During CPR, how many chest compressions are given before rescue breaths?

• A. 15 compressions followed by 1 breath.
• B. 20 compressions followed by 2 breaths.
• C. 45 compressions followed by 3 breaths.
• D. 30 compressions followed by 2 rescue breaths.

Answer: (D)

The main idea is to keep blood flowing with chest compressions while still providing enough breaths to oxygenate the blood. For an adult in one-rescuer CPR, the recommended pattern is to perform thirty chest compressions in a row, then give two rescue breaths, and repeat. This 30:2 cycle balances maximizing circulation with providing ventilation: too many breaths or long pauses would drop blood flow, while too few compressions would limit perfusion. The pace should be about 100–120 compressions per minute with a depth of about 2 inches (5 cm) and full chest recoil between compressions.