How to Identify the Signs of Cardiac Arrest

When someone suddenly collapses, it's crucial to determine whether the cause is cardiac arrest or another condition such as fainting. Below are the key indicators to help identify cardiac arrest:

Loss of Consciousness

Sudden unresponsiveness is one of the first signs of cardiac arrest. When the heart stops beating effectively, blood flow to the brain is interrupted, often causing the person to lose consciousness abruptly. This is different from fainting, which typically involves a gradual loss of awareness.

Seizure-Like Activity

Uncontrolled Body Movements

In some cases, a person experiencing cardiac arrest may exhibit violent or seizure-like shaking, especially in the arms and legs. This unusual movement can be misleading, as it resembles epileptic seizures, but it's often a sign of the brain not receiving enough oxygen due to heart failure.

Checking for a Pulse

Assessing Circulation

One of the most reliable ways to confirm cardiac arrest is to check for a pulse in the major arteries, such as the carotid artery in the neck. If there is no pulse, listen for heart sounds. In a clinical setting, medical professionals may use an ECG (electrocardiogram) to verify that the heart has stopped beating and that the rhythm is flatlined.

Pupil Dilation

Eye Response as an Indicator

Significant pupil dilation is another critical sign. In most non-cardiac emergencies, the pupils remain normal in size. However, within 30 seconds to a minute after cardiac arrest, the pupils may begin to dilate due to lack of oxygenated blood flow to the brain.

Immediate Action is Essential

If the above symptoms are present, it's vital to begin emergency response procedures immediately. Call for professional medical help, start CPR if trained, and use an AED (automated external defibrillator) if available. Quick action can significantly increase the chances of survival.