. Thus even small ambient concentra-death to the use of a Taser gun suggests a causal tions are enough to cause fatal intoxication.link. For this reason, Taser guns should be classi- While COHb values of around 15 % are possiblefied at best as “less lethal weapons” than fire- in heavy smokers, COHb values above 40 % arearms. Particular caution should potentially be considered a plausible cause of death. Valuesexercised when using Taser guns in the vicinity <40 % combined with a fatal course are sugges-of flammable materials or fumes, such as gaso- tive of preexisting (cardiac) damage to theline fumes. organism or additional intoxication with a poi- son such as cyanide. The most commonly seen In turn, evidence that the use of Taser guns causes include house fires, defective gas pipes,results in fewer fatalities than the use of conven- smoldering fires, or poor room ventilation.tional firearms has hitherto been unconvincing. Suicides are occasionally seen involving theIf anything, there are fears that the purported diversion of car fumes into the interior of a carharmlessness of the Taser gun has encouraged or into a closed garage, resulting in fatal carbonits premature and unnecessary deployment. monoxide intoxication. On external forensicThere is criticism that Taser guns are used in examination, bright red livor mortis (Fig. 13.12)situations where a firearm or even a baton would and pinkish finger- and toenails are conspicuous,not have been warranted. In many countries, the while salmon-colored muscles and cherry-redTaser gun has not yet been classified according blood are apparent at autopsy. Internal organsto firearm regulations or remains the subject of may also show a striking bright reddish color. Itcontroversy. However, it is conceivable that in is always essential to find the source of carboncountries with relatively high numbers of fire- monoxide; where necessary, a technical expertarm deaths (approximately 30,000/year in the should be consulted.USA), consistently substituting a firearm with aTaser gun indeed results in an overall reduction Decomposition and Fermentation Gases. Inin fatalities. addition to carbon monoxide poisoning, intoxi- cation by gases that are heavier than oxygen— The potential use of Taser guns as a method of and thus settle and accumulate at the bottom oftorture is cause for concern, given that intense structures such as silos, septic tanks, and diges-pain can be inflicted in a traceless manner (so- tion towers—is also possible. Without the victimcalled white torture). The UN Committee Against subjectively perceiving any symptoms, anoxicTorture expressed its concern in this regard in asphyxiation due to lack of oxygen as well asNovember 2007. Also of concern is the use of sudden loss of consciousness may ensue. This isTaser guns by laypersons for self-defense pur- caused by so-called fermentation gases, whichposes or their misuse as a means of intimidation have a significantly higher carbon dioxide (CO2)to compel sexual activity, for example. content than normal ambient air, which is usu- ally around 0.04 %. CO2 is formed during the13.4 Gas Fatalities alcohol fermentation of mash, must, and feed- ing stuffs. Decomposition gases can build up atGas fatalities are classified as death by asphyxia. the bottom of silos and in wine cellars. Odorless,Carbon monoxide (CO) intoxication is the most the gas goes undetected. The risk of symptomscommonly encountered accident involving gas. and a fatal course increase according to the con- centration of CO2 in ambient air (Table 13.3).

224 13 Electricity, Lightning, and GasesFig. 13.12 Bright red livormortis in the partially charredbody of a domesticsmoldering fire victim(COHb level in postmortemblood, 52 %)Table 13.3 CO2 concentrations in ambient air and their In addition to its destructive force, fire alsoeffects produces fumes; in addition to carbon monoxide, these fumes often contain other elements in vary-CO2 content (%) Effect ing concentrations, such as aldehydes, acrolein,0.5 cyanides, sulfur dioxide, ammonia, hydrogen1 Maximum workplace chloride, and phosgene. The concentrations of4 concentration individual elements of smoke depend largely on the type of material burnt. In cases of fatality,9 Symptoms apparent after several samples should be taken from each pulmonary14 hours lobe and stored in headspace vials for the toxico-20 logical detection of volatile gases. Increased respiratory frequency, impaired concentration, cardiac Caisson Disease (Decompression Sickness). symptoms, reduced vigilance, The air we breathe is made up of 78 % nitrogen drowsiness (N), 22 % oxygen (O2), and 1 % other gases. All gases dissolve in blood and tissue. Once oxygen Fatal within 5–10 min, faster in the has been used up, mainly nitrogen remains in case of preexisting cardiac damage blood and tissue. Just like oxygen dissolved in blood, nitrogen dissolved in blood can also be Sufficient to extinguish a candle released and form bubbles at depths of around flame 13 m. The deeper the diving depth, the more nitrogen is released with each breath due to water Rapid death pressure. Depending on the temperature and water pressure, blood and tissue absorb nitrogen;Thus, unprotected individuals attempting to the maximum absorbable volume is referred to ashelp already unconscious victims occasionally the saturation limit, which is reached after a cer-become victims of asphyxia themselves. tain length of time at particular depths. As pres- sure reduces while the diver’s return to the There is a danger that individuals entering a surface, the “stored” nitrogen is delivered to theroom where there is an increased level of CO2 lungs via the bloodstream. In order for the nitro-will initially feel a sensation of mild intoxication; gen to be safely expelled from the lungs, particu-however, victims rapidly collapse and lose con- lar ascent rates need to be observed. Failure tosciousness, exposing the respiratory organs toeven greater levels of fermentation gases due tothe higher concentrations of CO2 at ground leveland thereby increasing the gas’ noxious effects.Since silos need to be entered by a ladder, theyoften present the additional hazard that, on losingconsciousness, the victim falls from the ladderinto the silo.

