Abstract: The invention relates to a surgical device for use in operative substitution or replacement for a damaged or malformed body conduit or blood vessel, an example being an aortic aneurysm. One preferred embodiment includes a tubular body having open-end portions to provide a passageway. The wall of the body when inflated includes an annular chamber. Surrounding the body is an outer chamber of a flexible sleeve member. A probe is provided which extends forwardly of the leading end of the body, the probe providing sampling apertures to allow monitoring of body fluid flow when the device is in place. Further tubes permit inflation of the chambers. This device is suitable for insertion through the femoral artery.