The present system (10) comprises a subject interface (22), a segmenter (12), a loosener (14), sensors (18), and computer processors (28). The segmenter is configured to selectively control gas flow through the subject interface to provide high amplitude pressure oscillations (44) during exhalation such that the high amplitude pressure oscillations aid cough productivity in the subject. The loosener controls gas flow through the subject interface to provide low amplitude pressure oscillations (43, 63) during inhalation (48, 68) and exhalation (49) such that the low amplitude pressure oscillations loosen respiratory secretions. The computer processors detect trigger events based on the output signals such that the one or more trigger events include a loosening trigger event and a segmenting trigger event (66) and responsive to detecting the loosening trigger event, control the loosener to provide the low amplitude pressure oscillations, and, responsive to detecting the segmenting trigger event, control the segmenter to provide the high amplitude pressure oscillations.