Selected References and Further Reading 225adhere to decompression times, combined with Carte AE, Anderson RB, Cooper MA (2002) A largerapid ascent, leads to the formation of nitrogen group of children struck by lightning. Ann Emerg Medbubbles in blood and tissue (caisson disease), 39:665–670causing damage to small blood vessels andtissue. Cherington M, Yarnell P, Hallmark D (1993) MRI in lightning encephalopathy. Neurology 43:1437–1438 Caisson disease, which has varying degrees ofseverity, is not seen at depths of less than 9 m. Dawes DM, Ho JD, Reardon RF et al (2010) The respira-Early symptoms may appear within minutes or tory, metabolic, and neuroendocrine effects of a newafter several hours, with the spectrum ranging generation electronic control device. Forensic Sci Intfrom pruritus to death and including skin irri- 207:55–60tation (formication); fatigue; exhaustion; backpain; joint and extremity pain; sensory, visual, Dennis AJ, Valentino DJ, Walter RJ (2008) Taser26 dis-and auditory impairment; speech disorders; and charges in swine produce potentially fatal ventricularparalysis. In extreme cases, embolic spread of arrhythmias. Acad Emerg Med 15:66–73nitrogen bubbles can cause fatal pulmonary arteryembolism. At autopsy, attention should be paid to Dumas JL, Walker N (1992) Bilateral scapular fracturesidentifying gas bubbles in the capillaries and fatty secondary to electrical shock. Arch Orthop Traumatissue, in addition to cardiac, pulmonary, and Surg 111:287–288cerebral gas embolism. Osteoarthropathies rep-resent the most common late effect in survivors El Faki HMA (1993) High voltage electrical injuries—of caisson disease. However, fatalities associated clinical and operative observations. Eur J Plast Surgwith caisson disease are rare among divers, with 16:89–93drowning representing a more frequent cause ofdeath, sometimes due to claustrophobia or panic Fieseler S, Zinka B, Peschel O, Kunz SN (2011)reactions. Electroweapon Taser®. Function, effects, critical aspects. Rechtsmedizin 21:535–540Selected References and FurtherReading Fontanarosa PB (1993) Electrical shock and lightning strike. Ann Emerg Med 22:378–387Al-Jarabah M, Coulston J, Hewin D (2008) Pharyngeal perforation secondary to electrical shock from a Taser Han JS, Chopra A, Carr D (2009) Ophthalmic injuries gun. Emerg Med J 25:378 from a Taser. CJEM 11:90–93Amnesty International: USA (2008) “Less than lethal?” Ho JD, Dawes DM, Reardon RF et al (2011) Human car- The use of stun weapons in US law enforcement. http:// diovascular effects of a new generation conducted www.amnesty.org/en/library/asset/AMR51/010/2008/ electrical weapons. Forensic Sci Int 204:50–57 en/530be6d6-437e-4c77-851b-9e581197ccf6/amr 510102008en.pdf Jauchem JR (2011) Increased hematocrit after application of conducted energy weapons (including TaserAndrews C, Cooper MA, Holle R (2009) Section V: devices) to Sus scrofa. J Forensic Sci 56:229–233 Electrical injuries by source of electricity of mecha- nism of injury. In: Fish RM, Gedes LA (eds) Electrical Jauchem JR, Sherry CJ, Findes DA, Cook MC (2006) injuries: medical and bioengineering aspects, 2nd edn. Acidosis, lactate, electrolytes, muscle enzymes and Lawyers & Judge Publishing Company, Tucson, other factors in blood of Sus