The therapist is about to ventilate a neonate with HFJV. She has different injectors and can place the one she selects in a variety of locations. Where should the therapist position the injector in relation to the patient's airway to minimize the patient's functional dead space?

A. at the external opening of the ETT
B. at the distal tip of the ETT
C. in the breathing circuit of the ventilator
D. beyond the distal tip of the ETT

ANS: D
A. Incorrect response: See explanation D.
B. Incorrect response: See explanation D.
C. Incorrect response: See explanation D.
D. Correct response: High-frequency jets operate on the principle of a nozzle or an injector that creates a high velocity jet of gas directed into the patient's lungs. These injectors are usually 1 to 3 cm in diameter, and can be placed in one of several locations in the ventilator circuit and/or patient airway. Generally the further down the airway the injector is placed, the less is the patient's functional dead space.