Fistulae of the urinary tract: Vesicovaginal, ureterovaginal, and rectourethral
A fistula is an epithelialized or endothelialized connection between two or more organs. Frequently, it will be named after the organs or systems affected. Some fistulae can be made intentionally to treat a condition, others develop as a consequence of a noxious event, most of the time in the treatment of a condition.
Urogenital fistulae are among the most common throughout the literature. Different levels of pressure between the urinary, digestive, and genital system make this type of fistula easy to develop. The World Health Organization estimates 130,000 new cases per year worldwide.
Having a fistula represents a distressing condition that will reduce a person’s quality of life. All the efforts to improve this condition must be made, and a successful index repair is the desired goal.
Minimally invasive approaches have led us to improve historically morbid surgical procedures. Early experience with laparoscopic surgery improved the outcomes. However, highly complex surgical maneuvers had to be performed, and the learning curve was difficult to reach. Robotic-assisted laparoscopic surgery improved upon many of the advances already made, and this technology gives us the best chances for a successful index/primary repair. Several characteristics such as improved intracorporeal suturing, a magnified view, tremor reduction, and a high degree of mobility make this possible.
In this chapter, we will be reviewing the most important aspects of the vesicovaginal, ureterovaginal, and rectourethral fistula and discuss the robotic repair of each condition.
Vesicovaginal fistula
Vesicovaginal fistula (VVF) is an abnormal communication between the bladder and the vaginal epithelium. It is considered a devastating condition characterized by involuntary and continuous urine leakage per vagina, and recurrent urinary tract infections, resulting in significant psychosocial distress, isolation, and hygiene problems. ,
Incidence
The exact incidence of VVF is not known, but it is believed to affect up to 2% of women worldwide. The cases are geographically distributed disproportionally, depending on the country’s development.
In developing countries, the incidence is around 1%. Of these, 98% occur due to obstetric causes, where obstructed or prolonged labor leads to vaginal ischemia and subsequent fistula formation. Iatrogenic bladder injury during cesarean section (C-section) also has a higher incidence compared to developed countries (2.4% vs. <1%, respectively). In addition, inadequate access to obstetric healthcare, poor nutrition, and early age at first childbirth are frequent clinical scenarios that may predispose to fistula formation.
In contrast to developed countries, where the incidence is around 0.3%, the most common etiologies are iatrogenic injuries during pelvic surgery, such as hysterectomy, occurring in 1 of every 1800 procedures, sequelae of malignant diseases, pelvic radiation, infections, foreign bodies, and trauma. Obstetric procedures as a cause of VVF encompass only about 20%, with twin delivery and labor dystocia being the most common causes. ,
Classification
VVF can be classified by complexity. Complex fistulae include:
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Size equal to or greater than 2.5 cm
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Failed repair attempts
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Postradiotherapy
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Localized in the trigone or near the ureteral orifices (UO)
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Multiple tracts
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Associated with ureteric strictures, ureterovaginal or rectovaginal fistula
Simple fistulae are those that do not comply with the above.
Diagnosis
Digital vaginal examination and the use of speculum can provide invaluable information about vaginal anatomy and tissue characteristics, while enabling fistula identification. Methylene blue instillation into the bladder in a retrograde fashion and tampon placement in the vaginal vault may confirm the diagnosis by staining the tampon after ambulation.
Cystoscopy is the gold standard for diagnosis, providing information about size, location, tissue quality, fistula proximity to the UO, and if there are any other fistulae associated. Upper urinary tract evaluation should be mandatory, since 12% of the cases may have a concomitant ureteral injury, which can be evaluated with computed tomography (CT) urogram or magnetic resonance imaging (MRI).
Conservative treatment
Conservative treatment should be used as the first intervention in any patient presenting with VVF unless the fistula has clear indications for surgical repair. This includes continuous bladder drainage for up to 12 weeks, allowing tissue healing. If no beneficial change has occurred within this timeframe, resolution by conservative methods is unlikely to occur due to epithelization of the fistulous tract.