scrofa following repeated pp 373–397 Taser exposures. Forensic Sci Int 161:20–30Augustin AJ, Koch F, Böker T (1995) Macular damage Kornblum RN, Reddy SK (1990) Effects of Taser in fatalities following lightning strikes. Ger J Ophthalmol 7: involving police confrontation. J Forensic Sci 434–448 214–216 Kroll M (2009) Physiology and pathology of Taser elec-Biro Z, Pamer Z (1994) Electrical cataract and optic neu- tronic control devices. J Forensic Leg Med 16:173–177 ropathy. Int Ophthalmol 18:43–47 Le Blanc-Louvry I, Gricourt C, Touré E, Papin F, Proust BBozeman WP, Hauda WE, Heck JJ et al (2009) Safety and (2012) A brain penetration after Taser injury: contro- injury profile of conducted electrical weapons used by versies regarding Taser gun safety. Forensic Sci Int law enforcement officers against criminal suspects. 221:e7–e11 Ann Emerg Med 53:480–489 Lichtenberg R, Dries D, Ward K, Mashall W, Scanlon P (1993) Cardiovascular effects of lightning strikes. J Am Coll Cardiol 21:531–536 Lifschultz BD, Donoghue ER (1993) Deaths caused by lightning. J Forensic Sci 38:353–358 Mangus BE, Shen LY, Helmer SD, Maher J, Smith RS (2008) Taser and Taser associated injuries: a case series. Am Surg 74:862–865 Mellen PF, Weedn VW, Kao G (1992) Electrocution: a review of 155 cases with emphasis on human frac- tures. J Forensic Sci 37:1016–1022 Milzman DP, Moskowith L, Hardel M (1999) Lightning strikes at a mass gathering. South Med J 92:708–710 Mueller B (1975) Gerichtliche Medizin, 2nd edn. Springer, Berlin/Heidelberg/New York Nafs FJE, Aromir FC, Carreira IS, Olaso PSC (1993) High tension electrical burns. Eur J Plast Surg 16:84–88

226 13 Electricity, Lightning, and GasesNg W, Chehade M (2005) Taser penetrating ocular injury. Zack F, Rummel J, Püschel K (2009) Blitzschläge Am J Ophthalmol 139:713–715 auf Fußballplätzen – Eine unterschätzte Gefahr. Rechtsmedizin 19:77–82Sloane CM, Chan TC, Vilke GM (2008) Thoracic spine compression fracture after TASER activation. J Emerg Zack F, Rammelsberg JO, Graf B, Büttner A (2010) Tod Med 34:283–285 durch Bltizschlag – und wieder unter einem Baum. Rechtsmedizin 20:108–110Sousa W, Ready J, Ault M (2010) The impact of Taser on police use-of-force decisions: findings from a random- Zack F, Raphael T, Kupfer J, Jokuszies A, Vogt PM, ized field-training experiment. J Exp Criminol 6: Büttner A, Püschel K, Schalke B, Todt M, Dettmeyer 35–55 R (2013) Four fatalities due to a lightning on a golf course. Rechtsmedizin 23:114–118Tropea BI, Lee RC (1992) Thermal injury kinetics in elec- trical trauma. J Biomech Eng 114:241–250 Zaffren K, Durrer B, Henry JP, Brugger H (2005) Lightning injuries: prevention and on-site treatment inWetli CW (1996) Keraunopathology. An analysis of 45 mountains and remote areas: official guidelines of the fatalities. Am J Forensic Med Pathol 17:89–98 International Commission for Mountain Emergency Medicine and the Medical Commission of theZack F, Hammer U, Klett I, Wegener R (1997) Myocardial International Mountaineering and Climbing Federation injury due to lightning. Int J Leg Med 110:326–328 (ICAR and UIAA MEDCOM). Resuscitation 65: 269–372Zack F, Rothschild MA, Wegener R (2007) Blitzunfall – Energieübertragungsmechanismen und medizinische Folgen. Dtsch Ärztebl 104:A3545–A3549