What is the primary purpose of using a bag-valve mask (BVM) device?

The primary purpose of using a bag-valve mask (BVM) device is to provide positive pressure ventilation. This device is designed to assist or replace spontaneous breathing for patients who cannot ventilate adequately on their own. When the bag is squeezed, it forces air into the lungs, helping to ensure that the patient receives adequate oxygenation and ventilation, especially in emergencies such as respiratory failure or cardiac arrest.

While oxygen can be administered through the BVM when connected to an oxygen source, its primary function is related to ventilation. It is not intended for delivering medications or monitoring vital signs, which are functions served by other medical devices and procedures. The effectiveness of a BVM depends on proper sealing against the patient's face and adequate technique from the operator to deliver air effectively into the lungs.