What physiological response occurs during sudden cardiac arrest?

During sudden cardiac arrest, one of the primary physiological responses is the occurrence of electrical disturbances in heart rhythm. This disruption happens because cardiac arrest is often triggered by arrhythmias, which are irregular heartbeats that can prevent the heart from effectively pumping blood. Such electrical disturbances may lead to conditions like ventricular fibrillation, where the heart quivers ineffectively rather than contracting normally, thus failing to circulate blood.

Understanding the nature of cardiac arrest emphasizes the importance of quick intervention, such as defibrillation, which aims to restore a normal rhythm to the heart. By recognizing that the heart's electrical activity is compromised during this critical event, lifeguards and responders can prioritize their actions around restoring heart function effectively.