Which ventilator adjustment is used to prevent alveolar collapse at the end of expiration in ARDS?

Which ventilator adjustment is used to prevent alveolar collapse at the end of expiration in ARDS?

• A. Increase tidal volume
• B. Increase respiratory rate
• C. High FiO2
• D. Positive end-expiratory pressure

Answer: (D)

In ARDS, preventing alveolar collapse at the end of expiration hinges on keeping the airways and alveoli open as you exhale. The adjustment that does this is applying positive end-expiratory pressure (PEEP), which maintains a positive pressure in the lungs at the end of expiration. This helps keep alveoli recruited, reduces cyclic collapse, and improves oxygenation by lowering intrapulmonary shunt. Other options don’t address the end-expiratory patency as directly. Increasing tidal volume can raise the risk of lung injury (volutrauma) without reliably preventing alveolar collapse. Increasing the respiratory rate by itself doesn’t maintain alveolar openness and can worsen ventilation-perfusion mismatch or auto-PEEP. High FiO2 improves oxygen content but doesn’t keep alveoli open at the end of expiration.

In ARDS, preventing alveolar collapse at the end of expiration hinges on keeping the airways and alveoli open as you exhale. The adjustment that does this is applying positive end-expiratory pressure (PEEP), which maintains a positive pressure in the lungs at the end of expiration. This helps keep alveoli recruited, reduces cyclic collapse, and improves oxygenation by lowering intrapulmonary shunt.

Other options don’t address the end-expiratory patency as directly. Increasing tidal volume can raise the risk of lung injury (volutrauma) without reliably preventing alveolar collapse. Increasing the respiratory rate by itself doesn’t maintain alveolar openness and can worsen ventilation-perfusion mismatch or auto-PEEP. High FiO2 improves oxygen content but doesn’t keep alveoli open at the end of expiration.