Evaluation of intra-operative tramadol for prevention of catheter-related bladder discomfort: a prospective, randomized, double-blind study

Background. Catheter-related bladder discomfort (CRBD) is defined as an urge to void or discomfort in the supra-pubic region; reported postoperatively in patients who have had urinary catheterization intra-operatively. We have evaluated tramadol, a centrally acting opioid analgesic with muscarinic receptor antagonist properties for prevention of CRBD. Methods. Fifty-four adults (18-60 yr), ASA physical status I and II of either sex, undergoing elective percutaneous nephro-lithomy were randomly divided into two groups of 27 each. Control (C) group received normal saline (NS; 2 ml), whereas Tramadol (T) group received tramadol 1.5 mg kg(-1). All medications were diluted in 2 ml NS and administered 30 min before extubation. Intra-operatively, urinary catherization was performed with a 16 Fr Foley's catheter, and the balloon was inflated with 10 ml distilled water. The CRBD was assessed at 0, 1, 2, and 6 h after patient's arrival in the post-anaesthesia care unit along with total postoperative fentanyl requirement. Severity of CRBD was graded as none, mild, moderate and severe. Data were analysed by one-way anova, Z-test, and Fisher's exact test. P < 0.05 was considered significant. Results. Incidence and severity of CRBD was reduced in T group compared with C group at all time points (P < 0.05). Postoperative pain as assessed by visual analogue scale and total postoperative fentanyl requirement (mu g kg(-1)) was also reduced in the T group [176 (sd 26.5)] compared with C group [210 (34.6)] (P < 0.05). Conclusions. Tramadol 1.5 mg kg(-1) administered i.v. 30 min before extubation decreases the incidence and severity of CRBD and postoperative fentanyl requirement.