Vesicovaginal fistulae (VVFs)

Fistulae between the bladder and the vagina are the most exacting gynaecological problem in the developing world. Some hospitals in Northern Nigeria have waiting lists of more than 600 patients, most of whom will never be treated. They were once equally common in Europe.

In the developing world VVFs are usually the result of obstructed labour in a young primigravida (18.3), and less often of a traumatic vaginal delivery (particularly with Kielland's forceps), of unskilled Caesarean section, or of rupture of the uterus into the bladder, especially through the scar of a previous section. They can occur: (1) Near the cervix (juxta- cervical). (2) In the middle of the vagina. (3) Near the urethra (juxta-urethral). (4) As a massive combination of the first three. (5) In the vault of the vagina as the result of vaginal surgery. Wherever the patient's fistula, she usually thinks she is incurable, and, as it does not kill her, she is likely to endure great misery for a long time, especially if she is very young (16 is the average age in Northerern Nigeria). She may have lain at home for weeks in a pitiable emaciated state with contractures and bed-sores from lying curled up on her side, expecting to be returned to her parents and divorced by her husband.

Fistulae have the reputation of being almost impossibly difficult to repair. One contributor believes that there is no such thing as an ''easy' VVF, and that only the occasional generalist with ''golden fingers' can do them. Nevertheless, in one district hospital (Chogoria in Kenya) 15 VVFs were successfully repaired without any failures by a succession of general-duty doctors, all working ''from the book', and with no individual doctor doing more than two. So if you cannot refer VVFs, you may be justified in attempting to repair the smaller, less difficult ones, which do not involve a patient's urethra. If you succeed, she will be immensely grateful. If you get a reputation for repairing them well, patients will come to you from a long way away. As always, learn from an expert, if you can. These are very rewarding patients!

Most VVFs are due to pressure of the child's head during a prolonged labour. The best time to repair them is about 6 to 8 weeks after delivery (one contributor waits 12 weeks), when the slough has separated and the tissues are no longer friable, but before they have had time to become fibrotic. If a patient presents later than this, fibrosis makes the operation much more difficult. As soon as you diagnose a new VVF, keep the patient in hospital and give her salt baths two or three times a day to keep the wound clean.

These fistulae can be repaired abdominally through the bladder, but we only describe the vaginal route. Aim to incise round the edges of the fistula, and free three planes[md]her vaginal mucosa, her bladder mucosa, and if possible a layer of tissue in between them[md]if you can define it. If you can sew up these layers separately, you will probably cure her fistula. See also Primary Mother Care Section 24.3, and the reference below:

Lawson JB, and Harrison K, ''Obstetrics and Gynaecology in in the Tropics'. Edward Arnold. Second edition, expected 1989. Fig. 18-21 REPAIRING A VVF. Note the way in which the patient's legs are held, and how the supports are padded. There is a pillow under her chest, her abdomen is free, she has been intubated, and the table has a 5[de] head-down tilt. It can be more steeply tilted (20[de]) and her legs slightly more flexed than this. ************

VESICOVAGINAL FISTULAE EXPECTANT TREATMENT EXPECT A FISTULA is going to form: (1) When labour is long enough to kill the baby. (2) After craniotomy. (3) When there is gross intrauterine infection (IUI).

IF YOU SUSPECT A FISTULA IS GOING TO FORM insert an indwelling silastic catheter and start continuous closed drainage. Ensure a high fluid intake so as to reduce the risk of infection. Mobilise her early (despite the bag), always keeping the bag below her bladder.

After 7[nd]10 days put her into the Sims' posiiton and examine her anterior vaginal wall with a Sims' speculum. If her bladder is still bruised or necrotic, leave the catheter in and only remove it when later examinations show it is healthy. If you use a latex catheter, change it every 7 days.

