What To Do if You Witness A Sudden Cardiac Arrest

If you witness someone collapse due to cardiac arrest, it's important to act quickly. Follow these steps, which are commonly referred to as the "Chain of Survival":

1. Check for Responsiveness: Approach the person and try to wake them up by tapping their shoulders and shouting loudly, "Are you okay?" If there is no response, the person may be unresponsive.

2. Call for Emergency Help: Immediately dial your local emergency number (e.g., 911) to request an ambulance. Clearly state that you have witnessed a cardiac arrest and provide your exact location.

3. Start CPR (Cardiopulmonary Resuscitation): Begin chest compressions. Place the heel of one hand on the center of the person's chest, just below the nipple line. Place your other hand on top and interlock your fingers. Position yourself with your shoulders directly over your hands and use your full body weight to compress the chest at a rate of about 100-120 compressions per minute. Allow the chest to fully recoil after each compression.

4. Use an AED if Available: If an Automated External Defibrillator (AED) is nearby, have someone fetch it and follow its instructions. If you are alone, call for help first and start CPR, then use the AED as soon as it arrives.

5. Continue CPR: Keep performing chest compressions until either the person shows signs of life (such as breathing) or trained medical personnel take over. 

Remember:
- If you're unsure about performing rescue breaths, hands-only CPR (chest compressions without rescue breaths) is still effective and highly recommended.
- It's better to do something than nothing. Prompt action, especially initiating CPR, significantly improves the chances of survival.
 
Always seek professional medical help as soon as possible. These steps can help sustain vital blood flow until more advanced medical care arrives.