Vesico vaginal fistula

for medical students

1. VESICO-VAGINAL FISTULA DR. SEEMA NISHAD MODERATOR- UNIT 1

2. Definition Classification Vesicovaginal fistula Epidemiology Pathophysiology Etiology Etiopathogenesis Classification of VVF Symptoms Examination findings Differential diagnosis Investigation Prevention management

3. FISTULA An abnormal passage or communication that leads from one hollow organ to another. Urogenital fistula- abnormal communication between the urinary ( ureters , bladder, urethra) and the genital (uterus, cervix, vagina) systems. Vesicovaginal fistula is the commonest of all types.

4. Types of fistulas Congenital- (rare) Due to abnormal fusion of ureteric bud and the M ullerian duct with the urogenital sinus or due to abnormal development of the urorectal septum. Acquired- (based on anatomical site of communication)- as vesicovaginal , urethrovaginal , ureterovaginal , ureterouterine etc.

5. Anatomical communications of various U rogenital Fistula URETER BLADDER URETHRA VAGINA URETERO-VAGINAL VESICO-URETERO-VAGINAL VESICO-VAGINAL URETHRO-VAGINAL CERVIX URETERO-CERVICAL VESICO-CERVICAL URETHRO-CERVICAL UTERUS URETERO-UTERINE VESICO-UTERINE NOT REPORTED

6. VESICOVAGINAL FISTULA Communication between bladder and vagina, causing true urinary incontinence. Finding of vesicovaginal fistula (VVF) have been identified in the mummified remains from ancient Egypt in 1923. Most common type of urogenital fistula.

7. Epidemiology In Asia and Africa, up to 100000 new cases of obstetrical genitourinary fistula are added each year to the estimated pool of 2 million women with unrepaired fistulas (WHO- 2014) The incidence is approximately 0.2-1 % in developing countries by retrograde data collection method. India lacks prevalence and incidence data on obstetric fistula.

8. PATHOPHYSIOLOGY TISSUE DAMAGE AND NECROSIS AFTER INJURY CAUSES INFLAMMATION PROCESS OF CELL REGENERATION BEGINS ANGIO-GENESIS STARTS FIRST FIBROBLASTS PROLIFERATE AND SUBSEQUENTLY SYNTHESIZE AND DEPOSIT EXTRACELLULAR MATRIX, PARTICULARLY COLLAGEN (FIBROSIS PHASE) COLLAGEN DEPOSITION PEAKS APPROXIMATELY 7 DAYS AFTER INJURY AND CONTINUES FOR SEVERAL WEEKS SUBSEQUENTLY SCAR FORMATION AND ORGANIZATION (REMODELLING) AUGMENTS WOUND STRENGTH ANY DISRUPTION IN THIS SEQUENCE EVENTUALLY MAY CREATE A FISTULA 1-3 WEEKS AFTER TISSUE INJURY IS MOST VULNERABLE TIME TO ALTERATION IN HEALING ENVIRONMENT AS HYPOXIA, ISCHEMIA, MALNUTRITION, RADIATION OR CHEMOTHERAPY. EDGES OF WOUND EPITHELIALIZE TO FORM CHRONIC FISTULOUS TRACT

9. Etiology of U ro -genital fistula OBSTETRIC CONDITION OR PROCEDURES GYNAECOLOGICAL AND URO-GYNAECOLOGIC PROCEDURES PELVIC/MEDICAL CONDITIONS PROLONGED, OBSTRUCTED LABOR PLACENTA PERCRETA CESAREAN SECTION (ESPECIALLY REPEAT CESAREANS) CESAREAN HYSTERECTOMY OPERATIVE VAGINAL DELIVERY CERVICAL CERCLAGE GISHRI CUT HYSTERECTOMY MYOMECTOMY LOOP EXCISION OF CERVIX VOLUNTARY INTERRUPTION OF PREGNANCY SUBURETHRAL SLINGS ANTERIOR COLPORRAPHY PERIURETHRAL BULKING BURCH COLPOSUSPENSION URETHRAL DIVERTICULUM REPAIR URETERAL WALL STENT ENDOMETRIOSIS GYNAECOLOGIC CANCERS PELVIC IRRADIATION INFECTION (SCHISTOSOMIASIS, TUBERCULOSIS, LYMPHOURANULOMA VENERUM) INTRAUTERINE DEVICE NEGLECTED PESSARY RETENTION OF OTHER VAGINAL FOREIGN OBJECT ACCIDENTAL TRAUMA SEXUAL TRAUMA MITOMYCIN C INSTILLATION BLADDER STONE

