To keep irrigation outflow pressure constant even when an amount of physiological saline within a bottle reduces during an operation; and to allow one or more operators to drain the physiological saline to areas to be operated simultaneously.

A pressurization tube 12 and at least one or more irrigation tubes 10 and 11 are connected to a cap 3 of a pressure bottle 2. Compressed air 20 subjected to pressure adjustment is supplied to a pressure bottle 1 through the pressurization tube 12 having an air sterilization filter 13 so as to pressurize the inside of the bottle by a predetermined air pressure. By doing so, a plurality of operators can drain physiological saline 7 through the irrigation tubes 10 and 11. A flow amount can be adjusted by the operators by operating valve means 30 at hand.