For the obstetric fistula, several consensus meetings have been held on the optimal closure of the fistula. Absorbable sutures 2/0 are recommended. Strong bites in the detrusor and serosal layers are necessary to close the fistula, but there is no need to close the urothelium separately. A single layer of separate sutures of 4–5 mm apart is sufficient to close the fistula. After closure, the bladder should be filled with blue dye to check for watertight closure. Eventually, supporting sutures can be used to stabilize the bladder neck. A Martius flap is optional in most cases [3].

Fistulas involving the bladder neck area or mid-urethra have a higher risk of persisting incontinence, despite a successful closure of the fistula. The urethral support mechanisms and the external urethral sphincter might be damaged as a consequence of the fistula, fibrotic process, or fistula repair. The larger the fistula, the more vaginal scarring and the smaller the bladder capacity, the higher the risk for postoperative incontinence. The surgical principles in these cases are the same as for other fistulas, but some additional measures can be taken. The urethral length should be maintained as much as possible. If the urethral length is less than 2.4 cm or if the urethral defect is more than 4 mm, an incontinence procedure should be added. If performed, postoperative incontinence can be reduced by approximately 50 %. Either a sling procedure can be added or a bladder neck suspension can be performed. For the sling procedure, only autologous material should be used. A sling can be created from fibromuscular tissue in the lateral vaginal wall or can be constructed out from the rectus or fascia lata. In the bladder neck suspension, non-absorbable sutures are used to suspend the bladder neck area in a fixed position [4].

Bladder drainage should be continued for 10–14 days, in most cases. In smaller fistulas that were easy to repair, shorter catheterization periods might be possible. When draining the bladder, silicone catheters are preferred since these have a larger internal diameter for the same external diameter and are less likely to be blocked by blot clots. A high fluid intake should be maintained to prevent clot formation. There is no need for antibiotics during the catheterization periods. Nursing staff should be trained and supervised adequately to ensure that catheters are not blocked, which could lead to a rupture of the fistula repair.

Abdominal fistula repair can be done open, laparoscopically, or robotically. Extravesical and transvesical techniques have been described. The principles remain the same: identify the fistula, separate the bladder wall from the vaginal wall, and mobilize the fistula well enough to allow tension-free closure. Omentum can be used as interposition material.