Cardiac arrest leads to loss of consciousness and death unless emergency resuscitation is given and the heart can be restarted. The abnormal cardiac rhythms most commonly associated with cardiac arrest are asystole, pulseless electrical activity, ventricular fibrillation and pulseless ventricular tachycardia. Brain injury after cardiac arrest may be prevented by early cardiopulmonary resuscitation, including defibrillation to treat ventricular fibrillation and pulseless ventricular tachycardia rhythms. Drugs such as adrenaline are also commonly needed (Therapeutic hypothermia following cardiac arrest [NICE interventional procedure guidance 386]).
Treatment of unconscious survivors after cardiac arrest accounted for 5.6% of the total UK adult general intensive care unit bed days in the Intensive Care National Audit and Research Centre Case Mix Programme Database (ICNARC CMPD), which shows the impact of the condition on NHS resources (Nolan et al. 2007).