“Ureteric Visualization: Vitamin B Vs 5% Dextrose in Water”
Background: The risk of ureteric injury at the time of pelvic reconstructive surgery can be as high as 3% and the American College of Obstetricians and Gynecologists has stated that intraoperative cystoscopy should be done after all such procedures. Intravenous indigo carmine was routinely given during surgery to colour the urine bright blue and allow for assessment of ureteric integrity. In 2014, indigo carmine was no longer available worldwide and since then, surgeons have been searching for suitable alternatives. Vitamin B is a water soluble vitamin that colours the urine bright yellow and can be given immediately before surgery to help with ureteric visualization. Alternatively, 5% dextrose in water (D5W) can be used as the instillation fluid during cystoscopy to allow for urine jet visualization due to the difference in fluid viscosity. Both agents have been shown to be better than instillation with normal saline and are affordable and accessible in Canada. Objective: To identify which agent is superior for intraoperative ureteric visualization at the time of cystoscopy by determining the difference in detection rate of both ureteric jets using either preoperative oral vitamin B or intraoperative cystoscopic distension with D5W. Methods: This study will be a three-site (Mount Sinai Hospital, Sunnybrook Health Sciences Centre, Women's College Hospital), double-blinded, randomized control trial whereby female patients undergoing pelvic reconstructive surgery will be randomized to receive either preoperative vitamin B or intraoperative D5W cystoscopic instillation fluid. Parameters measured during surgery will include whether both ureteric jets were seen, time to visualization of both ureters, colour of jets, and surgeon satisfaction. Patients will also be seen at one week after surgery to assess for urinary tract infection. Sample size calculation based on previous studies demonstrated a need for 125 patients per study arm. Anticipated Clinical Significance: The findings of this study will be relevant to all surgeons performing intraoperative cystoscopy where ureteric visualization is required. The investigators believe the outcome of this study will help make cystoscopy shorter and more efficient for surgeons who often feel the pressure of time constraints within the operating room setting. In turn, decreasing the time of cystoscopy may reduce operating times which will benefit both the patient and hospital.
Vitamin B (riboflavin, vitamin B2)
Vitamin B is a natural health product approved as a colouring agent.
5% Dextrose in Water (D5W)
5% Dextrose in Water is an irrigation/instillation fluid, commonly used in intravenous lines.
Optimal Ureteric Visualization At the Time of Pelvic Reconstructive Surgery: Vitamin B Versus 5% Dextrose in Water