Abstract: A bi-directional gas flow generation system (10), the system comprising: (a) a pressure generator (14) comprising an inlet (40) and an outlet (42), (b) a flow member (16) comprising an outlet port (50), an inlet port (52), a respiratory circuit port (54) and a flow path (60), (c) a first valve (18), (d) a second valve (20), and (e) a processor (24) configured to selectively control the first valve and the second valve to operate in (i) a first mode in which gas flows from the flow member inlet port (52) to the respiratory circuit port (54), thereby creating a positive pressure at the respiratory circuit port (54) to insufflate the subject; and (ii) a second mode in which gas flows from the respiratory circuit port (54) to the flow member outlet port (50), thereby facilitating gas flow out from the airway of the subject to exsufflate the subject.