Basic Life Support (BLS) Practice Exam 2025 - Free BLS Practice Questions and Study Guide

The appropriate chest compression depth for an infant is one third of the anteroposterior diameter of the chest, which is approximately 4 cm (about 1.5 inches). This depth is crucial as it ensures that compressions are effective in creating sufficient blood flow during cardiopulmonary resuscitation (CPR). Infants have a more compliant chest wall compared to adults, so the recommended depth is shallower.

In terms of compressions, this depth allows for adequate circulation to vital organs, particularly the heart and brain, which are sensitive to prolonged periods without oxygen. Effective chest compressions are a key component of BLS, especially when managing cardiac arrest in infants. It's important to maintain the correct depth to maximize the chances of survival and recovery.

The other options either suggest depths that are ineffectively shallow or excessively deep for the infant's anatomy. Adhering to the guidance around one third of the chest depth provides a balance of safety and effectiveness necessary for infant CPR.