In the scenario of auto-PEEP with inability to trigger, the recommended adjustment is to...?

• A. Increase CPAP to 8 cm H2O
• B. Decrease CPAP
• C. Increase tidal volume
• D. Increase trigger sensitivity

Answer: (A)

Auto-PEEP raises the end-expiratory pressure inside the lungs, so the patient must generate enough inspiratory effort to overcome that intrinsic pressure before the ventilator senses a trigger and begins a new breath. The quickest way to improve triggering is to raise the external PEEP (CPAP) to match or slightly exceed the intrinsic PEEP. By increasing CPAP to 8 cm H2O, the baseline airway pressure is raised to balance the auto-PEEP, making it easier for the patient’s effort to reach the trigger threshold and initiate a breath. Lowering CPAP would deepen the mismatch and worsen triggering; increasing tidal volume doesn’t address the triggering mechanism and can worsen lung injury; increasing trigger sensitivity can help temporarily but risks auto-triggering and doesn’t fix the underlying problem of air trapping.