Tetracaine hydrochloride gel delays and reduces catheter-related bladder discomfort after transurethral resection: a randomized controlled trial

Background Catheter-related bladder discomfort (CRBD) results from involuntary bladder contractions triggered by both the indwelling urinary catheter and surgical trauma during transurethral resection. Systemic analgesics and anticholinergics are often used but carry risks of side effects. Topical anesthetics like tetracaine hydrochloride gel offer a potential targeted approach, but their efficacy in delaying and reducing CRBD remains unclear. Methods In this randomized, single-blind study, patients undergoing transurethral resection were allocated to the tetracaine gel group ( n = 65) or the lubricant control group ( n = 65). Before catheter insertion, three g of tetracaine gel or standard lubricant was evenly applied to the catheter surface. The primary outcome was the time to first-reported moderate-to-severe CRBD after tracheal extubation. Secondary outcomes included the incidence of new-onset moderate and severe CRBD at specified intervals, as well as the patient satisfaction, postoperative pain scores, analgesic requirements, and adverse events. The incidence of moderate-to-severe CRBD stratified by age and procedure type was also analyzed. Results The time to first-reported moderate-to-severe CRBD was significantly longer in the tetracaine gel group compared to the control group (30 [10.0–61.3] min vs. 5 [4.8–10.0] min, p < 0.001) among patients who developed this event. The incidence of new-onset moderate-to-severe CRBD was significantly lower in the tetracaine gel group within 30 min (15 [23.1%] vs. 43 [66.2%]; RR = 0.153, 95% CI [0.071–0.332]; p < 0.001) and over the total 24 hours assessment period (30 [46.2%] vs. 46 [70.8%]; RR = 0.354, 95% CI [0.172–0.730]; p = 0.004). A transient increase in incidence was noted in the tetracaine group between 30–120 min (11 [16.9%] vs. 2 [3.1%]; RR = 6.417, 95% CI [1.362–30.228]; p = 0.016). The non-significant interaction test indicates that the effect magnitude of tetracaine gel did not differ by age ( P for interaction = 0.392) or procedure type ( P for interaction = 0.883). Patient satisfaction at 6 hours was higher (6.7 ± 0.5 vs. 6.2 ± 0.8, p < 0.001), and postoperative pain scores were lower at all assessed time points. No significant differences were found in analgesic requirements, postoperative delirium, infections, or hospital stay. Conclusions Topical application of tetracaine gel to the urinary catheter effectively delays the onset and reduces the incidence of moderate-to-severe CRBD in the early postoperative period.