Prophylactic heparin does not increase clinically significant bleeding following transurethral resection of a bladder tumor.

Introduction: Transurethral resection of bladder tumor (TURBT) is a high bleeding risk procedure due to resection over a mucosal surface and is often performed in patients with risk factors for venous thromboembolism (VTE). Limited data exist to inform the risks and benefits of prophylactic heparin before TURBT. We sought to assess whether preoperative heparin was associated with clinically significant bleeding after TURBT.

Methods: We retrospectively identified 583 consecutive patients who underwent TURBT between Jan 1, 2021 and April 30, 2023. In April 2022 we began routinely administering 5,000 units of subcutaneous heparin at anesthesia induction during TURBT. The primary outcome was clinically significant bleeding within 30 days of TURBT, defined as reoperation for clot evacuation/fulguration, clot retention, blood transfusion, and/or continuous bladder irrigation.

Results: Among 583 patients, 220 (38%) received preoperative heparin and 363 (62%) did not. Twenty-five patients experienced a bleeding event, including 6 (2.7%) in the heparin group and 19 (5.2%) in the no heparin group (P = 0.25). After adjusting for sex and tumor size, heparin was not significantly associated with clinically significant bleeding (adjOR 0.51, 95% CI, 0.18-1.2, P = 0.16). Three patients (0.5%) experienced a 30-day VTE, including 1 (0.5%) in the heparin group and 2 (0.6%) in the group without heparin (P = 0.9).

Conclusion: We did not observe a statistically significant difference in the rate of clinically significant bleeding within 30 days of TURBT between patients treated with and without preoperative heparin, suggesting that preoperative heparin can be considered among patients at high risk of postoperative VTE.