Why must you allow full chest recoil during CPR?

Allowing full chest recoil during CPR is crucial because it facilitates blood flow back to the heart between compressions. When the chest fully recoils after each compression, it creates negative pressure in the thoracic cavity, effectively drawing blood back into the heart. This process is vital for maintaining adequate circulation during CPR, as it helps to maximize the volume of blood that can be pumped during each subsequent compression. Adequate blood return to the heart is essential to ensure that if and when the heart starts beating again, it is filled with enough blood to be effective in pumping oxygenated blood to the rest of the body.

While there are other considerations in performing CPR, such as minimizing the risk of injury to the ribs and preventing the rescuer from tiring quickly, the primary physiological reason for allowing full chest recoil focuses on blood flow dynamics and the effectiveness of resuscitation efforts.