Brain damage begins after how many minutes of cardiac arrest?

• A. 1-2 Minutes
• B. 7-9 Minutes
• C. 10+ Minutes
• D. 4-6 Minutes

Answer: (D)

Brain tissue is highly vulnerable to oxygen deprivation, so when circulation stops during cardiac arrest, brain cells rapidly run out of energy and ion pumps fail. Neurons become irreversibly injured after a brief window of oxygen deprivation, and this injury accelerates as time without perfusion passes. Around four to six minutes without circulation, brain cells begin to die and damage becomes more widespread if flow isn’t restored. After longer delays, such as ten minutes or more, the chances of meaningful neurological recovery drop significantly. That’s why immediate, high-quality CPR and rapid restoration of circulation are critical to preserving brain function. Therefore, the window when brain damage begins is roughly four to six minutes.