A. Incorrect response: See explanation B.
B. Correct response: The Aptaér heliox delivery system is available to deliver heliox with NPPV. It uses a premixed blend of heliox from a source gas cylinder and it delivers to a spontaneously breathing patient through a sealed face mask. The Aptaér enables the therapist to adjust the level of pressure support (3 to 20 cm H2O), trigger sensitivity (0.1 to 1.5 cm H2O), rise time, and cycle sensitivity (5% to 75% of peak inspiratory flow). It incorporates a vibrating mesh nebulizer, but does not include an O2 blender or PEEP capabilities.
C. Incorrect response: See explanation B.
D. Incorrect response: See explanation B.