The American College of Obstetricians and Gynecologists, under the auspices of the ACOG Committee on Educational Bulletins, has issued a report (ACOG Educational Bulletin No. 238) on the diagnosis and management of operative injuries of the urethra, bladder and ureters. According to the report, bladder or ureteral injuries occur in an estimated 1 percent of major gynecologic operations and cesarean sections, with 75 percent of the injuries associated with hysterectomy.
While most intraoperative lower urinary tract injuries occur in the absence of identified predisposing factors, contributing factors include limited exposure or visibility because of large pelvic masses, a pregnant uterus, hemorrhage, malignancy and inadequate incision, retraction and lighting. Conditions that may distort the anatomy, such as myomas, cancer, endometriosis, chronic inflammatory disease, previous pelvic surgery and radiation fibrosis, may also play a role. Some of these conditions may require dissection and surgical resection of portions of the ureter, bladder or urethra. Excision of the involved tissues may damage the blood and nerve supply.
The report states that lower urinary tract injuries may be detected by intravenous administration of 5 mL of indigo carmine, allowing the bladder to be filled with blue-dyed urine. Ureteral or bladder leaks allow spillage of dye into the pelvis. Absence of dye in the bladder may indicate bilateral ureteral obstruction. Dye in the bladder, however, does not exclude unilateral or partial ureteral obstruction.
Total bilateral ureteral obstruction is manifested by anuria and rising blood urea nitrogen and creatinine levels. Partial or complete ureteral transection may present as clear vaginal discharge or abdominal distention, often with associated fever and leukocytosis.
Fistulae may likewise be manifested by a clear vaginal discharge or may be preceded by fever, leukocytosis or abdominal or flank pain. Unrecognized bladder injuries may be associated with a clear watery vaginal discharge immediately or several days after surgery. To identify the injury, a speculum can be placed in the vagina and, if the fistula is not apparent, dye or milk can be instilled through the urethra to identify the leak. An alternative technique is to place sponges in the vagina and then instill dye into the bladder through the urethra. If only the upper sponge is stained, a vesicovaginal fistula may be present. If only the lower portion is stained, urine loss is probably occurring through the urethra. If neither portion is stained but the upper sponge is wet, a ureterovaginal fistula may be present.
Ureteral injuries can be managed by cystoscopic or percutaneous stenting of the damaged ureter, which is a less aggressive approach than the option of reexploration and surgical repair.
Traditionally, management of vesicovaginal fistulae has included prolonged catheter drainage of the bladder, antibiotic therapy and, if indicated, hormone replacement therapy. The report states that early surgical repair after resolution of infection has recently been emphasized. Most cases of vesicovaginal fistulae should be repaired vaginally, with the abdominal approach reserved for large or complex fistulae or for those that form as a result of irradiation.
Ureterovesicovaginal fistulae are usually repaired abdominally, with closure of the vaginal defect, ureteral reimplantation and use of an omental graft to separate layers and provide a new blood supply. The report states that enterovesicovaginal fistulae may be best repaired in a two-step approach: (1) diverting the gastrointestinal tract and closing the urinary fistula and (2) reestablishing gastrointestinal continuity. As an alternative, the procedure may be performed in one step.
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