Abstract: Apparatus for the distention and irrigation of a saphenous vein which is being tested prior to use as a coronary or peripheral bypass graft includes a specially-configured cannula for insertion into the vein, and a pressure-limiting device having a resilient membrane reservoir which limits the hydrostatic pressure delivered to the vein to a predetermined level. The device is connected between the cannula inserted into the vein and a syringe filled with irrigation fluid. As fluid is delivered under pressure from the syringe, the membrane reservoir fills with fluid and inflates within a specified range of pressures so that if excessive force is applied to the syringe, the membrane inflates, and the pressure transmitted to the vein cannot exceed a predetermined maximum pressure. A stopcock connected between the syringe and the membrane allows the membrane to be pressurized with the contents of the syringe.

Abstract: A cannula used in the distention and irrigation of a saphenous vein which is being tested prior to use as a coronary or peripheral bypass graft includes a tapered and beveled tip which allows easy insertion into the vein, and a sloping shoulder just proximal to the tip which provides a convenient site for firmly securing the vein to the cannula with a ligature. The cannula can be utilized in a distention and irrigation apparatus which includes a pressure limiting device having a resilient membrane reservoir which limits static pressure delivered to the vein to a predetermined level. The device is connected between the cannula of the present invention and a syringe filled with irrigation fluid.