Please confirm that an ethics committee approval has been applied for or granted: Yes: I’m uploading the Ethics Committee Approval as a PDF file with this abstract submission

Background and Aims Catheter-related bladder discomfort (CRBD) is characterized by a burning sensation at the urethra, an urgent need to void, frequent urination, and painful discomfort in the suprapubic area following the insertion of an indwelling urinary catheter. This study aims to assess the effectiveness of pre-emptive oral melatonin in reducing early postoperative pain and preventing CRBD in patients undergoing transurethral resection of the prostate (TURP) surgery during the immediate postoperative period.

Methods Following ethical clearance and written informed consent, 70 ASA 1 or 2 patients undergoing TURP surgery under spinal anaesthesia were included. Exclusion criteria were refusal, liver or renal failure, or chronic analgesic use. Patients were randomly assigned into two groups of 35 each. Group M received 5 mg of oral melatonin one day before and on the morning of surgery. Group D received an oral vitamin C placebo at the same time. The primary outcome was pain using the visual analogue scale (VAS) at 0, 2, 8, 12, and 24 hours post-surgery. Secondary outcomes were the assessment of the incidence and severity of CRBD using a four-point severity scale.

Results Group M had significantly reduced VAS scores at all time points compared to group D(p=0.002 at 0 hr, p=0.001 at 2,8,12, and 24 hrs ). The incidence and severity of CRBD were also significantly lower in Group M at all intervals (p<0.05).

Conclusions Pre-emptive administration of melatonin effectively reduces the immediate post-operative pain, incidence and severity of CRBD in patients undergoing TURB surgery under spinal anaesthesia.