An adjustable airway pressure system is provided. The system may include a cap and a canister. The cap may include a substantially hollow conduit having indicia indicative of a plurality of airway pressure values and adapted to receive and output exhaled gas. The conduit may have screw threads on an exterior surface of the conduit. The cap may also include an adjust collar circumscribing the conduit and having an interior surface with a second plurality of screw threads. The second plurality of screw threads may couple and be complementary to the first plurality of screw threads such that a rotation of the adjust collar causes the conduit to move in a substantially vertical direction. The conduit may be adapted to be adjusted to heights along a continuum. The canister may contain liquid and receive the conduit such that the received exhaled gas is output from the conduit into the liquid.