10. Etio -pathogenesis In developing countries , most common (70 %) cause is obstetrical due to ischemia or trauma. Ischemia result from- Prolonged compression on the bladder base between fetal head and symphysis pubis in obstructed labor Ischemic necrosis infection sloughing fistula develops in 3-5 days of delivery. Traumatic- caused during instrumental vaginal delivery as forceps application or destructive operation (craniotomy) or may occur during cesarean or cesarean hysterectomy.

11. Gynaecological causes are more common in developed countries. In post-operative cases, rate of fistula formation with procedure type and its indication, as highest chance with radical hysterectomy for cervical cancer and lowest with vaginal hysterectomy for prolapse . Risk factors include cancer stage, intra-operative bladder injury, diabetes and post-operative surgical site infection. Vaginal cancer shows a high likelihood of fistula formation (both vesicovaginal and rectovaginal ) with no association with radiotherapy.

12. Obstetric classification system (Elkin 1999) High risk vesico -vaginal fistula – Size > 4-5 cm in diameter Involvement of urethra, ureter (s) or rectum Juxta -cervical location Inability to visualize the superior edge Reformation following a failed repair

13. Types of VVF based on complexity (Elkins 1999) FISTULA SIMPLE COMPLICATED SIZE ≤ 3 cm > 3 cm LOCATION HIGH VAGINAL MID VAGINAL BLADDER INVOLVEMENT SUPRA-TRIGONAL TRIGONAL AREA PELVIC MALIGNANCY ABSENT PRESENT PRIOR RADIATION THERAPY ABSENT PRESENT VAGINAL LENGTH NORMAL SHORTENED

14. Types based on location TYPE OF FISTULA CHARACTERSTICS HIGH VAGINAL / JUXTA-CERVICAL / VAULT FISTULA PROXIMALLY IN VAGINAL VAULT, COMMUNICATION WITH SUPRATRIGONAL AREA MID-VAGINAL FISTULA PRESENT CENTRALLY IN VAGINA, COMMUNICATION WITH BASE OR TRIGONE AREA OF BLADDER LOW VAGINAL / JUXTA-URETHRAL FISTULA COMMUNICATION BETWEEN THE BLADDER NECK (OR UPPER URETHRA) AND VAGINA LOW VAGINAL / SUB-SYMPHYSEAL FISTULA CIRCUMFERENTIAL LOSS OF TISSUE IN THE REGION OF BLADDER NECK AND URETHRA. THE FISTULA MARGIN IS FIXED TO THE BONE.

15. Surgical classification ( Goh 2004) Integrates- fistula distance from the external urethral meatus fistula size degree of surrounding tissue fibrosis extent of vaginal length reduction Good inter- and intra-observer reproducibility Efficacy in predicting which patients are at risk of post-fistula urinary incontinence and failure of closure.

16. BASIS CHARACTERSTICS DISTANCE OF DISTAL EDGE OF FISTULA FROM THE EXTERNAL URETHRAL MEATUS (IN cm) TYPE 1: > 3.5 cm TYPE 2: 2.5 - 3.5 cm TYPE 3: 1.5 - 2.5 cm TYPE 4: < 1.5 cm FISTULA SIZE IN LARGEST DIAMETER (IN cm) SIZE < 1.5 cm SIZE 1.5 – 3.0 cm SIZE > 3 cm DEGREE OF SURROUNDING TISSUE FIBROSIS AND EXTENT OF VAGINAL LENGTH REDUCTION NONE OR ONLY MILD FIBROSIS (AROUND FISTULA &/OR VAGINA) &/OR VAGINAL LENGTH > 6 cm, NORMAL CAPACITY. MODERATE OR SEVERE FIBROSIS (AROUND FISTULA &/OR VAGINA) &/OR REDUCED VAGINAL LENGTH &/OR CAPACITY SPECIAL CONSIDERATION, e.g. POST-RADIATION, URETERIC INVOLVEMENT, CIRCUMFERENTIAL FISTULA OR PREVIOUS REPAIR

