Basic Life Support (BLS) Practice Exam 2026 - Free BLS Practice Questions and Study Guide

The recommended CPR technique for a 4-month-old infant is to use the encircling thumbs technique with correct ventilation. This method involves placing both thumbs on the center of the infant's chest while supporting the back with the fingers, creating a secure grip. This technique allows for adequate depth of compressions, which should be approximately 1.5 inches deep, and it is more suited for the small size and vulnerability of infants.

Additionally, when performing rescue breaths, it is important to ensure that the infant's airway is open by tilting the head back slightly. The breaths should be gentle, covering the infant's mouth and nose appropriately, providing just enough air to see the chest rise. The combination of high-quality compressions and effective ventilations is crucial for increasing the chances of survival in an infant experiencing cardiac arrest.

Other techniques may not provide the necessary effectiveness or safety for an infant of this age. For instance, using one hand might not deliver sufficient depth; standing while delivering compressions can lead to ineffectiveness due to poor positioning, and compressing on an elevated surface may not be safe or appropriate for maintaining proper technique. Thus, understanding and applying the encircling thumbs technique is essential for performing CPR correctly on an infant.