What best describes a bag-valve-mask (BVM) during resuscitation?

• A. A device that provides continuous oxygen at 5 L/min
• B. A device used to ventilate a patient; delivers about 15 L/min, nearly 100% oxygen, about one breath every 6 seconds
• C. A device used to monitor blood pressure
• D. A device used to measure end-tidal CO2

Answer: (B)

A bag-valve-mask is a manual ventilation device used during resuscitation to ventilate a patient who isn’t breathing adequately. When connected to oxygen with a reservoir and the bag is squeezed, it delivers gas at high flow and a very high oxygen concentration—nearly 100% oxygen when set up correctly. The typical ventilation rate during CPR is about one breath every six seconds (roughly 10 breaths per minute), which aligns with delivering breaths while chest compressions continue. This device’s primary role is providing ventilation and oxygenation, not monitoring blood pressure or measuring end-tidal CO2 (capnography is a separate tool used to assess ventilation effectiveness). The description of continuous oxygen at 5 L/min fits other oxygen-delivery methods, not the BVM.