17. Symptoms Classical symptom- unexplained continuous urinary leakage from vagina after a recent operation or difficult vaginal delivery or local trauma. If fistula is small, escape of urine occurs in certain positions and patient can also pass urine normally. Urine leakage occurs from 1 st postoperative day if caused by direct surgical injury. Urinary leakage starts after 7-14 days of obstetric injury. After laparoscopic surgery, it may present after days to weeks.

18. The patient may present with recurrent cystitis or pyelonephritis ; unexplained fever; hematuria ; flank, vaginal or suprapubic pain; and abnormal urinary stream. Irritation of the vagina, vulvar mucosa, and perineum follows, and women report a foul ammoniacal odor. If urine leakage persists, severe perineal dermatitis may result due to exposure of skin to ammonia.

19. As urea is split by vaginal flora, the vaginal pH becomes alkaline, which precipitates greenish-gray phosphate crystals in the vagina and on the vulva. These crystals serve to further irritate what already may be compromised tissue. Large vaginal encrustations are seen with fistulae secondary to neglected vaginal foreign bodies. This constant leakage of urine may make the patient a social recluse; disrupt sexual relations; and lead to depression, low self-esteem, and insomnia.

20. On examination Local examination- a) Extra-urethral urine leakage i.e. Escape of ammonia smelling watery discharge through vagina b) Sodden and excoriated vulvar skin c) Varying degree of perineal tears Vaginal fluid’s creatinine content (> 17 mg/dl) can differentiate urine from vaginal discharge.

21. Per speculum examination- 1) Site, size and number of fistula. 2) If small fistula, only a puckered area is seen on anterior vaginal wall mucosa. 3) Complete perineal tear and recto-vaginal fistula can be present. 4) Metal catheter can be passed through the external urethral meatus into the bladder and if it comes out through the fistula, it confirms VVF and patency of urethra.

22. Associated clinical features like foot drop (due to prolonged compression of the sacral nerve roots by fetal head during labor), complete perineal tear or rectovaginal fistula may be present.

23. Differential diagnosis Uro -genital fistula Stress incontinence Urge incontinence Overflow incontinence Vaginal discharge Erosion of mesh

24. To confirm the diagnosis- Examination under anaesthesia - may be needed for better visualization. Sim’s or knee chest position during examination are helpful. Metal catheter can be passed through the external urethral meatus into the bladder and if it comes out through the fistula, it confirms VVF and patency of urethra. Dye test 3 swab (tampon) test

25. Investigation Cystourethroscopy - confirms the diagnosis. The added information are – exact level, number and location of the fistula and its relation to ureteric orifices and bladder neck. Intravenous urography - for diagnosis of ureterovaginal fistula. Retrograde pyelography -for diagnosis of exact site of ureterovaginal fistula. Voiding cystourethrography - can detect leak in vagina.

26. Diagnosis Age Parity Comorbidities (DM, HTN, post-hysterectomy/post-cesarean) Simple/complex Size Position Type

27. PREVENTION

28. Primary prevention (preventing a cystotomy ) Avoid blunt dissection at the time of mobilization of bladder during hysterectomy or anterior repair, especially when the vesicovaginal space is scarred from the prior cesarean section or other surgery. The precise direction of force cannot be controlled accurately when blunt dissection is used, when compared with sharp dissection. Gentle traction and countertraction are helpful in dissecting the correct plane and thereby preventing direct bladder injury.

