SummarySeventy elderly males received lumbar epidural anaesthesia with 12 ml of 2% lidocaine containing fentanyl 50 lg. At the end of transurethral surgery, the washout group (n = 33) received an epidural bolus of 30 ml saline while the control group (n = 34) did not. Mean (SD) times to 1-grade (17.2 (11.9) vs 32.7 (11.3) min) and 2-grade regression (23.8 (12.2) vs 56.0 (23.9) min) of motor block, 3-dermatomal sensory regression (31.4 (11.6) vs 42.2 (14.4) min for cold and 30.8 (15.6) vs 40.6 (14.2) min for pinprick), and regression to S1 (57.7 (16.1) vs 76.2 (20.2) min for cold and 56.8 (17.3) vs 69.2 (16.2) min for pinprick) were significantly shorter in the washout group than the control group. There were no differences in postoperative pain scores and side effects between the two groups. We concluded that epidural washout facilitates regression of both motor and sensory block following epidural anaesthesia without reducing the postoperative analgesic benefit.