What is the recommended chest compression depth for an adult and what must you ensure after each compression?

• A. At least 1 inch with partial recoil
• B. 2-3 inches with partial recoil
• C. At least 2 inches (5 cm) with complete chest recoil after each compression
• D. 3-4 inches with no recoil

Answer: (C)

The main idea is that effective adult CPR requires both enough depth to push blood out of the heart and complete chest recoil to allow the heart to refill between compressions. For an adult, compress to at least 2 inches (about 5 cm) with each push. After releasing, let the chest fully rebound so there is complete chest recoil after every compression. This full recoil is crucial because it permits venous return to the heart and helps maintain coronary and cerebral perfusion pressure. If the depth is too shallow, the blood flow generated is insufficient. If there’s incomplete or no recoil, the heart doesn’t fill properly between compressions, reducing effectiveness.