Factors associated with a poor outcome after witnessed out-of-hospital sudden cardiac arrest include an initial rhythm of pulseless electrical activity or asystole, time elapsed prior to effective resuscitation through delayed bystander CPR or defibrillation, prolonged CPR lasting over 5 minutes, absence of vital signs after CPR, advanced age, prior history of cardiac disease, having two or more chronic illnesses, remaining in a coma after CPR, and developing pneumonia, renal failure, sepsis, stroke, or severe heart failure after receiving CPR.

1. Factors associated with poor outcome after witnessed out-of-
hospital sudden cardiac arrest
• Time elapsed prior to effective resuscitation (delayed bystander
CPR, delayed defibrillation)
• Initial rhythm of pulseless electrical activity or asystole
• Prolonged CPR (>5 minutes)
• Absence of vital signs
• Advanced age
• Prior history of cardiac disease
• ≥ 2 chronic illnesses
• Persistent coma after CPR
• Need for intubation or vasopressors
• Pneumonia or renal failure after CPR
• Sepsis, cerebrovascular accident, or class III or IV heart failure