How to Identify the Signs of Cardiac Arrest

Recognizing cardiac arrest promptly can be life-saving. There are three key indicators to look for when determining if someone is experiencing cardiac arrest.

1. Loss of Consciousness

The first step is to check for responsiveness. Gently tap the person's shoulders and shout to see if they respond. If there is no reaction—no movement, speech, or eye opening—it is likely that they have lost consciousness. This is a critical early sign of cardiac arrest.

2. Absence of Normal Breathing

Next, assess the person's breathing. In cases of cardiac arrest, breathing may either stop completely or present as abnormal gasping, often described as agonal respirations. These breaths can resemble snoring, snorting, or labored gasping and are not normal breathing patterns. Take a close look and listen carefully for no more than 10 seconds to make this determination.

Common Breathing Signs in Cardiac Arrest

Some individuals may exhibit what's known as "agonal breathing," which can be mistaken for regular breathing. It's important to understand that this type of breathing is not effective and indicates a medical emergency requiring immediate action.

3. Absence of a Pulse

The final indicator is the absence of a pulse in major arteries. The most accessible artery to check is the carotid artery, located in the groove between the cricoid cartilage and the sternocleidomastoid muscle on the neck. If the person has a neck injury and the carotid pulse cannot be assessed safely, alternative arteries such as the radial, brachial, or femoral may be used.

How to Check for a Pulse

Place two fingers gently on the side of the neck and press lightly to feel for a pulse. This should be done quickly—within 10 seconds—to avoid delays in initiating life-saving interventions. If no pulse is detected, it confirms the likelihood of cardiac arrest and the need for immediate CPR and emergency medical assistance.