The Efficacy of Tolterodine for Prevention of Catheter- Related Bladder Discomfort: A Prospective, Randomized, Placebo-Controlled, Double-Blind Study Anil Agarwal, MD*, Mehdi Raza, MD*, Vinay Singhal, MD*, Sanjay Dhiraaj, MD*, Rakesh Kapoor, MS, McH†, Aneesh Srivastava, MS, McH†, Devendra Gupta, MD*, Prabhat K. Singh, MD*, Chandra Kant Pandey, MD*, and Uttam Singh, PhD‡ Departments of *Anesthesia, †Surgical Urology, and ‡Biostatistics, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India Bladder discomfort secondary to an indwelling urinary catheter is distressing, particularly for patients awaken- ing from anesthesia. We sought to discover the inci- dence and severity of bladder discomfort in patients who were catheterized intraoperatively and to evaluate the efficacy of tolterodine, a pure muscarinic receptor antagonist, in preventing this. Two-hundred-fifteen consecutive adult patients, ASA physical status I and II, either sex, undergoing urologic surgery requiring blad- der catheterization were enrolled. Group C (control, n = 165) received placebo and group T (tolterodine, n = 50) received tolterodine 2 mg. Drugs were administered orally 1 h before surgery. After induction of anesthesia, patients were catheterized with a 16F Foley catheter and the balloon was inflated with 10 mL of normal sa- line. In the postanesthesia care unit, bladder discomfort was assessed on arrival (0), 1, 2 and 6 h. Severity of blad- der discomfort was graded as mild, moderate, and se- vere. Bladder discomfort observed in group C was 55% (91 of 165). Tolterodine reduced both the incidence 36% (18 of 50) and severity of bladder discomfort (P  0.05). (Anesth Analg 2005;101:1065–7) Bladder discomfort secondary to an indwelling uri- nary catheter is very distressing and this is more so in patients awakening from anesthesia. It is not unusual to find patients catheterized during anesthesia com- plaining of an urge to void in the postoperative period because of catheter-related bladder irritation. Various treatments have been tried with varying degrees of success for managing this troublesome side effect (1). Tolterodine, a competitive muscarinic receptor antag- onist, has been used successfully to treat overactive bladder (urgency, urge incontinence, and micturition frequency) (2). The incidence and severity of bladder discomfort secondary to an indwelling urinary catheter has not been reported. We conducted this study to evaluate the incidence and severity of bladder discomfort in patients who were catheterized intraoperatively and to evaluate the efficacy of tolterodine in attenuating this discomfort. Methods After approval from the Institute’s ethics committee and written informed consent from the patients, we initially conducted a pilot study of 50 surgical patients who were catheterized intraoperatively and observed that 26 (52%) of the patients complained of bladder discomfort in the postoperative period. Assuming that the incidence of bladder discomfort would decrease to 30% after tolterodine administration, we enrolled 165 patients in the control group (group C) and 50 in the tolterodine group (group T) for the results to be sta- tistically significant with a power of 80% and  = 0.05. Therefore, 215 consecutive adults, ASA physical status I and II patients of either sex, undergoing elective endoscopic or open urologic surgery for the kidney and ureter and requiring catheterization were in- cluded in this prospective, randomized, double-blind, placebo-controlled study. Patients were randomized with the help of a computer-generated table of random numbers into two groups. Group C (n = 165) received placebo and group T (n = 50) received tolterodine 2 mg (Detrusitol, Pharmacia Italia S.p.A). Both drugs were given orally 1 h before induction of anesthesia. Exclusion criteria Accepted for publication March 30, 2005. Address correspondence and reprint request to Dr. Anil Agarwal, Type IV/48, SGPGIMS, Lucknow 226 014, India. Address e-mail to aagarwal@sgpgi.ac.in. DOI: 10.1213/01.ane.0000167775.46192.e9 ©2005 by the International Anesthesia Research Society 0003-2999/05 Anesth Analg 2005;101:1065–7 1065