Abstract: A flushing instrument or irrigator for surgical purposes comprises a stem 11 having an inlet end 29 adapted for connection to a flushing fluid supply line 13 and a discharge end 12. A fluid supply passage 16, 17, 18, 24, 19, 20, 21 is able to convey flushing fluid from the inlet end 29 to the discharge end 12. A valve 14 with a longitudinally movable slider 15 is movable between first and second abutments 22 and 23 from a retracted position in which it blocks the supply passage to an advanced position in which the supply passage is open for the transfer of flushing fluid to the discharge end of the stem and then via a cannula 38 to the site of the operation. In one embodiment the cannula 38 is also provided with a drainage duct 50 leading to a drainage passage 49 in the stem 11 in order to drain fluid away from the site of the operation. The drainage passage can be blocked by a transversely disposed slide valve 31.