To place the anesthesia machine in bag-mode ready state, which control should be set?

• A. Vaporizers on
• B. APL valve completely open
• C. Selector switch to bag
• D. Flowmeters set to maximum

Answer: (C)

The key idea is routing gas to the reservoir bag for manual ventilation. Putting the selector switch in the bag position directs fresh gas flow into the bag and the breathing circuit, inflating the bag so you can manually ventilate. This makes the system ready for bagging without delivering anesthesia or venting to scavenging through the circuit in an uncontrolled way.

Other options don’t set this path: turning vaporizers on isn’t about enabling manual ventilation, fully opening the APL valve mainly affects pressure relief and leakage rather than directing flow to the bag, and setting flowmeters to maximum changes flow rate but not the route to the reservoir bag.