EKG

Torsades de Pointes (TdeP)

Ventricular Fibrillation (VF)Rate: CNO as no discernible complexesRhythm: rapid and chaoticP waves: nonePR interval: noneQRS duration: none Note: Fine vs. coarse?

Ventricular Fibrillation (VF)

Ventricular Fibrillation (VF)

…”Next time, try to remove his shirt!”

Asystole (Cardiac Standstill)Rate: noneRhythm: noneP waves: nonePR interval: not measurableQRS duration: absent

AsystoleThe Mother of all Bradycardias

QUESTIONS

AtrioVentricular (AV) Blocks

Atrioventricular (AV) BlocksFirst-degree AV blockSecond-degree AV block, type I(Wenckebach or Mobitz I)Second-degree AV block, type II (Mobitz II)Third-degree AV block (Complete AV Block)

First-degree AV blockRate: depends on underlying rhythm(usually regular)Rhythm: regularP waves: normal in size and shapePR interval: > 0.20 sec but constantQRS duration: < 0.12 sec

First-degree AV block

2nd Degree AV block Type I(Wenckebach/Mobitz Type I)Rate: atrial rate > ventricular rateRhythm: atrial reg.; ventricular irreg.P waves: normal in size and shapePR interval: lengthens with each cycleuntil a P appears with no QRS complexQRS duration: < 0.12 sec (Periodicallydropped QRS complex!)

2nd Degree AV block Type I(Wenckebach/Mobitz Type I)

2nd Degree AV block Type II (Mobitz Type II)Rate: atrial rate > the ventricular rateRhythm: atrial reg.; ventricular irreg.P waves: normal in size and shapePR interval: within normal limits or slightlyprolonged but constantQRS duration: < 0.12 sec (Periodicallydropped QRS complex!)

2nd Degree AV block Type II (Mobitz Type II)

3rd Degree AV block (Complete AV Block)Rate: atrial rate is > ventricular rateRhythm: atrial reg.; ventricular reg. (Pwaves plot through)P waves: normal in size and shapePR interval: no relationship (independent)QRS duration: narrow or wide dependingon location of pacemaker

3rd Degree AV block(Complete AV Block)

Pacemaker Rhythms

Cardiac PacemakersDefinition Delivers artificial stimulus to heart Causes depolarization and contractionUses Bradyarrhythmias Asystole Tachyarrhythmias (overdrive pacing)

Cardiac PacemakersFixed Fires at constant rate Can discharge on T-wave Very rareDemand Senses patient’s rhythm Fires only if no activity sensed after preset interval (escape interval)

Cardiac Pacemakers

Cardiac PacemakersDemand Pacemaker Types Atrial Fires atria Atria fire ventricles Requires intact AV conduction Ventricular Fires ventricles

Cardiac PacemakersDemand Pacemaker Types Atrial Synchronous Senses atria Fires ventricles AV Sequential Two electrodes Fires atria/ventricles in sequence

Cardiac PacemakersSpecial Considerations Pacemaker does NOT affect treatment of cardiac arrest Do NOT defibrillate directly over pacemaker generator Pacemakers may keep AEDs from advising shock

Atrial Pacemaker (Single Chamber)pacemaker •Capture?

Ventricular Pacemaker (Single Chamber)pacemaker

Dual Paced Rhythmpacemaker

Special Notes

S-T ElevationS-T elevation is not significantwithout a 12 lead interpretationShould not be reported!Treat the patient not the monitor

S-T ElevationMonitors filter rhythms and show youwhat they think it shouldST elevation is common on patientswho show no elevation on 12 Lead

Artifact

60 Cycle Interference60 cycle artifact (noise)Problem solve causesElectromagnetic emanations:i.e. TV’s, electric motors, fluorescent lights

60 Cycle Interference

Aberrancy Bundle Branch Block12 Lead ECG required to diagnoseBBB (Left or right BBB?)Describe widened QRS (>0.12 sec)as “aberrant” unless using 12 lead

AberrancyBundle Branch Block

Pulseless Electrical Activity (PEA)The absence of a detectable pulse andblood pressurePresence of electrical activity of the heartas evidenced by ECG rhythm, but not VFor VT + = 0/0 mmHg

Practice Practice PracticeUSE IT OR LOSE IT!!!!



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QUESTIONS?

MEDICAL MATH

MEDICAL MATHAUTHOR REVIEWERS/CONTRIBUTORSTim Dodd AEMCA, ACP Rob Theriault EMCA, RCT(Adv.), CCP(F) Peel Region Base HospitalHamilton Base Hospital Donna L. Smith AEMCA, ACP Hamilton Base Hospital Dan Langevin, PCP (IV) Northeastern Ontario Prehospital Care Program Corey Petrie, ACP Northeastern Ontario Prehospital Care Program Paul Myre, ACP Northeastern Ontario Prehospital Care Program

Learning ObjectivesReview Metric SystemWork with FractionsCalculate ConcentrationsCalculate InjectionsCalculate InfusionsCalculate Weight ConversionParkland Burn Formula

The FEAR FACTOR !!Medical Math holds people back Flattens their learning curveParalyzes the professional from doing their job with confidence

The reality….Medical Math does not have to be this way! Our goal is to change this!

Metric System The metric system must be fully understood to accurately deliver various volumes of fluid and various weights of drugs These are usually given based on the patients weight Basic metric units of measurement are: 1. Length - Meter 2. Volume - Liter 3. Weight - Gram

Basic Metric UnitsMASS VOLUME LIQUIDGRAM CUBIC CENTIMETER MILLILITER G cc ml

Metric System Subdivisions of these basic units are made by moving the decimal point to the left Multiples of the basic units are indicated by moving the decimal point to the right

Metric SystemBased on the Decimal system or multiples of 10• primary unit of weight is the GRAM• smaller unit of weight is the MILLIGRAM• larger unit of weight is the KILOGRAM 1 GRAM is equal to 1,000 MILLIGRAMS 1 KILOGRAM is equal to 1,000 GRAMS