What emergency procedure is indicated by the need for CPR?

Cardiopulmonary resuscitation (CPR) is specifically indicated in cases of cardiac arrest, where the heart has stopped beating and blood is no longer being pumped to the rest of the body. The primary goal of CPR is to restore circulation and breathing, thereby maintaining vital organ function until advanced medical care can be administered.

In cardiac arrest, both the heart's electrical activity and mechanical pumping have ceased, leading to a life-threatening situation requiring immediate intervention. This includes chest compressions to create artificial circulation and, if possible, rescue breaths to address any accompanying respiratory failure.

In contrast, while respiratory failure, severe bleeding, and shock are all critical conditions that may require emergency intervention, they do not specifically dictate the use of CPR as the immediate response. For instance, respiratory failure might be managed with oxygen therapy or mechanical ventilation, severe bleeding could require direct pressure or surgical intervention, and shock might be treated with intravenous fluids and medications to improve blood flow. Therefore, among the options presented, cardiac arrest uniquely necessitates the CPR protocol.