During a cardiac arrest, a combined Defib Monitor allows the operator to analyse and monitor the ECG while also immediately delivering a defibrillating countershock to patients suffering from ventricular fibrillation. These units also enable synchronised cardioversion for the treatment of various arrhythmias, including as ventricular tachycardia, and most also include noninvasive external pacemaker capabilities for the treatment of patients with ventricular bradycardia or asystole. Defib Monitor is an important resuscitation equipment that must work properly to prevent the death of a cardiac arrest patient who would otherwise die.