Fistula: A Hole In The Bladder
A fistula is an abnormal passage or connection between a hollow body cavity, like the bladder, and the surface of the body. A vesico-vaginal fistula is a fistula connecting the bladder with the vagina: a urethro-vaginal fistula connects the urethra to the vagina. Vesico-vaginal and urethro-vaginal fistula result in severe urinary incontinence because there is uncontrollable leakage of urine through the fistula, which bypasses the urethra and the sphincter and comes out the vagina. If the bladder was like a balloon and the knot that keeps the air from leaking out was like the sphincter, a fistula is like a hole in the balloon. In the United States and other industrialized countries, fistulas are almost always the result of complications from pelvic surgery (hysterectomy, prolapse repair and anti-incontinence surgery). Rarely, they may be caused by cancer of the cervix or uterus, particularly those treated with radiation. In underdeveloped countries, they usually result from childbirth (obstetric) injuries.
Amongst expert fistula surgeons, the success rate is very high after a single operation for vesico-vaginal fistula, probably well over 90% and nearly 100% if a first operation fails and a second is done. Surgical treatment of these terrible injuries has become a special interest of mine. I learned that by repairing the incontinence at the same time that the fistula is surgically repaired, it was possible to cure both the fistula and the incontinence in over 90 % of women, provided that a tissue graft bringing in a new blood supply (a Martius graft) was done in conjunction with a pubovaginal sling. I'll discuss what these words mean after describing how the surgeries are done. In the industrialized countries of the world, like the USA, Canada and Western Europe, fistulas usually are the result of surgical complications from relatively simple operations such as anti-incontinence procedures, hysterectomy, prolapse surgery or urethral diverticulectomy. In addition, if not properly cared for, the injudicious use of indwelling urethral catheters may result in pressure necrosis, in other words tissue death of the urethra. This is most commonly seen in quadriplegic or paraplegic women, but is occasionally encountered in otherwise normal women who have had a prolonged recovery after a devastating illness or injury. This form of injury is particularly disconcerting since it is entirely preventable by routine hygiene, observation and changing the catheter frequently. Rarely, urethro-vaginal or vesico-vaginal fistula may result from an injury to the urethra and/or vesical neck sustained after trauma to the pelvis, particularly when there has been a fracture of the pubic bone. Rarely there may be local invasion of these tissues from cancer of the pelvis or damage from radiation treatment which results in a fistula.
Regardless of the cause of the fistula, the consequences to the patient are devastating and the diagnostic and therapeutic challenges to the surgeon are considerable. Effective treatment begins with an accurate diagnosis and diagnosis begins with a high index of suspicion on the part of the physician. Sadly, many, if not most fistulas are initially misdiagnosed because the symptoms are attributed to some other cause. A high index of suspicion means that the doctor should suspect fistula whenever a woman complains of urinary incontinence shortly after childbirth, vaginal surgery of any type or hysterectomy or after surgical or radiation treatment of cervical or uterine cancer. Further, he or she should be suspicious of fistula in any woman who complains of incontinence, but on examination, urine is not seen to leak from the urethra.
The most common symptom of a urinary fistula is a constant or nearly constant leakage of urine, both day and night. Some women with small fistulas urinate fairly normally even though there is a continuous leakage; others leak so much that there is never enough in the bladder for them to urinate at all. In many fistula patients, the leakage is so bad that they constantly soak through incontinence pads which are changed frequently throughout the day.
In the vast majority of patients the diagnosis will be obvious to your doctor if he does a physical examination when you have a full bladder. If you develop incontinence after childbirth or one of the operations listed above, you should be examined by your doctor, preferably with a full bladder. He should examine the vagina looking for the source of the urinary leakage. If the leakage is not seen, the doctor should pass a catheter and fill the bladder and look again. If the source is still not apparent, he or she might want to put some dye in through the catheter to help him or her visualize the leakage. Rarely, it will be necessary to do an X-ray or CAT scan to make the correct diagnosis. Once the diagnosis is confirmed, it is important to make sure that there are no other injuries to the bladder, urethra or ureters. Once an accurate diagnosis has been made and other injuries excluded, it is time to consider your treatment options.
For practical purposes, the only treatments for fistulas are surgical. Some doctors recommend that an indwelling catheter be left in place for a prolonged period of time (weeks or months), to give the fistula a chance to heal on its own. Although there have been a few reports of success using this method, most of the time it is unsuccessful and only delays the otherwise inevitable surgery. Further, it is very frustrating for a woman to spend weeks or months with a catheter in place, especially because the catheter usually is ineffective in controlling the leakage and, aside from the liberal use of absorbent pads, there is no good way of keeping her dry.
