A patient receiving continuous mandatory ventilation in the assist-control mode develops auto-PEEP. Which of the following changes in ventilatory patterns would you consider to minimize the effects of auto-PEEP in this patient?
1) Decreasing the rate or increasing V_T
2) Using low-rate synchronized intermittent mandatory ventilation
3) Decreasing the peak inspiratory flow
4) Lowering the V_T and letting the PaCO₂ rise

Question

Quizplus · Accepted Answer

Auto-PEEP (positive end-expiratory pressure) occurs when air gets trapped in the lungs during mechanical ventilation, often due to insufficient expiratory time. To minimize its effects, strategies include decreasing the ventilatory rate or increasing the time for expiration (1), using low-rate synchronized intermittent mandatory ventilation to allow more time for expiration (2), and lowering the tidal volume to reduce the amount of air entering the lungs each cycle, thereby allowing CO2 levels to rise slightly if necessary for better ventilation (4). Decreasing the peak inspiratory flow (3) does not directly address the issue of insufficient expiratory time and is not a recommended strategy for minimizing auto-PEEP.

A Patient Receiving Continuous Mandatory Ventilation in the Assist-Control Mode