Survival rates vary significantly; favorable factors include Early and effective bystander-initiated CPR Witnessed arrest In-hospital location (particularly a monitored unit) Initial rhythm of ventricular fibrillation (VF) or ventricular tachycardia (VT) Early defibrillation of VF or VT Postresuscitative care, including circulatory support and access to cardiac catheterization In adults, targeted temperature management (body temperature of 32 to 36° C for ≥ 24 hours) and avoidance of hyperthermia While the American Heart Association 2020 Advanced Cardiac Life Support (ACLS) guidelines recommend cooling to a temperature range between 32° C and 36° C, more recent recommendations from the International Liaison Committee on Resuscitation Advanced Life Support (ALS) suggest actively preventing fever with a target temperature of ≤ 37.5° C rather than active cooling.