What is the compression to ventilation ratio when performing CPR on an adult?

The correct answer is based on established guidelines for performing cardiopulmonary resuscitation (CPR) on adults, which specify a compression to ventilation ratio of 30:2. This means that for every 30 chest compressions delivered, the rescuer should provide 2 rescue breaths.

This ratio is designed to deliver effective circulatory support while also ensuring that oxygen is supplied to the victim's lungs. The emphasis on 30 compressions followed by 2 breaths allows for a more significant number of compressions to maintain blood flow to vital organs, especially the heart and brain, which is crucial during a cardiac arrest scenario.

Adhering to this ratio maximizes the chances of survival and recovery for the victim. It reflects the priority of maintaining circulatory flow while also ensuring oxygenation, which is critical in emergency situations.