Editing Defibrillation (section)

{{Short description|Treatment for life-threatening cardiac arrhythmias}}
{{Distinguish|infibulation|Defibrator}}
{{Infobox medical intervention
| name         = Defibrillation
| image        = Defibrillation Electrode Position.jpg
| caption      = View of defibrillator electrode position and placement
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| ICD10        =
| ICD9         =
| ICD9unlinked =
| MeshID       = D047548
| LOINC        =
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}}

'''Defibrillation''' is a treatment for life-threatening [[cardiac arrhythmia]]s, specifically [[ventricular fibrillation]] (V-Fib) and [[ventricular tachycardia|non-perfusing ventricular tachycardia]] (V-Tach).<ref name="Tintinalli" /><ref name="Kerber" /> A defibrillator delivers a dose of [[electric current]] (often called a ''counter-shock'') to the [[heart]]. Although not fully understood, this process [[depolarization|depolarizes]] a large amount of the [[cardiac muscle|heart muscle]], ending the arrhythmia. Subsequently, the body's [[cardiac pacemaker|natural pacemaker]] in the [[sinoatrial node]] of the heart is able to re-establish normal [[sinus rhythm]].<ref name="Werman" /> A heart which is in [[asystole]] (flatline) cannot be restarted by a defibrillator; it would be treated only by [[cardiopulmonary resuscitation]] (CPR) and medication, and then by cardioversion or defibrillation if it converts into a shockable rhythm.

In contrast to defibrillation, synchronized electrical [[cardioversion]] is an electrical shock delivered in synchrony to the [[cardiac cycle]].<ref name="Basic principles and technique of external electrical cardioversion and defibrillation" /> Although the person may still be [[critically ill]], cardioversion normally aims to end poorly perfusing [[cardiac arrhythmia]]s, such as [[supraventricular tachycardia]].<ref name="Tintinalli" /><ref name="Kerber" />

Defibrillators can be external, transvenous, or [[implant (medicine)|implanted]] ([[implantable cardioverter-defibrillator]]), depending on the type of device used or needed.<ref name="Hoskins" /> Some external units, known as [[automated external defibrillator]]s (AEDs), automate the diagnosis of treatable rhythms, meaning that lay responders or bystanders are able to use them successfully with little or no training.<ref name="Kerber" />