Which statement regarding the one-person bag-valve mask technique is correct?

• A. Adequate tidal volume is often difficult to achieve when one EMT is operating the bag-valve mask.
• B. The C-clamp method of holding the mask to the face is not effective when ventilating a patient with a bag-valve mask.
• C. The bag-valve mask delivers more tidal volume and a higher oxygen concentration than the mouth-to-mask technique.
• D. Bag-valve mask ventilations should be delivered every 2 seconds when the device is being operated by one person.

Answer: (A)

The key idea here is that when only one rescuer is using a bag-valve mask, maintaining a tight seal and delivering enough air with each squeeze is hard to sustain. A single EMT has to hold the mask securely, open the airway, and squeeze the bag with enough force to produce a adequate tidal volume, all at once. Fatigue, imperfect seal, or airway leakage often means you don’t ventilate enough air, so adequate tidal volume is commonly difficult to achieve in a one-person setup.

That’s why this statement is the best: it speaks to the practical limitation that a single rescuer faces during bag-valve-mask ventilation. The other points aren’t as central to the one-person scenario: using the C-E or C-clamp grip is a valid and effective technique to maintain a seal, so saying it isn’t effective isn’t accurate; a bag-valve mask can deliver greater tidal volume and FiO2 than mouth-to-mouth ventilation in general, which is true but not specifically about the one-person technique; and delivering breaths every 2 seconds is too fast for an adult patient—typical rates are about one breath every five seconds (roughly 10–12 breaths per minute).