Which of the following is a common cause of poor BVM ventilation?

• A. Airway obstruction
• B. Adequate mask seal
• C. Correct head position
• D. Sufficient oxygen flow

Answer: (C)

A key factor in effective BVM ventilation is keeping the airway open and easy to seal. When the head isn’t in the right position, the airway axis isn’t aligned, and the tongue and soft tissues can fall back and partially or completely obstruct the airway. That makes it hard for air to move in and out even if you’ve got the mask on correctly. Getting the head into a neutral, properly aligned position (and using a jaw-thrust if spinal injury is suspected) straightens the airway, improves the space behind the tongue, and allows a better mask seal. With the airway open and the seal solid, ventilation improves quickly.

Other factors like a poor mask seal or insufficient oxygen flow can also cause poor ventilation, but they reflect separate issues—whereas head position directly influences airway patency and the ability to ventilate when using a bag-valve-mask.