During two-rescuer ventilation, how long should the second rescuer squeeze the bag-mask device?

The recommended duration for squeezing the bag-mask device during two-rescuer ventilation is typically around 1 second per breath. This timing allows for effective ventilation without over-inflating the lungs, which can lead to complications such as barotrauma or poor ventilation.

When delivering breaths, it is essential to ensure that the positive pressure ventilation is not too forceful or prolonged. A 1-second squeeze allows the lungs to inflate adequately while providing enough time for the rescuer to evaluate the rise and fall of the chest, confirming that ventilation is occurring effectively. Following this, the second rescuer should allow for an adequate pause to enable the patient to exhale before delivering the next breath.

This approach prioritizes both effectiveness in oxygen delivery and the minimization of potential complications associated with artificial ventilation. The correct answer underscores the importance of precise timing in delivering rescue breathing during a critical emergency.