There are two main types of surgical repair for a vesico-vaginal fistula - an abdominal repair and a vaginal repair. In general, although there are distinct advantages and disadvantages to each method, the decision to use one or the other is based mostly on the experience and skills of the surgeon. This type of surgery requires a great deal of experience on the part of the surgeon, and, for this reason, it is particularly important to choose a surgeon who has such experience. It really doesn't matter whether he is a urologist or gynecologist so long as he or she has done plenty of these operations and has a good success rate. In the hands of a skilled surgeon, the chances of success ought to be well over 90% or more unless the fistula has been caused by radiation or cancer. In those cases, the success rate is lower, being about 60-80%.
How do I actually choose a surgeon? Is it OK to use the doctor who did the operation that caused the problem in the first place?
Finding an experienced surgeon to repair the fistula is not an easy task because fistulas are not very common in industrialized countries and, therefore, there are not many experienced surgeons. I think there are probably experienced surgeons in most large cities and towns, but you really have to check for yourself. If you chose your surgeon carefully in the first place, the chances are that he is highly skilled. If he or she diagnosed your fistula in a timely fashion (within a few days or a week or two) and exhibited care and concern, the best place to start is to discuss the problem with him or her. It may well be that he or she is experienced at performing fistula surgery. If your surgeon is not so experienced, he or she will probably be able to refer you to an experienced surgeon. In general, the more fistula operations a surgeon has performed, the better he or she is, but that's a fallible rule. A young doctor who spent a month in Africa doing 100 fistula operations is not as experienced as an older doctor who did 10 a year for ten years and got to see his results. You should question the doctor directly. Ask about how many fistula operations he or she has done, did he get good follow-up and what is his success rate. There's no way to grade the success of the surgeon and there's no easy way to be sure that you've chosen the right one, but there are common sense guidelines. Because fistulas are so rare, you're unlikely to find a doctor who's operated on more than a dozen or so. A real expert in industrialized countries may have done a hundred; in Africa a real expert might do thousands of fistula operations, but rarely gets the chance to follow-up on his personal success rate. If your doctor has done a dozen and all were successful, that's pretty good; if all failed I'd stay away from that doctor. If his success is over about 80% that's OK, but I'd rather have a surgeon whose success is well over 90%. If he or she says that the success rate is 50% or less, I'd look for another surgeon. The surgeon really should have a pretty idea of what his or her own success rate is because, not only are fistulas rare, but when the surgery is unsuccessful, it's almost always apparent within the first 2 - 4 weeks.
There are distinct differences between a vaginal and abdominal approach to fistula repair. All things being equal, the vaginal approach is far more preferable for a number of reasons. Firstly, the surgery is done completely through the vagina so there is no visible scar. Secondly, without an abdominal incision, the post-operative recovery is much easier and less painful and there is much smaller chance of wound infection and other complications. Further, there is less blood loss and a smaller chance that you will require a blood transfusion.
OK, I'll take the vaginal approach.
It's not quite that simple. In the hands of all but the most expert of fistula surgeons, the abdominal approach probably has a considerably higher success rate. Furthermore, the vaginal approach can result in more vaginal scarring; it can shorten the vagina and cause painful intercourse (dyspaerunia). And in some women, the vagina is simply too small or the fistula is up too high for the surgeon to be able to adequately expose it. In these instances, an abdominal approach should be used. In addition, if there has been an injury to the ureter or the intestine, an abdominal approach is needed so that both surgeries can be accomplished at the same time. Further, many urologists are not familiar with the vaginal approach and many gynecologists are not familiar with the abdominal approach. In some instances, at the discretion of your surgeon, it may be better to perform the surgery with a combined approach, through both the vagina and abdomen in order to insure a successful outcome.
No matter which approach is chosen, it is often advisable to bring in a new blood supply to the damaged area to insure that enough oxygen reaches the tissues to allow proper healing. The two most common ways of doing this are with a Martius labial fat pad graft and an omental flap.
Timing of surgery and preoperative management
In the past, much controversy surrounded the timing of surgical repair. For decades it has been taught that surgery should be delayed for 3 - 6 months or longer to allow adequate time for the tissue to heal and for inflammation and selling (edema) to subside. Most experts now agree that surgery can be safely performed as soon as the vaginal wound is free of infection and inflammation and the tissues are reasonably pliable (soft). It is almost always possible to perform the surgery within a few weeks after the original surgery.
Management of incontinence while waiting for healing of the vaginal tissue is sometimes a difficult problem. In women with small fistulas, bladder catheter drainage is usually sufficient. If significant leakage occurs with a foley catheter in place, it is usually best to remove the catheter and manage the incontinence with absorbent pads until the fistula can be surgically repaired.
