A witnessed cardiac arrest occurs when the heart suddenly stops beating while observed by another person. This severe medical emergency prevents blood flow to the body and brain. Prompt bystander action is crucial, as the individual will become unresponsive and cease normal breathing or exhibit abnormal gasping.
Initial Steps: Call and Compressions
Recognizing a witnessed cardiac arrest requires immediate action. First, check for responsiveness and normal breathing. If the individual is unresponsive and not breathing normally, call emergency services (e.g., 911) without delay. If another person is present, direct them to retrieve an automated external defibrillator (AED) if one is nearby.
Once emergency services are alerted, begin high-quality chest compressions immediately. CPR involves manually pumping blood by compressing the chest, which helps maintain blood flow to the brain and other organs. This continuous circulation helps prepare the heart for defibrillation and improves the chances of a successful outcome.
AED Deployment and Use
Once chest compressions begin, apply the automated external defibrillator (AED) as soon as it is available. An AED is a portable device that analyzes the heart’s rhythm and delivers an electrical shock if needed to restore a normal heartbeat. Prompt AED application, especially within the first few minutes, significantly increases survival rates from sudden cardiac arrest.
To use an AED, turn it on and follow its voice prompts. Expose the individual’s bare, dry chest. Firmly attach the adhesive pads as indicated, typically one on the upper right chest and the other on the lower left below the armpit.
Once pads are connected, the device analyzes the rhythm and advises if a shock is necessary. Before delivering a shock, ensure no one is touching the individual by announcing “CLEAR!” The AED will then instruct you to press the shock button if advised.
Continuing Care Until Help Arrives
After a shock, or if the AED advises no shock, immediately resume chest compressions. Continue CPR for two minutes before the AED re-analyzes the heart’s rhythm. The AED will prompt when to pause compressions for analysis and potential shocks.
Do not remove the AED pads or turn off the device until professional medical personnel arrive. Continuous CPR, with brief interruptions only for AED analysis or shock delivery, is fundamental to maintaining blood flow and maximizing recovery chances. The AED will continue guiding the rescuer through cycles of CPR and analysis until emergency medical services (EMS) are on scene.
Why Every Second Counts
The swift sequence of actions—calling for help, performing chest compressions, and applying an AED—is crucial in a witnessed cardiac arrest. Without immediate intervention, brain cells can sustain irreversible damage within minutes due to lack of oxygen. Early defibrillation, delivered by an AED, is the most effective way to address the abnormal electrical activity causing cardiac arrest.
Combining immediate CPR with early defibrillation significantly improves survival chances and neurological outcomes. For every minute without defibrillation, survival probability decreases notably. Acting quickly and effectively makes a substantial difference in preserving life and reducing long-term complications.