What is the first link in the out-of-hospital cardiac arrest (OHCA) Chain of Survival?

The first link in the out-of-hospital cardiac arrest (OHCA) Chain of Survival is the activation of emergency response. This step is crucial because it initiates the process of seeking help and mobilizes the resources needed to address the cardiac arrest. When bystanders recognize a person in cardiac arrest, they must quickly call emergency services to ensure that advanced medical support can arrive as soon as possible. This action sets the stage for subsequent critical interventions, such as performing CPR and providing defibrillation.

Activating the emergency response immediately connects the situation with professional medical assistance, which is essential for improving the chances of survival. This prompt action can lead to rapid deployment of advanced care, which is vital given that brain death and irreversible damage to vital organs can begin to occur within minutes of cardiac arrest. Each subsequent link in the Chain of Survival builds on the activation step, emphasizing its foundational role in the overall response to OHCA.