Sudden loss of responsiveness: The person may suddenly collapse, not respond to your voice or touch, and appear unconscious.
Absence of normal breathing: The individual may not be breathing or only gasping irregularly. Gasping is not normal breathing and is a sign of a medical emergency.
No pulse or palpable heartbeat: When you check for a pulse at the carotid artery (neck) or the wrist, you may not detect any, indicating a cardiac emergency.
Blue or pale skin: The person's skin may turn blue or very pale due to lack of oxygen circulation.
Chest discomfort or pain: Some individuals may experience chest pain or discomfort shortly before the cardiac arrest occurs.
Dizziness or lightheadedness: Prior to collapsing, the person might feel dizzy or light-headed.
Nausea or vomiting: Some individuals might experience these symptoms before or during a cardiac arrest.
Sweating: Cold and clammy skin or heavy sweating can be observed in the person experiencing cardiac arrest.