Most fistula surgeons, including me, recommend that a catheter be left in place for a few weeks after surgery until the fistula has had a chance to heal, but a few surgeons only leave a catheter in overnight. It's advisable for the surgeon to check that the fistula has healed before the catheter is removed. This is done by examining the vagina at the site of the fistula repair to be sure that it appears healthy and also by filling the bladder with saline or water or dye and checking that it doesn't leak through the vagina. If healing appears incomplete or if there is still leakage, the catheter should be left in another few weeks and then checked again. For practical purposes, the wounds should be well enough healed by a maximum of four weeks. If there is still leakage at that time, the operation has failed.
There are several other approaches that I chose to leave to the end because I don't really approve of them, but I've never tried them either, although I can't say with certainty that it's unwise to try them. The reason I don't try them is because my success rate is nearly 100% with the techniques I already use. These techniques include fulguration of the fistula and the use of surgical glues.
Surgical glue is exactly what it sounds like -- a kind of super glue that can be applied to the fistula to close the hole, much the same way that foam insulation can be injected to fill the cracks in the walls of a building. This technique is quite new and the results are too premature to properly evaluate. One word of caution, though. I have operated on a woman who underwent the surgical glue procedure and failed and it proved to be one of the most difficult cases I've done because the glue had made a large part of the bladder so stiff that it had to be removed in order to repair the fistula. Fortunately, this patient recovered well, but if her bladder had been smaller to start with she might have ended up requiring an even bigger operation to allow the bladder to hold more urine.
For women with urethrovaginal fistulas the situation is even more complicated because in addition to repairing the fistula, it is usually necessary to do an anti-incontinence operation at the same time. One word of caution, though. Not all urethrovaginal fistulas cause a problem and not all have to be surgically repaired. If a urethrovaginal fistula is discovered on examination by your doctor, but you experience no symptoms and have no incontinence, there is no need to repair it at all. However, if there is incontinence, it usually means that the fistula involves not only the urethra, but the sphincter and bladder neck as well.
Surgeries to repair these kinds of injuries are much more complicated than the repair of a vesicovaginal fistula and require a very experienced surgeon. First, the surgeon has to repair the urethra. Then, he has to repair the incontinence. Because he or she is doing so much surgery in such a small place, it is usually advisable to bring in a new blood supply to insure the best chance for healing. This may be accomplished by a Martius labial fat pad graft. Despite the complexity of this surgery, in experienced hands, the overall success rate is over 90% with respect to continence and a successful fistula repair.
Historically, there are three different approaches to repairing these injuries 1) anterior bladder flaps (Tanagho procedure), 2) posterior bladder flaps (Young-Dees-Leadbetter procedure) and 3) vaginal wall flaps. Although these techniques appear to be comparable with respect to repair of the fistula, incontinence persists in about half of the women unless it is repaired at the same time. In my judgment, there is almost never a need to do anything other than a vaginal repair combined with pubovaginal sling and Martius flap. I believe that vaginal reconstruction is considerably easier and faster, much more amenable to concomitant anti-incontinence surgery and has a much easier recovery with fewer complications and blood loss.
Whenever a fistula is diagnosed, one must have a high index of suspicion that there might be other injuries as well which require surgical repair at the same time as the fistula repair. To overlook these would be a travesty, because another surgery would be necessary. There could be a fistula from the ureter to the vagina (a ureterovaginal fistula) an obstruction to the ureter by a suture from the original surgery or there could be sphincteric incontinence. A careful evaluation to exclude each of these potential conditions should be undertaken prior to surgery so that they may be diagnosed beforehand and repaired at surgery. In order to diagnose these conditions, kidney X-rays (IVP and retrograde pyelography) should be performed in all patients whenever possible. Cystoscopy and pelvic examination are also essential.
Further, women with these injuries have usually undergone one or more prior vaginal operations and have urinary incontinence that is very difficult to manage. The vaginal tissues are often very scarred and the blood supply may be deficient. Prior to surgery, careful examination of the vagina is necessary to determine the actual extent of tissue loss and to assess the availability of local tissue for use in the reconstruction. In most instances there is sufficient tissue in the vagina itself to use for the repair, but if the vaginal tissue is extensively scarred and there is not enough tissue for the repair, other areas such as the labia, the abdomen and the inner thigh should be evaluated for possible use for tissue grafts.
Vesico-vaginal and urethro-vaginal fistulas (holes in the vagina connected to the bladder and urethra) are rare in industrialized countries, but are common in the third world because of inadequate obstetric care. The only treatment is surgical and in the hands of experienced surgeons the success rate is very high. Should the surgery fail, a second operation or even a third will almost always be successful in expert hands. Whenever a fistula is diagnosed, a careful search for associated injuries to the ureter should be undertaken and, if found, these injuries should be repaired at the same time.
Women with urethrovaginal fistulas have an even more complicated problem because, in addition to the fistula, there is usually an injury to the sphincter as well. In the hands of experts, after a single operation to repair both the fistula and the incontinence, a successful outcome can be achieved in over 90% of women.