Spontaneous closure happens in only 7% to 12.5% of the cases, and it has been described only in patients with a simple fistula.
If conservative management is unsuccessful, transvaginal or transabdominal surgical repair can be done, with reported success rates of 93% and 91%, respectively.
Timing of surgical repair
As the best chance of success is with the first repair, appropriate timing of surgical repair is essential. In cases where the fistula presents immediately after a surgical procedure, a prompt surgical repair is recommended, as delaying it may result in loss of tissue planes and fibrosis. However, in cases of VVFs caused by other etiologies, it is preferable to perform the surgical repair at least 3 to 6 months after the initial diagnosis to allow the tissue inflammation to settle. Routine follow-up with cystoscopy and vaginoscopy to exclude inflammation, cystitis, or encrustation is critical.
Surgical treatment
Currently, there is no consensus about the best surgical approach. The fundamental principles of fistula repair must be followed to ensure a successful outcome; these include adequate exposure of the fistulous tract, excision of nonviable tissue from fistula edges, use of well-vascularized healthy tissue for repairs, watertight and tension-free closure, nonoverlapping suture lines, flap interposition, and adequate bladder drainage following the repair. ,
Transvaginal approach
The initial repair is usually attempted transvaginally, due to the anatomic familiarity to gynecological surgeons who are often the first to encounter this clinical scenario. , Proponents of this repair noted advantages in terms of a better approach for low-lying fistulae, lower patient morbidity, blood loss, and postoperative bladder irritability. Moreover, the procedure may be done in an outpatient setting, postoperative pain is minimal, and success rates are nearly equal to those achieved by the abdominal approach. However, vaginal exposure has its limitations, especially when the VVF is high-lying and the vagina is severely scarred.
Transabdominal approach
The transabdominal approach has enjoyed reproducible and durable success. Indications include fistulae greater than 2.5 cm, high-lying or retracted fistula in a narrow vagina, close proximity to the UO, concomitant ureterovaginal or rectovaginal fistula, multiple tracts, after radiotherapy, morbid obesity, or associated intra-abdominal pathology that requires simultaneous care as this will permit better exposure of the tissue for repair. ,
Minimally invasive approaches
With the ongoing improvement in minimally invasive techniques, surgeons are increasingly performing reconstructive procedures laparoscopically or robotically. The first laparoscopic VVF repair was described in 1994. Laparoscopy enables an improved but limited cystotomy compared with the historically morbid O’Connor procedure, in which the bladder is bivalved at the level of the fistula. A laparoscopic approach has the advantages of a minimally invasive procedure, including magnification during the procedure, hemostasis, decreased abdominal pain, and a shorter hospital stay with more rapid recovery when compared with open surgery. Nevertheless, the laparoscopic approach was not widely accepted due to difficult pelvic access, a bidimensional visual field, fulcrum effect, and long instruments with limited degrees of freedom.
Therefore, a decade later, in 2005, the first robotic-assisted laparoscopic repair was reported, which quickly superseded laparoscopic approaches, providing three-dimensional anatomic visibility, more precise dissection, and enhanced tissue manipulation with wristed instrument dexterity.
Different robotic surgical approaches are standardized among the literature, based on the plane used to identify the fistulous tract for its repair.
To date, the surgical approach is defined by the surgeon’s preference.
Retrovesical.
The retrovesical approach involves accessing the fistulous tract in an extravesical manner. This was proposed as a safer option as it causes less trauma to the bladder. However, the dissection planes can be complicated to delineate and lead to inadvertent ureteric or cervical canal injuries. This difficulty is even more challenging when cases are associated with prior radiotherapy, malignancies, uterus presence, and if the VVF is a consequence of an injury during a C-section. Therefore, we recommend a transvesical approach when uterus preservation procedures are performed. ,
Transperitoneal-transvaginal.
