This document discusses defibrillation, cardioversion, and pacing. It provides:
1) A brief history of defibrillation and its use for ventricular fibrillation and pulseless ventricular tachycardia.
2) An overview of cardioversion for treating unstable tachyarrhythmias with signs of low cardiac output, excessive heart rates, or chest pain. Synchronized cardioversion times shock delivery to the QRS complex.
3) Information on pacing for unstable bradyarrhythmias and symptomatic bradycardia, including complete heart block and Mobitz type II second-degree heart block.
7. Defibrillation
History
1900 defibrillation discovery
1947 human defibrillation
1967 successful outside hospital defibrillation
For VF or pulseless VT
Defibrillation (shock success) termination of
VF for at least 5s following shock
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19. 1st degree heart block
Lengthened P-R interval > 0.2 sec (> 5 small
boxes)
Partial AV node block
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20. 2nd Degree Heart Block
Mobitz Type I 2nd degree AV block
A cycle of progressive lengthening of PR
interval followed by absence of QRS complex
Wenkebach Phenomeno
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21. *Mobitz Type II 2nd Degree Heart Block
Intermittent absence of QRS complex
(non-conducted P wave)
PR interval normal
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22. *Complete/ 3rd degree heart block
Variable conduction origins
Lack of synchronization between atria and
ventricles
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25. Take home message
Recognize ECG findings
Indications for defibrillation, cardioversion and
pacing
How to do it
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26. Thank you
Ref:
1. Tintinallis Emergency Medicine Manual, 7th Edition
2. AHA ACLS 2010; Electrical therapy
3. Basic and Advanced Life Support 2005 by K.S.Chew,
emergency department USM
4. ECG Teaching by Dr Effa, cardiologist, Medical faculty
UiTM
5. http://www.ecglibrary.com
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Editor's Notes
Normal ecg
VF:
Chaotic irregular deflections of varying amplitude
No identifiable P waves, QRS complexes, or T waves
Rate 150 to 500 per minute