An assembly structured to inflate a retaining or pressure cuff of a medical device including of the type associated with an artificial airway tube such as an endotracheal tube and/or tracheostomy tube and concurrently monitor pressure therein including a casing having a pressure chamber on its interior. A pump assembly is movably connected to the casing and structured to force fluid flow to the retaining cuff, for inflation, through said pressure chamber. An indicator member is disposed within the casing and is visually accessible through the casing window, wherein the indicator member is variably positionable dependent on and indicative of existing pressure within the retaining cuff. The existing pressure within the pressure chamber is substantially equivalent to that within the retaining cuff thereby facilitating the variable position of the indicator member to be indicative of pressure within the retaining cuff. A junction may be disposed in interconnecting relation between the casing and an inflation lumen to the retaining cuff and is structured to allow disconnection between the casing and the lumen but prevent reconnection thereto.