Out-of-hospital cardiac arrest (OHCA) is a significant public health issue. In Australia, more than 30,000 OHCAs occur every year, with fewer than 10% surviving to leave hospital (Ambulance Victoria, 2016). However, with immediate resuscitation more lives can be saved.
In cardiac arrest, the heart is no longer pumping, blood flow stops, the casualty loses consciousness and they will not be breathing normally. This person will die, unless blood flow is restored within a short period of time. Immediate cardiopulmonary resuscitation (CPR) will restore some blood flow.
For a short period of time, the non-pumping heart may have an abnormal rhythm such as ventricular fibrillation (VF) or ventricular tachycardia (VT). These two rhythms can be “shocked” by a defibrillator, back into a normal pumping rhythm.