If she develops a VVF, continue catheter drainage for 3 weeks, unless the fistula is so big that the balloon falls into her vagina. If it is very small, drain her bladder for 6 weeks. If you can keep her bladder empty, it may close spontaneously.

. If a large area of sloughing tissue causes a persistent foul discharge, debride the dead tissue under general anaesthesia.

If her pubic bone is exposed, it wil be infected (osteitis), so give her a broad spectrum antibiotic and rectal metronidazole 1 g twice daily. Douch her with weak clorhexidine.

As soon as her VVF develops and her vulva is exposed to urine (and especially if she develops an RFV), wash her vulva and perianal area twice daily with soap and water. Twice daily zinc and castor oil ointment will keep her vulva healthy and reduce smell.

PREPARATION. She may well be malnourished, anaemic, tuberculous, or have some chronic bowel disease. Her urinary leak may have caused an ammoniacal dermatitis which has ulcerated. So be sure to restore her general health and make her as fit as you can before you operate. Build up her morale and enthuse your ward and theatre team. If possible, admit her next to a patient who has just had a successful repair.

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ASSESSING A FISTULA WHEN IT HAS FORMED. This is best done 1 to 3 days before the repair, so that you know what to expect and are not obliged to repair a patient immediately after you have assessed her. Explain that you are only going to examine her. If you find that her tissues are not in an ideal state, examine her again later. If they are suitable for operation, anaesthetize her for examination only, and put her into the lithotomy position. You will be able to see large and medium- sized fistulae with a speculum and a catheter. If you have difficulty finding a smaller one, infuse a coloured fluid, such as dilute methylene blue, into her bladder with a catheter and a funnel. Stress incontinence is the main differential diagnosis.

(1) How big is the fistula? (2) How far it is from her urethral orifice? (3) What is the state of the surrounding tissues? Are they soft and friable, or soft and healthy? Mildly, or severely fibrosed? (4) Is her urethra stenosed or obstructed? (5) Is her vagina narrowed, or almost obliterated by scar tissue? (6) Does she seems to have ''lost her urethra'? See Section 20.14.

INDICATIONS FOR BEGINNERS. If you are a beginner, and you cannot refer her, only operate if her fistula is: (1) Less than 1 cm in diameter. (2) More than 2.5 cm from her urethral meatus. (3) Not significantly fibrosed. Otherwise, you are unlikely to succeed until you are much more experienced.

POSITION. This is critical and depends on the skill of your anaesthetist, and your personal preferences as to which way you like to operate. (1) If your anaesthetist is skilled, you can lie her on her front, her thighs abducted as far as possible, and her legs supported in double lithotomy stirrups, as in Fig. 18-21. Bandage her legs to the poles, have her buttocks clear of the table, and an overtable just below her. Tilt her 5[de] head- down, and raise the table to a convenient height to let you see into her vagina. One contributor tilts the table at 20[de] and slightly flexes her thighs over the end of the table so as to stop her slipping down. This is not an easy position to arrange on many theatre tables. (2) If your anaesthetist is less skilled, operate on her while she is lying on her back in the exaggerated lithotomy position, with a steep (30[de]) head-down tilt, her buttocks well over the edge of the table, and her shoulders supported by shoulder rests. This is more difficult, and is like working on the sump of a car without a pit. But it is not too difficult[md]if you get the table high enough with plenty of head-down tilt. Gynaecologists soon get used to it.

ANAESTHESIA. If she is lying prone, use general anaesthesia, intubate her, use relaxants, and control her ventilation. Put a pillow under her chest, and another smaller one under her pubis; make sure that her abdomen is free. Don't rely on spontaneous ventilation, because she will not ventilate adequately.

CAUTION ! No patient should lie prone under general anaesthesia, and be expected to breathe spontaneously. Hypoxia, cardiac arrest, brain damage, and death may follow.

Add a 1 mg ampoule of 1/1000 adrenalin to 100 ml of saline. You will need 10 to 25 ml or more of this solution to infiltrate the tissues round her fistula. It will show up her tissue planes and reduce bleeding.

