Where are flowmeters located in the breathing circuit?

• A. Between expiratory and inspiratory limbs of the breathing circuit
• B. Between the gas source and the bulk bag
• C. At the patient end of the circuit
• D. After the Y-piece

Answer: (A)

Fresh gas flow is measured and adjusted on the inspiratory limb so the amount you set is exactly what reaches the patient. In a circle breathing system, the inspiratory and expiratory limbs meet near the patient at the Y-piece. The flowmeter sits on the inspiratory path, between the gas source and the patient, so the measured flow is the gas that will actually be inspired. This placement keeps the reading independent from the exhaled gas looping back through the expiratory limb and ensures accurate delivery of the set fresh gas flow. It’s not placed at the patient end, not after the Y-piece, and not simply somewhere between the gas source and the bulk bag.