During bag-mask ventilation, what finding most strongly indicates effective ventilation?

• A. The mask is perfectly sealed with no air escape.
• B. The patient remains tachycardic.
• C. The oxygen saturation fails to improve.
• D. Adequate chest rise.

Answer: (D)

During bag-mask ventilation, the most reliable sign that ventilation is effective is adequate chest rise with each breath. Visible, symmetrical chest expansion shows that the air you’re delivering is entering the lungs and providing tidal volume, meaning the airway is open, the mask seal is functioning, and your technique is delivering ventilation to the alveoli. Other signs are less definitive: a perfect mask seal with no air escape doesn’t guarantee ventilation if there’s an airway obstruction or insufficient tidal volume; tachycardia can occur for many reasons and doesn’t directly measure ventilation; oxygen saturation may not improve immediately and can lag behind actual ventilation. So, watching for consistent chest rise is the best real-time indicator that your ventilation is effective.