As a medical professional with expertise in neurology, I can provide insight into the question of how long a person can survive without oxygen. When the blood flow to the brain is cut off, the supply of oxygen and nutrients is also halted. Brain cells begin to die after approximately 4-6 minutes without blood flow. If this lack of oxygen continues, after about 10 minutes, the cells will have sustained irreversible damage and will be effectively dead. It's important to note that these timeframes are general estimates and can vary based on individual health, age, and other factors. Immediate medical intervention, such as CPR or the use of an automated external defibrillator (AED), can be critical in attempting to restore blood flow and prevent brain death. read more >>

If not, you typically don't. For this, a general rule of thumb is that brain cells begin to die after approximately 4-6 minutes of no blood-flow. After around 10 minutes, those cells will cease functioning, and be effectively dead.read more >>