What should you do first if you see a man collapse and he is not breathing?

In a situation where a person has collapsed and is not breathing, the immediate priority is to provide chest compressions as part of cardiopulmonary resuscitation (CPR). The rationale for starting with chest compressions is that they help maintain vital blood flow to the heart and brain, which is critical in preventing irreversible damage and increasing the chances of survival.

When a person is unconscious and not breathing, this indicates a potential cardiac arrest, and initiating chest compressions without delay can be critical. These compressions pump blood through the body artificially, helping to keep organs perfused until professional help can arrive or until an automated external defibrillator (AED) can be used.

While calling 911 and other responses are also crucial actions, the priority in emergency care, especially in cases of cardiac arrest, is to start circulation through chest compressions immediately. This approach aligns with protocols recommended by organizations like the American Heart Association.