29. Direct trauma by retractors, particularly during vaginal hysterectomy may occur. So, retractors should always be used with appropriate caution. Detrimental effect of using monopolar electrocautery may be the cause, so one should consider its use in vesicovaginal space only after carefully considering the risk and benefits.

30. Secondary prevention (early detection and repair) Suspicion of bladder injury per-operatively occurs when- New onset gross hematuria , while the bladder is catheterized. Visualization of fluid in operative field. Routine cystoscopy is not recommended by any guideline but should be done in suspicious cases per-operatively.

31. Cystotomy repair - Evaluate cystoscopically and vaginally to assess the size, location in relation to ureter and trigone and quality of injured tissue. Ureteral catheterization is needed if injury close to ureters . Bladder should be catheterized with trans urethral catheter ( folley’s ) Use of fine surgical techniques, delicate tissue handling and use of suction and irrigation during optimizing visualization.

32. 5. Avoid prolonged clamping of injured tissue during repair and avoid electro- cautery near the injury. 6. Sharply dissect the vesico -vaginal space sufficiently to allow tension free closure. 7. Close the urothelial layer with interrupted or running fine 3-0 delayed absorbable suture. 8. Re- appoximate the muscular layer with running or interrupted 2-0 or 3-0 delayed absorbable suture. Ensure haemostasis . 9. Reinforce repair with third layer of peritoneum using interrupted 3-0 delayed absorbable suture.

33. 10. Ensure integrity of repair and ensure intra- vesical hemostasis . Cystoscopy should be done with minimum bladder filling. 11. Close vaginal injury separately making certain that bladder is not incorporated with vaginal repair. 12. Transurethral or suprapubic bladder drainage to prevent bladder filling to avoid tension on suture line. 13. Determine how long bladder catheterization is needed and ensure orders are written to avoid inadvertent routine catheter removal on the following day.

34. MANAGEMENT

35. Non-surgical management Trans-urethral bladder drainage- particularly used for small fistulas (< 1 cm) that present early (< 3 weeks) and have no evidence of epithelialization of fistula tract. Drainage is done for 4 – 6 weeks. Optimizing nutrition, correcting anemia and improving vaginal estrogenization . Use of collection devices for temporary relief from constant urinary leakage till permanent solution.

36. Conservative surgical management Cystoscopic laser treatment- very limited success and only in small (2-4 mm) supratrigonal fistulas. Fibrin glue- first attempted in 1979 with success. Since then it is used successfully. Autologous platelet-rich plasma- most recent. It was injected trans-vaginally with interposition of platelet rich fibrin to successfully treat 11 out of 12 iatrogenic VVF.

37. Surgical management Indication – when conservative therapy fails or patient is not a candidate for conservative therapy. Principles of surgery- Correct pre-operative assessment and preparation Timely repair Perfect asepsis and good exposure of fistula Excision (minimal) of scar tissue at margins Presence of healthy vascular margin Mobilization of bladder wall from the vagina Tension free repair in 2 layers Fine suture material Minimal use of electrocautery Post-operative bladder drainage

38. Preoperative assessment Fistula status- site, size, number, mobility, extent of fibrosis at margins Urethral involvement Position of ureteric openings in relation to big fistula by cystoscopy Exclude associated rectovaginal fistula or complete perineal tear. Complete hemogram and kidney function tests.

39. Criteria for successful repair (WHO 2006) CRITERIA GOOD PROGNOSIS UNCERTAIN PROGNOSIS NUMBER OF FISTULA SINGLE MULTIPLE SITE VESICOVAGINAL FISTULA RECTOVAGINAL FISTULA (RVF), MIXED (VVF AND RVF ) SIZE < 4 CM >4 CM URETHRAL INVOLVEMENT ABSENT PRESENT VAGINAL SCARRING ABSENT PRESENT TISSUE LOSS MINIMAL EXTENSIVE URETER INVOLVEMENT URETERO-VAGINAL FISTULA PRESENT NO URETERO-VAGINAL FISTULA CIRCUMFERENTIAL DEFECT (URETHRA SEPARATED FROM BLADDER) ABSENT PRESENT

40. Preoperative preparation Improvement of general condition and anemia Ensure good nutrition Treat local infection in vulva and vagina Treatment of urinary infection. May give urinary antiseptics at least 3-5 days prior to surgery. To clean the area with vinegar to dissolve and remove phosphate crystals and then application of zinc oxide ointment for healing of excoriation at vulva.

