Cardiopulmonary Resuscitation (CPR) is an emergency technique combining chest compressions and rescue breathing, or compressions alone, performed when a person’s heart or breathing has stopped. The goal of CPR is to manually circulate oxygenated blood to the brain and vital organs to delay tissue death until medical help arrives. This action is specifically intended for victims of cardiac arrest, where the heart is not beating effectively or at all. The distinction between a life-saving intervention and potential harm relies entirely on correctly assessing the patient’s condition, particularly the presence or absence of a pulse.
The Critical Pre-CPR Assessment
The initial assessment determines whether CPR is necessary. A rescuer determines if the person is unresponsive by tapping them and asking loudly if they are okay. If there is no response, check for normal breathing and a pulse simultaneously, taking no more than 10 seconds. CPR is mandated only when the person is unresponsive and either not breathing or exhibiting abnormal gasping breaths (agonal respirations).
If a pulse is absent, or if the rescuer cannot confidently detect one within that 10-second window, the person is presumed to be in cardiac arrest, and chest compressions must begin immediately. Trained rescuers check for a pulse using the carotid artery. However, because untrained rescuers often struggle to accurately detect a pulse, modern guidelines emphasize starting compressions quickly if the person is unresponsive and not breathing normally. CPR is designed to support a heart that has stopped, not one that is merely beating slowly or weakly.
Physical Consequences of Unnecessary Compressions
Performing forceful chest compressions on a person who already has a functional heartbeat and pulse can cause significant, unnecessary trauma. Compressions are administered hard and fast, pushing the sternum down at least two inches in an adult to squeeze the heart between the sternum and the spine. When the heart is beating effectively, this force can interrupt its natural rhythm and cause mechanical damage to the chest cavity.
The most common mechanical injuries include fractured ribs and sternal fractures. While these injuries are an accepted consequence when saving a life, they are unwarranted when a pulse is present. Furthermore, the downward force risks damaging underlying structures like the lungs or the liver, which can lead to life-threatening internal bleeding.
Beyond mechanical trauma, a severe risk is the disruption of the heart’s electrical system, potentially inducing a life-threatening arrhythmia. The blunt force can trigger ventricular fibrillation, a chaotic heart rhythm where the heart’s lower chambers only quiver instead of pumping blood. This converts a patient who was stable into one experiencing actual cardiac arrest requiring immediate defibrillation. Unnecessary CPR can turn an ill patient into a trauma victim with a newly induced heart emergency.
Immediate Protocol When a Pulse is Present
When a rescuer confirms that an unresponsive person has a pulse, the immediate focus shifts from full CPR to supportive care and emergency activation. The first step is to call emergency medical services (EMS), such as 911. The person should be carefully monitored to ensure they do not lose the pulse while waiting for EMS to arrive.
If the person has a pulse but is not breathing normally, or is breathing too slowly, the correct intervention is rescue breathing, or ventilation, without chest compressions. For an adult, a rescuer should deliver one breath every five to six seconds, aiming for about 10 to 12 breaths per minute. Each rescue breath should be given over one second and should be just enough to make the chest visibly rise.
If the person remains unresponsive but is breathing normally and has a pulse, they should be placed into the recovery position. This position helps keep the airway open and prevents aspiration if they were to vomit. The rescuer must continue to monitor the pulse and breathing closely until the EMS team takes over care, as a person’s condition can change rapidly.