A patient develops cardiac arrest during a dental procedure. The patient has no pulse. Which intervention is most critical for survival?

The most survivable cause of sudden cardiac arrest is ventricular fibrillation (VF), which can only be terminated by defibrillation. An AED analyzes the cardiac rhythm and delivers an electrical shock to restore organized electrical activity when a shockable rhythm (VF or pulseless VT) is detected. Early defibrillation is the most critical intervention for survival: survival rates decrease approximately 10% for each minute of delay. CPR (chest compressions) provides vital blood flow to the brain and heart while awaiting and during defibrillation, but CPR alone cannot convert VF. The dental office emergency protocol: activate EMS, begin CPR, retrieve and apply the AED as quickly as possible. AED + CPR together maximize survival outcomes.