41. Various routes of fistula repair Abdominal Vaginal Trans-peritoneal Trans- vesical Laparoscopic Indication for Trans-peritoneal and Trans- vesical approaches- Fistula located high up and vagina is narrow Fistula close to ureteric openings Previous failed repair Large or complex fistula When an interposition graft is needed.

42. Vaginal approach Latzko technique- steps are as follows- Stay sutures are placed to help stabilize and bring the fistula distally towards the operating surgeon Vaginal epithelium sharply dissected and excised circumferentially about the fistula completed epithelial excision around the fistula Fistulous tract is imbricated into the bladder cavity with sequential layers of interrupted 3-0 or 4-0 delayed absorbable suture. First extra-mucosal layer closure of vagina Closure of the vaginal epithelium.

43. Saucerisation : Evolution of surgical management of urogenital fistula was made by Morison Sims in 19 th century. Original Marion Sims’ technique used for a very small fistula, particularly for residual fistula after previous surgery. A bevelled cut through the vagina to the small visceral aperture should clear scar tissue to allow healthy tissues for apposition.

44. Abdominal approach Retro-pubic intra- vesical VVF repair- Retroperitoneal anterior bladder incision Fistula is identified and circumscribed and vesico -vaginal space is dissected radially . First layer incorporates the vaginal epithelium in a vertical closure using interrupted sutures. Bladder muscularis is closed with interrupted suture in a horizontal orientation. Urothelium is closed with fine interrupted suture to complete the repair. The anterior bladder incision is closed in layers.

45. Trans-peritoneal trans- vesical VVF repair- The bladder is incised midline from its anterior portion back posteriorly until the fistula is reached, the fistula is excised and ureters are protected. Dissection of vesico -vaginal space distal to the fistula to allow tension free closure in layers. Vagina is closed transversely with the interrupted delayed absorbable suture with the knots located inside the vagina. A second layer of vaginal closure is done to imbricate the first layer.

46. 4. The dependant portion of the bladder is usually closed side to side with the interrupted double-layer closure of the bladder without tension. 5. The rest of the bladder incision is closed with running suture in 2 layers. 6. Prior to complete closure of bladder, a suprapubic catheter is placed through a separate stab incision. 7. Omental flap (partially detached by severing its vasculature on the left along the curvature of stomach) is anchored in vesico -vaginal space. 8. Cystoscopy is done to verify watertight closure and ensure intravesical hemostasis .

47. Martius ( bulbocavernosus ) fat pad transposition- An incision is made over the labial fat pad dissected bluntly and with electrocautery ensuring adequate hemostasis and a continued blood supply from the chosen pedicle ( anteriorly from external pudendal and posteriorly from internal pudendal artery). A submucosal tunnel is created and enlarged to ensure adequate blood flow to the tip of the graft.

48. The graft is carefully pulled through the tunnel to the area needed and sutured in place. Hemostasis of donor site is verified and then skin and vaginal mucosa incisions are closed.

49. Post-operative care Urinary antiseptics Continuous bladder drainage for about 10-14 days. Nursing care for fluid balance, urine output and to detect any catheter block 1 hourly urine output charting Check pH of urine twice daily. Always keep urine acidic to avoid crystalization of phosphate and stone formation. Early ambulation to prevent DVT Pelvic rest for 12 weeks Prevention of constipation

50. Advice on discharge To pass urine more frequently. To avoid intercourse for at least 3 months To defer pregnancy for at least 1 year. If conception occurs, mandatory antenatal checkups and hospital delivery by cesarean section.

51. In case of repair failure Repair should again be attempted after 3 months.