What is the primary function of a Bag-Valve-Mask (BVM) in emergency care?

The primary function of a Bag-Valve-Mask (BVM) in emergency care is to provide positive pressure ventilation. In situations where a patient is unable to breathe adequately on their own or has suffered respiratory failure, the BVM allows an advanced EMT to effectively ventilate the lungs by using a hand-held bag coupled with a facial mask. This ensures that oxygen can be delivered directly into the airway, helping to maintain adequate oxygenation of vital organs.

Using a BVM is particularly critical in emergencies where rapid interventions are necessary to restore normal breathing. This device creates a seal over the patient's face, allowing the EMT to manually squeeze the bag, pushing air, or supplemental oxygen, into the lungs. The ability to provide assistance in ventilation effectively transforms the management of respiratory emergencies and is a vital skill in prehospital care settings.

The other choices refer to different medical functions that do not pertain to the BVM: measuring blood pressure involves a sphygmomanometer; administering medication requires different delivery devices; and delivering high-flow oxygen generally uses devices like non-rebreather masks or nasal cannulas, which are not designed for positive pressure ventilation.