Effect of intrathecal tramadol administration on postoperative pain after transurethral resection of prostate.

BACKGROUND Tramadol administered epidurally has been demonstrated to decrease postoperative analgesic requirements. However, its effect on postoperative analgesia after intrathecal administration has not yet been studied. In this double-blind, placebo-controlled study, the effect of intrathecal tramadol administration on pain control after transurethral resection of the prostate (TURP) was studied. METHODS Sixty-four patients undergoing TURP were randomized to receive bupivacaine 0.5% 3 ml intrathecally premixed with either tramadol 25 mg or saline 0.5 ml. After operation, morphine 5 mg i.m. every 3 h was administered as needed for analgesia. Postoperative morphine requirements, visual analogue scale for pain at rest (VAS) and sedation scores, times to first analgesic and hospital lengths of stay were recorded by a blinded observer. RESULTS There were no differences between the groups with regard to postoperative morphine requirements (mean (SD): 10.6 (7.9) vs 9.1 (5.5) mg, P=0.38), VAS (1.6 (1.2) vs 1.2 (0.8), P=0.18) and sedation scores (1.2 (0.3) vs 1.2 (0.2), P=0.89). Times to first analgesic (6.3 (6.3) vs 7.6 (6.2) h, P=0.42) and length of hospital stay (4.7 (2.8) vs 4.4 (2.2) days, P=0.66) were similar in the two groups. CONCLUSION Intrathecal tramadol was not different from saline in its effect on postoperative morphine requirements after TURP.