Features indicating unfavourable outcome after CPR in OHCA

Features indicating unfavourable outcome after cardiopulmonary resuscitation in out of hospital cardiac arrest: 1. Unwitnessed cardiac arrest - delay in initiation of cardiopulmonary resuscitation likely to be high. 2. Initial cardiac rhythm other than ventricular fibrillation - meaning that it is a non shockable rhythm. May also indicate that there has been a delay after the onset of cardiac arrest and monitoring so that an initial shockable rhythm has deteriorated into a non shockable rhythm. 3. No bystander CPR has been received - indicates likelihood of more cerebral anoxia and poor outcome after resuscitation even if return of spontaneous circulation (ROSC) is achieved. 4. Ongoing CPR - no return of spontaneous circulation yet Took more than 30 minutes of resuscitation for return of spontaneous circulation 5. Severe acidosis with pH less than 7.2 6. Lactate levels above 7 millimoles per liter 7. Age above 85 years 8. End stage renal disease 9. Non cardiac causes like trauma causing cardiac arrest