BLOOD. Cross-match two units.

EQUIPMENT. A knife with a curved No. 12 blade, an ordinary No.10 blade. Sims' specula. Langenbach retractors. Fine 16 cm dissecting forceps, toothed and plain. 12 cm fine curved artery forceps. Two vulsellum forceps. A pair of 20 cm light curved scissors. Two standard needle-holders. A 14 to 16 Ch catheter. A funnel for the catheter. A good sucker, two fine ends for it, and a probe to clear them.

ASSISTANTS. You will need three. (1) An assistant on the right side of the table (viewed from your end), at the level of her abdomen, to hold up her posterior vaginal wall with a Sims' speculum, using both his hands, and resting them against her sacrum if necessary. (2) An assistant immediately on your right. (3) An assistant on your left, with the trolley, to hand you the instruments.

Fig. 18-22 AN EASIER VVF. The patient is lying prone, as in the previous figure. A, the three layers of tissue round her fistula have been separated; the deepest bladder layer is being sutured. B, the intermediate layer is being sutured. C, her vagina is being sutured. Separate the vaginal and bladder layers for at least 0.5 cm. The tissue between them forms an intermediate layer. D, opening the fistula at its margin, as near as possible to the place where her bladder and her vagina meet. E, starting to sew up her bladder. F, her bladder has been sutured, and the sutures from each direction are now about to be tied. G, the intermediate layer has been sutured, and so has the superficial layer. Note that she is prone.

REPAIRING AN EASIER VVF If her fistula is high in her vagina, near her cervix, it is usually easier to suture the first layer transversely, as in Fig. 18-22 and the description below. If it is low (juxta-urethral) near her vesico-urethral junction, suture it longitudinally, as in Fig. 18-22a. Provided she still has a centimetre or two of good urethra, you can repair quite a low fistula.

Place an ordinary Jacques rubber catheter in her urethra, to make sure that you don't close it by mistake. Distend the layer between her vaginal wall, and her bladder, with adrenalin in saline.

Open the fistula at its margin, as near as possible to the place where her bladder and her vagina meet. If necessary, cut within her vaginal epithelium.

If you cannot see the edges of her fistula, pull downwards with a vulsellum forceps applied to the vaginal wall covering her urethra.

Use a scalpel with a No. 12 blade to open up the layer between her vagina and her bladder, keeping near to her vagina. Extend the separation with scissors, using sharp and blunt dissection, until you have separated a good margin, say 1 cm towards her cervix, and 0.5 cm laterally and towards her urethra. This may be difficult, and you may have to cut with the No. 12 blade.

Try to define and dissect an intermediate layer of tissue (her precervical or pubovesical fascia), by separating it from her bladder wall. This may be difficult, if her fistula is large and fibrotic. One contributor considers the separation of an intermediate layer impractical.

She may bleed. If you can suck the blood away adequately, and it does not obscure your vision, accept it. Bleeding will probably stop. If necessary, use a transfixion suture. Avoid diathermy, especially near the walls of her vagina and bladder, because it destroys tissue, and reduces the blood supply.

Suture her bladder, starting at each end and working towards the middle. Using ''0' catgut on a 5/8-circle atraumatic needle, place continuous or interrupted sutures about 3 mm apart. If the fistula is high in her vagina near her cervix (juxta-cervical) it is usually easier to suture the first layer transversely. If it is juxta-urethral, the first layer is best sutured longitudinally.

Check the patency of the repair you have just done by instilling coloured fluid into her bladder. If it leaks, insert more sutures, or take them out and start again.

For the following two layers use reliable ''0' slowly absorbed sutures[md] polyglycolic acid (''Vicryl', best or ''Dexon')[md]or failing these chromic catgut. Close the intermediate layer (if you have been able to define it) with interrupted sutures, and eliminate all dead space. Close her vaginal wall with interrupted sutures. If possible, place the line of sutures transversely. Otherwise place it whichever way the edges lie easiest. Try to arrange the sutures on the three layers so that they don't immediately overlie one another. Check again that the repair does not leak.

