A sudden cardiac arrest is a life-threatening emergency where the heart’s electrical system malfunctions, causing it to stop pumping blood effectively. The brain and other vital organs are immediately deprived of oxygen, leading to rapid collapse and unresponsiveness. While an Automated External Defibrillator (AED) is the only method to electrically reset the heart’s rhythm, immediate bystander action can keep the person viable until professional help arrives. The goal is not to “restart” the heart electrically, but to manually maintain a minimal flow of oxygenated blood. This manual circulation is critical because every minute without intervention decreases the chance of survival.
Immediate Response and Emergency Activation
The first action is to ensure the scene is safe for both the victim and the rescuer. After confirming safety, the rescuer must check for responsiveness by firmly tapping the person and shouting, “Are you okay?” Unresponsiveness and abnormal breathing, such as gasping, should be interpreted as a sign of cardiac arrest.
The most important step is to immediately call the local emergency number, like 911 in the United States, or instruct a bystander to do so. The caller should put the phone on speaker mode and follow the dispatcher’s instructions, who can provide real-time guidance for performing Cardiopulmonary Resuscitation (CPR). If an AED is visibly nearby, a bystander should be instructed to retrieve it, as early defibrillation is the definitive treatment.
Detailed Steps for Hands-Only Cardiopulmonary Resuscitation
For an untrained bystander, the current recommendation for an adult is to perform hands-only CPR, which focuses solely on chest compressions without rescue breaths. This method simplifies the procedure and minimizes interruptions, providing the best chance for survival. The first step for effective compressions is to position the victim flat on their back on a firm surface, such as the floor or the ground.
To begin compressions, the rescuer should kneel beside the person and place the heel of one hand directly on the center of the chest, on the lower half of the breastbone. The second hand is then placed on top of the first, with the fingers interlaced and lifted off the person’s chest. This technique ensures the pressure is applied through the heel of the hand, reducing the risk of injury.
The rescuer must position their shoulders directly over their hands, keeping arms straight and using body weight, not just arm muscles, to press down. Each compression needs to be at least 2 inches deep, but no more than 2.4 inches, to be effective in circulating blood. It is equally important to allow the chest to fully recoil to its original position after each push, letting the heart refill with blood.
Compressions must be performed at a rapid rate of 100 to 120 beats per minute, which can be maintained by pushing to the rhythm of familiar songs like “Stayin’ Alive.” This consistent and fast pace is necessary to generate enough blood pressure to keep the brain and heart supplied with minimal oxygen. The rescuer should continue high-quality, hands-only compressions without interruption until emergency medical services arrive or the person begins to move.
Understanding Circulation Maintenance Versus Electrical Restart
The premise of “restarting a heart” is a medical misunderstanding, as the process of CPR is fundamentally different from defibrillation. CPR, through chest compressions, manually squeezes the heart between the sternum and the spine, acting as an external pump. This mechanical action maintains a low, but life-sustaining, flow of oxygenated blood to the brain and heart muscle.
Manual circulation maintenance keeps the heart muscle viable, which is essential because defibrillation is less likely to succeed on a heart deprived of oxygen. Defibrillation delivers an electrical shock to stop chaotic electrical activity, such as ventricular fibrillation. By momentarily stopping all electrical activity, the hope is that the heart’s natural pacemaker, the sinoatrial node, can re-establish a normal, organized rhythm.
The electrical shock from a defibrillator is the only intervention that addresses the underlying electrical problem, whereas CPR only buys time. CPR preserves the viability of the patient’s cells until definitive electrical treatment or advanced medical care can be provided. This distinction explains why CPR and defibrillation are complementary techniques, with CPR acting as the bridge to definitive care.
Techniques Reserved for Advanced Rescuers
Certain techniques, such as the precordial thump or “cough CPR,” are sometimes discussed but are not recommended for use by untrained lay rescuers. The precordial thump involves delivering a sharp blow to the middle of the sternum with a closed fist, which is thought to generate a small electrical impulse. However, its effectiveness is limited and confined to monitored situations, such as in a hospital where the cardiac rhythm is immediately confirmed.
Similarly, “cough CPR” is a highly situational technique where a conscious person experiencing an arrhythmia repeatedly coughs forcefully to maintain blood pressure. This technique is not applicable to a person who has collapsed and is unresponsive, which is the state of cardiac arrest requiring bystander intervention. Lay rescuers should focus exclusively on immediate emergency activation and continuous, high-quality hands-only CPR, as these are the proven, life-saving actions for the public.