Downloaded 118 times
Uploaded bySaikumar Dunga
Defibrilllation
Defibrillation is a process that delivers an electric shock to stop an irregular heartbeat and restore normal rhythm. Early defibrillation within the first few minutes of cardiac arrest is crucial for survival. Pioneers like Claude Beck developed the defibrillator and helped revive heart attack victims. Proper defibrillator use requires correct pad placement and force, as well as ensuring safety from fires and electrical hazards. The delivery of the shock must be coordinated to avoid potential dangers and maximize effectiveness.
More Related Content
Similar to Defibrilllation
Defibrilllation
- 1.
- 2. Cardiac Arrest Algorithm D– danger R – response S – shout A B C – – – airway breathing circulation D – defibrillation
- 3. DEFIBRILLATION • Defibrillation isa process in which an electronic device sends an electric shock to the heart to stop an extremely rapid, irregular heartbeat, and restore the normal heart rhythm.
- 4. Importance of Early Defibrillation •To give actions cardiac the victim the best chance must occur within the first arrest: of survival, 3 moments of a 1) 2) 3) Activation of the emergency medical services Provision of CPR Operation of a defibrillator AHA guidelines 2010.Section 6.Electrical therapies
- 5.
- 6. • Claude Beck(1894-1971) was a pioneer of heart surgery,. He also developed ways to revive heart attack victims, including the defibrillator and CPR • In 1947, Beck successfully defibrillated his first patient, a 14-year-old boy whose heart went into fibrillation after an operation. • The defibrillator used on this patient was made by James Rand, a friend of Beck. It had silver paddles (the size of large tablespoons) that were used in open-chest situations..
- 7. • Nine yearslater (1956) Paul Zoll used a more powerful unit to perform the first closed-chest defibrillation. • In Belfast , ambulance-transported physicians first achieved pre-hospital defibrillation in 1966. Defibrillation by EMT’s (emergency medical technicians), without the presence of physicians, was first performed in Oregon , in 1969.
- 9. • The electricalshock, by depolarizing all excitable myocardium and possibly by prolonging refractoriness, interrupts reentrant circuits and establishes electrical homogeneity, which terminates reentry • Produces electrical silence or ASYSTOLE • This allows pacemaking cells in heart to recover
- 10. • Defibrillation isnon synchronised delivery of energy during any phase of cardiac cycle • Cardioversion is the delivery of energy synchronised with the large R waves of QRS complex
- 11.
- 12.
- 13.
- 14. INDICATIONS • As arule, any tachycardia that produces hypotension, congestive heart failure, mental status changes, or angina and does not respond promptly to medical management should be terminated electrically. • Very rapid ventricular rates in patients with atrial fibrillation and Wolff-Parkinson-White syndrome are often best treated by electrical cardioversion
- 15. ENERGY REQUIREMENTS • Selectionof appropriate current will reduce the need for multiple shocks and limit the myocardial damage per shock • The energy set too low will leave the heart in ventricular fibrillation and a shock with the energy set too high may leave the heart in asystole or AV block
- 16. • The realtionshipbetween bodysize and energy requirements for defibrillation has been under debate • By the help of prospective out of hospital studies, the first shock energy for defibrillation was set at 200J in the mid 1980s
- 17. Defibrillation waveforms • Twobroad categories : monophasic and biphasic • Biphasic waveforms deliver current that flows in positive direction for a specified duration then reverses and flows in a negative direction for the remaining milliseconds of the electrical discharge • Biphasic waveforms are more superior than monophasic …. Still under investigation and debate
- 18. MONOPHASIC * First-shock efficacy 360J 54%- 63%* 360J 77% - 91%*
- 19. BIPHASIC Up to 85%* * First-shock efficacy 120-200J150-200J 86%—98%*
- 20. • Research hasshown that repititive lower energy biphasic waveforms shocks (<200J) have equivalent or higher success for immediate termination of VF compared with monphasic waveform shocks that escalate the energy (200,300,400J) with successive shocks
- 21. Pads ,Paddles, andPositions • Often neglected topic • Should be placed in a position which maximises current flow through myocardium • Even with proper placement of paddles only 4% to 25% of deliverd current actually passes through heart
- 22. • Recommended placementis termed either sternal- apex or anterior apex • The sternal or anterior electrode is placed to the right of the upper part of the sternum below the clavicle • The apex electrode is placed to the left of the nipple with the center of the electrode in the midaxillary line
- 23. • Alteranative methodis to place one paddle anteriorly over the left apex and the other posteriorly behind the heart in left infrascapular location • Avoid placement directly over any implanted pacemaker or defibrillator
- 24. Syncronised cardioversion • Synchronisationprevents the unwanted induction of VF because it ensures that a shock hits during the absolute refractory period of the cardiac cycle • Recommended in hemodynamically stable, widecomplex tachycardia requiring cardioversion, supraventricular tachycardia, atrial fibrillation and atrial flutter
- 25. Synchronised Cardioversion • • Not effectivein junctional tachycardia multifocal atrial tachycardia or Problems with synchronization • Time delay • Some times shock not delivered
- 26.
