In the industrialized world, the most common causes of genitourinary fistulas are surgery, malignancy, and radiation therapy, alone or in combination. Most often a vesicovaginal fistula develops after an otherwise uncomplicated vaginal or abdominal hysterectomy in which a small portion of the bladder was inadvertently trapped in a surgical clamp or was transfixed by a suture. These fistulas most often occur at the vaginal apex and are no larger than 1 to 2 mm. The amount of urine that can leak through a fistula of any size, however, is enormous. Figure 26.3 shows a cystoscopic view of three small vesicovaginal fistulae, lined up where the cuff suture line would have been. With traditional vaginal and abdominal hysterectomy, many surgeons recommend universal cystoscopy at the completion of the surgical case to assess for urinary tract injury and potentially decrease the incidence of urinary tract fistula. A review of 839 patients undergoing hysterectomy for benign disease followed by universal cystoscopy at completion of the procedure revealed lower urinary tract injury in 4.3%, including bladder injury in 2.9% and ureteral injury in 1.8% (21).
With the increase in minimally invasive techniques for pelvic surgery, including hysterectomy, the use of electrocautery devices is commonplace. This more frequent use of electrocautery for ligation of vessels and the resulting thermal spread increases concern about the possibility of ureteral damage that may lead to ureterovaginal fistula. When significant urine leakage occurs, often 10 to 14 days following a laparoscopic hysterectomy, ureterovaginal fistula should be strongly considered in the differential diagnosis. As with abdominal and vaginal surgery, careful attention to the location of the ureter, especially in proximity to the uterine arteries, must be a standard precaution. The incidence of ureterovaginal fistula after laparoscopic hysterectomy appears to be 1% to 4% (22).
Although rare, vesicouterine fistulas are increasing in incidence as the rate of cesarean deliveries increases. Such fistulas are almost always associated with repeat cesarean deliveries. The classic triad of vaginal urinary leakage, cyclic hematuria, and amenorrhea is known as Youssef’s syndrome (23).
Nocturia Nocturia is the number of voids recorded during a night’s sleep; each void is preceded and followed by sleep. To sort out whether nocturia results from heightened urine production at night, the nocturnal urinary volume can be assessed from a bladder chart. Nocturnal urinary volume is defined as the total volume of urine passed between the time the woman goes to bed with the intention of sleeping and the time of waking with the intention of rising. Thus, it excludes the last void before going to bed but includes the first void after rising in the morning. Nocturia can be the result of nocturnal polyuria potentially related to delayed mobilization of ﬂuid especially in the elderly, sleep problems (e.g., sleep apnea), or low volume voids. Nocturnal polyuria is present when an increased proportion of the 24-hour output occurs at night.