A pacemaker is a small, battery-operated device implanted beneath the skin, typically near the collarbone, designed to regulate the heart’s rhythm by delivering low-energy electrical pulses. Cardiopulmonary Resuscitation (CPR) is a life-support intervention performed when the heart stops pumping effectively. If a person with an implanted pacemaker collapses, is unresponsive, and is not breathing, CPR must be performed immediately. The presence of a pacemaker does not negate the need for immediate, high-quality chest compressions.
The Necessity of Immediate CPR and Rescuer Safety
Cardiac arrest causes brain damage to begin within minutes, making immediate action paramount. A pacemaker prevents abnormally slow or irregular heart rhythms, but it cannot prevent all causes of cardiac arrest or restart a heart that has completely stopped beating. If the person is unconscious and not breathing, the pacemaker is not sufficient, and intervention is required.
Rescuers often worry about the risk of electric shock from the implanted device. Pacemakers deliver only very low-energy electrical impulses that pose no risk of electrocution to the person performing chest compressions or rescue breaths. The pacemaker is entirely self-contained and shielded within the body.
The mechanical force of chest compressions will not endanger the rescuer. Focusing on the urgency of providing circulatory support is far more important than worrying about the implanted device. This immediate action keeps oxygenated blood flowing to the brain and other organs until advanced medical help arrives.
Proper Hand Placement During Chest Compressions
Standard CPR technique requires placing the heel of the hand on the center of the chest, on the lower half of the sternum. Pacemakers are generally implanted in the upper chest, often just below the collarbone, presenting as a small, palpable bulge under the skin. This location is typically on the left side, though it can sometimes be on the right.
Compressing directly over the pacemaker can potentially damage the device or, in rare cases, cause injury to the patient by pushing the device deeper into the chest wall. To avoid this, rescuers should quickly locate the device site, which may be visible or felt as a small lump.
The heel of the hand should then be positioned centrally on the sternum, avoiding the pacemaker site. This slight adjustment ensures the compression force is directed to the middle of the chest, where it is most effective for circulating blood. The standard compression depth of at least two inches and the rate of 100 to 120 compressions per minute remain unchanged.
Using an Automated External Defibrillator (AED)
Using an Automated External Defibrillator (AED) involves delivering a therapeutic electrical shock. The presence of a pacemaker is not a reason to withhold defibrillation, as the AED is the definitive treatment for certain life-threatening heart rhythms. If an AED is available, it should be used immediately.
The electric current pathway created by the AED pads must not pass directly through the pacemaker generator, as this could damage the device or interfere with its function. Standard AED pad placement involves one pad on the upper right chest, below the collarbone, and the second pad on the lower left rib cage.
When using an AED on a person with a pacemaker, the rescuer must first locate the implanted device. If standard pad placement would put an AED pad directly over the pacemaker, the pad must be shifted. The correct adjustment is to place the AED pad at least one inch away from the visible or palpable outline of the pacemaker. This modification ensures the device is not damaged while allowing the necessary electrical current to pass through the heart.