A compound sheath comprising: an endoscopic channel arranged for accepting an elongated endoscopic imaging device； a parallel use channel arranged for accepting a catheter-based tool, and a multi-channel hub that couples to the proximal end of the parallel use channel comprising: a rinse port that couples to a fluid reservoir device that injects fluid； a withdrawal port that couples to a vacuum forming device that removes fluid； a tool port for passing a catheter-based tool； wherein the multi-channel hub establishes a fluid channel for fluid communication between the parallel use channel and the rinse port or the withdrawal port, and a mechanical channel for passing therethrough a catheter-based tool between the parallel use channel and the tool port such that fluid from the rinse port or the withdrawal port and the catheter-based tool of the tool port are simultaneously passing all along the parallel use channel.