CAUTION ! (1) Don't use non-absorbable sutures. (2) Obliterate all dead space. (3) With larger fistulae take care to avoid her ureters.

INSERTING THE CATHETER. A bladder drain is required, which will not press on the repair, as a Foley catheter might, and will not slip out, as would a simple Jacques catheter. Use a big curved post-mortem needle to insert one in the following way.

Push a piece of plastic tubing, or a catheter with its distal end cut off, over a curved post-mortem needle, so that the point of the needle is protected inside the catheter. Introduce this protected needle through her urethra into her bladder. Remove the catheter, leaving the needle in place. Then, using No. 2 monofilament, tie the catheter which is to be used for drainage to the eye of the needle, leaving a length of 12 cm or more free.

Push the needle through her tissues, so that it emerges through her anterior abdominal wall, just above her symphysis pubis. Pull it through with the suture following, so that the end of the catheter lies in her bladder. Tie the suture emerging from her abdominal wall over a button. The catheter should lie freely in her bladder, and not against its wall, and yet not be so]]loose that it can be pulled out.

; Fig 18-22a REPAIRING A DISTAL (juxta-urethral) VESICOVAGINAL FISTULA at the junction of the bladder and urethra. A, mobilize and excise the fistula track. B, the track excised. C, the fistula is low in the vagina, so it is being closed longitudinally in three layers. D, mobilizing and closing the precervical fascia. E, closure of the precervical fascia is complete. F, the vaginal wall has been closed. After Poldratz KC, the Mayo Foundation. Permission requested.

POSTOPERATIVE CARE [s7]FOR A VVF Drain her bladder continuously for 10 (or 12) days. Ideally, use a bag with a non-return valve. Ask the nurses to empty this hourly and sign the chart to make sure that it has been emptied. If the catheter blocks, the repair is in danger of breaking down. It is in the greatest danger of doing so between the 5th and the 8th day. On day 11 spigot and release the catheter 2-hourly. On day 12 do it 4-hourly. If this is satisfactory, remove the catheter and for a day or two check that she passes urine normally.

If she leaks, examine her on a couch in the left lateral position, to find out if urine is coming from the fistula, or from her urethra.

If she leaks from her urethra, this may be because it has been dilated by the catheter. If so, send her home to return in 6 weeks. This urethral incompetence may settle spontaneously. If she is no better, a urethroplasty may be indicated; refer her.

If she leaks through the fistula, continue to drain her bladder for 20 days. It may still close, but this is not very likely. If it does not close in 20 days, remove the catheter, start salt baths again, and reassess her in 2 to 4 weeks. If you cannot refer her, and think you might succeed, try to repair her fistula again, about two months after the original operation. In most series of repairs for large VVFs, about 80% succeed the first time; 50% of the remainder heal the second time when the fistula is much smaller. Marion Sims, the pioneer of these repairs, succeeded for the first time on his thirteenth attempt!

If possible, culture her urine just before you remove the catheter, and if it is infected, give her a 5- to 7-day course of the appropriate antibiotic.

Warn her that if she becomes pregnant again she must have a Caesarean section, her repair may break down and a second attempt at repair will be more difficult.

For difficulties with fistulae, see Sections 18.10, and 18.19D.

Fig. 18-23 SECURING A CATHETER IN THE BLADDER. The purpose of this procedure is to hold a catheter in the bladder, without its pressing on the site of the repair of a VVF. A, covering a post- mortem needle with a catheter. B, introducing the catheter into the bladder. C, the needle in the urethra, the ensheathing catheter removed, and the definitive catheter being tied to the needle. D, the needle being pushed through the abdominal wall. E, the catheter secured with a suture and button.