Which option best describes the recommended chest compression parameters for adults?

Which option best describes the recommended chest compression parameters for adults?

• A. Compress 1 inch; rate 60/min; 15:2
• B. No depth requirements; continuous CPR
• C. Compress 3 inches; rate 140/min; 60:2
• D. Compress 2 inches; rate 100-120/min; 30:2

Answer: (D)

Effective CPR for adults relies on three key elements: how deep the chest is compressed, how fast those compressions are delivered, and the rhythm of compressions to breaths. The goal is to perfuse vital organs while minimizing interruptions. Compressing about 2 inches (around 5 cm) deep ensures enough blood is pushed with each push. The rate should be steady at 100–120 compressions per minute to maintain consistent flow. For a single rescuer, the standard cycle is 30 compressions followed by 2 breaths, balancing chest compressions with ventilation. The option that matches these three aspects—2-inch depth, 100–120/min, and a 30:2 compression-to-breath ratio—is the best choice. Why the others aren’t suitable: one option uses only about 1 inch of depth and a slow rate with an unusual 15:2 ratio, which underperforms for adult perfusion. Another says there are no depth requirements and promotes continuous CPR, which isn’t aligned with current guidelines. The last option proposes too deep a depth (3 inches) and a rate that's too fast (140/min) with an uncommon ratio, increasing risk and deviating from recommended practice.

Effective CPR for adults relies on three key elements: how deep the chest is compressed, how fast those compressions are delivered, and the rhythm of compressions to breaths. The goal is to perfuse vital organs while minimizing interruptions.

Compressing about 2 inches (around 5 cm) deep ensures enough blood is pushed with each push. The rate should be steady at 100–120 compressions per minute to maintain consistent flow. For a single rescuer, the standard cycle is 30 compressions followed by 2 breaths, balancing chest compressions with ventilation.

The option that matches these three aspects—2-inch depth, 100–120/min, and a 30:2 compression-to-breath ratio—is the best choice.

Why the others aren’t suitable: one option uses only about 1 inch of depth and a slow rate with an unusual 15:2 ratio, which underperforms for adult perfusion. Another says there are no depth requirements and promotes continuous CPR, which isn’t aligned with current guidelines. The last option proposes too deep a depth (3 inches) and a rate that's too fast (140/min) with an uncommon ratio, increasing risk and deviating from recommended practice.