Final answer:
Brain damage is likely within 4 to 6 minutes after the heart stops beating, highlighting the urgency of initiating CPR immediately to maintain blood flow and oxygen delivery to the brain.
Step-by-step explanation:
Brain damage is likely within 4 to 6 minutes after a victim stops breathing and the heart stops beating. Cells in the brain are extremely sensitive to lack of oxygen because they require a constant and high level of energy production. When the heart has stopped, CPR (cardiopulmonary resuscitation) can be a critical lifesaving technique, as it helps to manually compress the blood within the heart to maintain the flow of blood, especially to the brain, to prevent irreversible damage or death of neurons.
It's important to administer CPR as soon as possible to increase the chances of survival and recovery. Even in situations where the heart has stopped, if CPR is initiated quickly, there can still be a chance of recovery. The chances of survival are even higher for individuals, such as children, who fall into very cold water since hypothermia can extend the time the brain can survive without oxygen.