The APL valve is only used when the bag/ vent switch is set to what position?

The APL valve is only used when the bag/ vent switch is set to what position?

• A. Bag
• B. Vent
• C. Off
• D. On

Answer: (A)

The APL valve serves as a safety relief during manual ventilation. When you switch to bagging, you’re manually generating pressure with the reservoir bag, and the APL valve is allowed to vent excess gas to the scavenging system once the pressure hits the set limit. This prevents over-pressurization of the breathing circuit while you provide breaths. In contrast, during mechanical ventilation, the APL valve is effectively closed so the ventilator can deliver gas to the patient without losing it to scavenging. So the APL valve is used when the system is in the bagging position.

The APL valve serves as a safety relief during manual ventilation. When you switch to bagging, you’re manually generating pressure with the reservoir bag, and the APL valve is allowed to vent excess gas to the scavenging system once the pressure hits the set limit. This prevents over-pressurization of the breathing circuit while you provide breaths. In contrast, during mechanical ventilation, the APL valve is effectively closed so the ventilator can deliver gas to the patient without losing it to scavenging. So the APL valve is used when the system is in the bagging position.