EMT Basic Certification Complete Practice Exam 2025

In CPR for adults, the recommended compression to ventilation ratio of 30:2 is based on guidelines established by organizations like the American Heart Association. This ratio signifies that for every 30 chest compressions, two rescue breaths should be provided. This approach is designed to ensure an adequate balance between chest compressions, which are crucial for maintaining blood circulation, and rescue breaths, which help to oxygenate the blood.

Chest compressions are essential as they create artificial circulation, delivering oxygen-rich blood to vital organs. The ratio of 30 compressions to 2 breaths is optimal for adults because it allows rescuers to maintain a higher focus on compressions, which is critical for improving survival rates in cardiac arrest situations. The two rescue breaths delivered after the compressions help replenish the oxygen supply in the blood without excessive interruption of the compressions.

The other options do not align with the current consensus on adult CPR practices. Ratios like 15:2 or 20:2 may be applicable in different contexts (e.g., child or infant CPR) or specific scenarios but are not recommended for adult victims under standard guidelines. A ratio of 10:1 would significantly reduce the number of ventilations provided, which could be detrimental in ensuring oxygen delivery during res