This approach involves opening the vagina toward the fistula defect. It might be attempted in patients where the dissection of the vesicovaginal space is challenging to perform. This approach attempts to prevail over the difficulties of retrovesical and transvesical approaches. However, only small series have been reported to date, and this approach is still in development.
Transvesical.
The transvesical approach is considered an adaptation of the O’Connor procedure, where an intentional vertical cystotomy toward the fistula allows direct visualization of the UO and wide dissection of the fistulous tract. Complications such as decreased bladder capacity, recurrent urinary tract infections, and detrusor dysfunction have been reported as a consequence of the cystotomy.
Herein, we will describe the step-by-step surgical technique of the robotic-assisted laparoscopic repair of VVF using transvesical approach.
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Cystourethroscope 22 Fr with a ureteric catheterization bridge (30 degree telescope)
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Da Vinci Xi Robotic Surgical System (Intuitive Surgical, Sunnyvale, CA)
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Three trocars (8 mm)
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0 and 30 degree 3-D laparoscope
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Hot shears (monopolar curved scissors)
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Maryland bipolar forceps
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Two large needle drivers
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Two ProGrasp forceps
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One trocar (12 mm) for the robotic telescope
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Two trocars (5 mm) for the bedside assistant
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5-mm endoscopic long suction irrigator (45 cm)
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5-mm endoscopic scissors
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5-mm endoscopic locking grasper
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5-mm endoscopic needle driver
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Monopolar/bipolar electrocautery
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5.5-mm Ethicon UltraCision harmonic scalpel coagulating shears, pistol grip (36 cm, 15-mm active blade—5.5 mm diameter)
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3-0 V-Loc absorbable wound closure device (barbed suture) on a UR-6 needle (Covidien, Dublin, Ireland)
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Two long mono-J ureteric stents 7 or 6 Fr with guided wire (Bander Ureteral Diversion Stent Set, Cook Urological, Inc., Spencer, IN)
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Methylene blue
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Jackson-Pratt drain
Step-by-step transvesical robotic surgical technique
The patient should undergo mechanical bowel preparation the day before surgery. Prophylactic antibiotics are started and continued in the perioperative period (amoxicillin/clavulanic acid or cefazolin or ceftriaxone + metronidazole). The patient is positioned in lithotomy, and a cystoscopy is performed to catheterize both ureters using double-J stents. The fistula orifice is cannulated using a different colored ureteral catheter, which will be retrieved through the vaginal canal. The maneuver will offer better intraoperative identification and protection during fistula dissection.
Port placement occurs following the open laparoscopic access for the first trocar. Pneumoperitoneum is established using high-flow carbon dioxide insufflation up to 15 mm Hg, and subsequent trocars are placed under direct visualization in a six-port transperitoneal configuration ( Fig. 32.1 ).
First, an omental flap is harvested, replicating the open omentoplasty technique. For this section of the procedure, the patient is positioned in reverse Trendelenburg with the da Vinci Xi Robotic Surgical System (Intuitive Surgical) in cephalic view.
Next, the patient is positioned in steep Trendelenburg position, which will ease adhesiolysis and keep the pouch of Douglas free of bowel loops. Adhesiolysis is performed using sharp and blunt dissection until the superior bladder and the surface of the uterus (if present) are anatomically identified.
A longitudinal cystotomy is performed with the monopolar robotic scissors just above the fistulous tract that can be identified either by pulling the previously placed catheter or by switching off the robotic camera light and focusing the cystoscope light on the fistula ( Figs. 32.2 and 32.3 ). At this moment, the vagina must be packed with a wet sponge to be able to maintain pneumoperitoneum.
The cystotomy is advanced until the borders of the fistulous tract, followed by excision, leaving a healthy margin of approximately 2 mm, and the communication between the two organs becomes more evident ( Fig. 32.4 ). The anatomical plane between the bladder and the vagina has to be separated for later interposition tissue anchoring ( Fig. 32.5 ). The vagina is closed in a transverse running locking fashion using a 3-0 V-Loc suture (Covidien) on a UR-6 needle ( Fig. 32.6 ).
