How quickly does the chance of survival decline for every minute of defibrillation delay in patients with VF who do not receive CPR?

How quickly does the chance of survival decline for every minute of defibrillation delay in patients with VF who do not receive CPR?

• A. 0%
• B. 7-10%
• C. 20-30%
• D. 5%

Answer: (B)

In ventricular fibrillation, there’s no effective blood flow, so brain and heart tissue rapidly become ischemic. If defibrillation is delayed and no CPR is performed, the chance of surviving to discharge falls quickly, about 7–10% for each minute that passes before a shock is delivered. This steep drop happens because the longer the heart stays in VF, the less likely the heart is to respond to defibrillation and the greater the risk of permanent neurological and organ damage. Early defibrillation maximizes the odds of returning a perfusing rhythm and preserving brain function. The other options don’t fit because zero decline isn’t realistic, 5% underestimates the rapid time-sensitive loss, and 20–30% overestimates the typical per-minute drop seen in ACLS guidance.

In ventricular fibrillation, there’s no effective blood flow, so brain and heart tissue rapidly become ischemic. If defibrillation is delayed and no CPR is performed, the chance of surviving to discharge falls quickly, about 7–10% for each minute that passes before a shock is delivered. This steep drop happens because the longer the heart stays in VF, the less likely the heart is to respond to defibrillation and the greater the risk of permanent neurological and organ damage. Early defibrillation maximizes the odds of returning a perfusing rhythm and preserving brain function. The other options don’t fit because zero decline isn’t realistic, 5% underestimates the rapid time-sensitive loss, and 20–30% overestimates the typical per-minute drop seen in ACLS guidance.