A flexible pneumostoma management device maintains the patency of a pneumostoma while controlling the flow of material through the pneumostoma. The pneumostoma management device includes a pneumostoma vent having a tube which enters the pneumostoma to allow gases to escape the lung, a flange and a filter/valve to control flow of materials through the tube. The flange is a thin flexible patch comprises of multiple thin layers of materials and which conforms and attaches to the chest of the patient. The flange includes a filter, a protective outer layer and an inner hydrocolloid layer. The flange secures the tube in position in the pneumostoma. An indicator responsive to gases exiting the pneumostoma is integrated into the device and provides and external indicia of the patency and efficacy of the pneumostoma.