Vesicovaginal Fistula- Review with reference to Indian scenario
Vesicovaginal fistula has been one of the most unfortunate accompaniments of the virtue of procreation bestowed upon womanhood. It has been known to have occurred in royal family of Egypt as long ago as 2050 BC, having been preserved as a mummy (1). Not very long ago, Princess Charlotte, daughter of George IV of England succumbed to the consequences of obstructed labour in the year 1817 (2). Vesicovaginal fistulae could be classified on the basis of etiology as either arising out of an obstetric cause or resulting from a gynecological procedure. With the development of medical science there has been a shift in the etiology of VVF from obstetric to gynecological causes. However the situation has not changed much in developing nations where sub optimal ante natal care continues to add to the various other miseries faced by women. According to WHO report on Global Burden of disease study, obstructed labour affects at least 7 million women every year out of which 6.5 million belong to underdeveloped countries. If only 2% of these obstructed labours result in formation of VVF, then every year 130,000 women are being affected by this dreadful complication (3). It is worth noting that while in a study published from UK, out of 166 cases of VVF treated over a period of 18 years, only 21(12.6%) were caused by obstetric reasons while a similar study from Nigeria reported 369 (97.8%) out of a total of 377 cases of VVF to be related to child birth (4).
The scenario appears to be changing in India and an increasing proportion of fistulae secondary to pelvic surgeries are being reported. This is perhaps the result of slowly improving medical facilities in the country, which are yet far from optimum. There are no widespread true cross sectional studies from India to determine the incidence of VVF. According to the UNFPA report presented at the South Asia conference for the prevention and treatment of obstetric fistula held at Dhaka, Bangladesh in 2003,a summary of various surveys reported an incidence of VVF being 0.3 – 0.5% among selected pockets of population in India (5). This has to be viewed in light of the fact that India is vast country with diverse socio economic strata consisting of entirely different conditions of literacy, healthcare, per capita income etc. The rural conditions are totally different from the urban scenario making any generalizations meaningless. This could be well appreciated from the fact that various published studies from India have reported the percentage of obstetric fistulae as 93%, 83%, 75.79%, and 71.87%of the total vesicovaginal fistulae seen. (6,7,8,9). All (100%) of the15 patients in two recently published small series consisting of 8 and 5 patients treated by laparoscopic surgery and robotic surgery respectively had contracted VVF secondary to Gynecological surgery (10).
Classification of VVF
Vesicovaginal fistulae can be classified according to the site, size and involvement of the sphincteric mechanism. Obstetric fistulae are mainly are Vesicovaginal (90%), Rectovaginal (5%) or combined VVF and RVF (5%)(11). The multiplicity of available classification systems is a testimony to the fact that none really addresses the issues of reproducibility, choice of procedure and prognosis. Broadly a VVF may be classified as simple or complex as indicated in the table1 (12).
Prognosis of a VVF depends upon the size of the fistula, scarring in the operative area, involvement of the continence mechanism, associated injuries like RVF. The prognosis worsens if there have been any previous attempts at the repair.
Approach to a patient with VVF
A patient with urinary fistula is in a miserable state as more often than not she has been socially isolated and physically frustrated trying to save the most tender portion of her skin from ammonia dermatitis in addition to containing wetness. A multi dimensional holistic humane approach will go a along way in healing these individuals. Taking a good history in these patients must include any pre existing urinary symptoms prior to development of fistula like stress incontinence or urge incontinence. A note must be made of any known medical co morbidities. On examination, an effort should be made to assess the fistula with a view to plan the surgical procedure including the possibility of ureteric reimplantation. Some times especially in a post-surgical urinary fistula, there may be difficulty in differentiating between an Ureterovaginal or a Vesicovaginal fistula. In such situations, a “ three-swab test” may be done to differentiate these entities from each other and also from severe stress incontinence and true sphincteric incompetence. In a rare case of confusion between Ureterovaginal and Vesicovaginal fistula, a “double dye test” may be carried out.
Three swab test
This is a simple test to differentiate between various forms of incontinence in women who are unable to give a definite description of their problem. It involves examination of the patient in lithotomy position, introduction of three swabs in the vagina and filling the bladder with a blue dye, which is usually, sterilized methylene blue or indigo carmine, by means of a soft catheter. The outermost swab is then discarded as it could have been soiled while filling the bladder. The patient is then asked to strain or perform Valsalva maneuver. If the outer of the two residual swabs is wet with blue dye, it indicates sphincteric incompetence or stress urinary incontinence. If the inner swab is wet and blue but the outer swab is dry it indicates Vesicovaginal fistula. If the inner swab is wet but not blue then it is Ureterovaginal fistula.
Double dye test
If there is confusion in the diagnosis between Vesicovaginal and Ureterovaginal
fistula, the patient is advised to report after 2 hours of taking 2 oral tablets
of Pyridium (Phenazopyridine). A tampon is placed in vagina and bladder is filled
with a blue dye, which is usually, sterilized methylene blue or indigo carmine,
by means of a soft catheter. The tampon is removed and examined after a few minutes.
While the blue colour indicates a Vesicovaginal fistula, orange- red colour signifies
Planning the treatment
Vesicovaginal fistula in a woman may be encountered in three situations.
The various surgical interventions that could be carried out in VVF have been listed in table2. Small fistulae may be induced to heal if the margins are cauterized using electric diathermy. This is expected to debride the less vascular scar tissue and allow healthy granulation tissue to fill a tiny gap while the bladder is kept collapsed by a soft catheter not rubbing against the injured area.
Dogra et al have reported successful ‘Laser welding’ of a tiny fistula from India in the year 2001.They used Nd Yag laser to coagulate a small epithelialised communication between bladder and vagina following abdominal hysterectomy (18).
The question of the right surgical approach to VVF is primarily a matter of training
of the treating surgeon and the fistula characteristics. Both vaginal and abdominal
approaches have their merits and demerits. While vaginal repair could be carried
out under regional anesthesia with minimal disturbance to the bowel function allowing
early oral diet, abdominal approach has to it’s advantage the fact that wide mobilization
of bladder wall could be carried out to patch up large defects without tension on
the tissues. While operating trans abdominally one can easily reimplant a ureter
with doubtful integrity of ureterovesical junction. Also, omentum could be mobilized
and interposed between vagina and bladder. Advent and refinements of laparoscopic
techniques have already shown promising results in the treatment of VVF. (19,20)
Recently Hemal et al from India have reported a series of 5 patients with post surgical
VVF treated successfully using robotic surgery (21).
Complications of surgical repair
1) Immediate postoperative complications require urgent attention. These may present as following:
2) Long term complications when occur may include:
Challenges in the treatment of VVF
The single most dreaded complication of VVF repair is the failure to close the fistula.
Therefore before attempting to repair a VVF, the surgeon should do every thing to
make the treatment a success. Despite best of efforts in about 10% cases when the
catheter is removed and the woman is incontinent. At this stage it is wise to look
for causes of incontinence and differentiate them from leakage of urine due to loss
of anatomical integrity of the lower urinary tract. A ‘dye test’ is of benefit in
these situations and may reward the surgeon by proving the integrity of bladder.
Long standing large fistulae can cause reduced capacity of the urinary bladder thus
leading to severe urge incontinence. Loss of the continence mechanism either due
to the initial insult or surgical procedure itself may be responsible for true or
stress incontinence. Mixed incontinence may be encountered when both of these coexist.
Treatment of these conditions is physiotherapy and pharmacotherapy with antimuscarinic
agents (Tolterodine, Solifenacin) and sympathomimetics (Dulexetine).