- 27. Important Points During Defibrillation • • • • Hairychest Wet chest Breasts Patches Wrenn, K. The hazards of defibrillation through nitroglycerin patches. Ann Emerg Med 1990; 19(11): 1327-8 AICD / pacemaker•
- 28. Important Points During Defibrillation Couplingagent• – NO ARCING!! R. S. Hummel 3rd, J. P. Ornato, S. M. Weinberg and A. M. Clarke. Spark-generating properties of electrode gels used during defibrillation. A potential fire hazard. JAMA November 25, 1988; 260: 20 √
- 29. Defibrillator Burn • Correctuse of coupling agent or defibrillator pads will prevent burns
- 30. Important Points During Defibrillation •Paddle force – 8kg in adult, 5kg in 1-8 year old using adult paddles children when • Paddle size – Minimum 150cm2, diameter 8-12cm
- 31. Important Points During Defibrillation •Paddle position 1. 2. 3. 4. Sternal - apical Biaxillary Right or left upper back – apical Antero-posterior especially in atrial arrhythmias 4 positions are equally effective in shock• All success Deakin CD, Sado DM, Petley GW, Clewlow F. Is the orientation of the apical defibrillation paddle of importance during manual external defibrillation? Resuscitation 2003;56:15—8
- 32. Important Points During Defibrillation ALSSubcommittee 2010
- 33. Important Points During Defibrillation •Fire May be ignited by sparks from poorly applied defibrillator paddles in the presence of an oxygen-enriched atmosphere Miller, P. H. Potential fire hazard in defibrillation. JAMA 1972;221(2): 192. Early report of fire hazard during defibrillation Fires from Defibrillation during Oxygen Administration. Hazard. Health Devices Jul 1994;23(7):307-8 Robertshaw, H. and G. McAnulty. Ambient oxygen concentrations during simulated cardiopulmonary resuscitation. Anaesthesia 1998;53(7): 634-7 Theodorou et al. Fire Attributable to a Defibrillation Attempt in a Neonate. Pediatrics 2003;112:677-679
- 34. Important Points During Defibrillation •One I clear, Two you clear, Three clear everybody • Look back at monitor before shocking • Paddles MUST be horizontal at all times!
- 35. How to defibrillate? stop look go 1. 2. 3. 4. 5. 6. 7. 8. 9. Attach electrodes to patient’s chest Turn defibrillator on – select leads Analyse the rhythm ?shockable Apply coupling agent or Select energy level Apply paddles to chest Charge the paddles The “Clear” chant Check monitor again pads to patient’s chest 10.Discharge shock and return paddles to machine
- 36. If Flatline… • Alwaysdouble check that it IS a flatline – – – Check other leads Check attachment of leads Increase the size of rhythm to rule out fine ventricular fibrillation ALS Subcommittee 2010
- 37. What is wrongwith this picture? ALS Subcommittee 2010
- 40. References 1. American HeartAssociation CPR 2010 Guidelines Nov 2. European Resuscitation Council Guidelines for Resuscitation 2010 3. Braunwald’s textbook of cardiology 9th edition