How is auto-PEEP quantified during an expiratory hold?

How is auto-PEEP quantified during an expiratory hold?

• A. The plateau pressure
• B. End-expiratory pressure during the hold that exceeds the set PEEP
• C. The peak inspiratory flow
• D. The mean airway pressure

Answer: (B)

Auto-PEEP is the intrinsic pressure that remains in the lungs at the end of expiration due to incomplete emptying. To quantify it, you use an expiratory hold and look at the end-expiratory airway pressure. If that end-expiratory pressure is higher than the ventilator’s set PEEP, the difference is the auto-PEEP. For example, with a set PEEP of 8 cm H2O, an end-expiratory pressure of 12 cm H2O during the hold means auto-PEEP is 4 cm H2O. This method isolates the trapped gas at the end of expiration. Plateau pressure is measured during an inspiratory hold to reflect alveolar pressure at end inspiration, not intrinsic PEEP. Peak inspiratory flow relates to how quickly air is delivered during inspiration, not the amount of trapped air. Mean airway pressure is the average pressure over the whole breath, not the specific end-expiratory overflow that defines auto-PEEP.

Auto-PEEP is the intrinsic pressure that remains in the lungs at the end of expiration due to incomplete emptying. To quantify it, you use an expiratory hold and look at the end-expiratory airway pressure. If that end-expiratory pressure is higher than the ventilator’s set PEEP, the difference is the auto-PEEP. For example, with a set PEEP of 8 cm H2O, an end-expiratory pressure of 12 cm H2O during the hold means auto-PEEP is 4 cm H2O. This method isolates the trapped gas at the end of expiration.

Plateau pressure is measured during an inspiratory hold to reflect alveolar pressure at end inspiration, not intrinsic PEEP. Peak inspiratory flow relates to how quickly air is delivered during inspiration, not the amount of trapped air. Mean airway pressure is the average pressure over the whole breath, not the specific end-expiratory overflow that defines auto-PEEP.