| disease | Urinary Fistula |
| alias | Urinary Fistula |
Urinary fistula refers to an abnormal passage formed between the reproductive organs and the urinary system, manifesting as fistula disease urine. Common types include bladder-vaginal fistula, urethra-vaginal fistula, and ureter-vaginal fistula (collectively known as urinary fistulas). Reproductive organ fistulas are an extremely painful injury-related condition. Due to the inability to control urination, the vulva is constantly soaked in urine, causing not only physical suffering for women but also significant psychological burden as patients fear social interaction and are unable to participate in productive labor. Strengthening maternal health care, promoting modern childbirth practices, proper management of childbirth, and improving surgical quality can prevent injuries to reproductive organs, thereby significantly reducing the occurrence of reproductive organ fistulas.
bubble_chart Etiology
The vast majority of urinary fistulas are caused by injury. In our country, they are primarily due to difficult delivery injuries, followed by surgical injuries, and less commonly by other injuries or infections.
I. Obstetric Injuries
(A) Prolonged labor: Due to cephalopelvic disproportion, abnormal fetal position, fetal abnormalities, congenital vaginal deformities, or vaginal scars, the fetal presenting part is obstructed in the descent through the small pelvic cavity, leading to prolonged labor, especially the extension of the second stage of labor, which has the greatest impact on the formation of urinary fistulas.
After prolonged labor occurs, the soft tissues such as the bladder, anterior vaginal wall, and urethra are compressed between the pubic bone and the fetal presenting part, gradually leading to edema, ischemia, necrosis, and ulceration, especially during the second stage of labor, where compression for more than 4 hours can lead to tissue necrosis; 5 to 14 days postpartum, the necrotic tissue sloughs off, forming a fistula. If the obstruction occurs at the pelvic inlet, continuous compression on the partially dilated cervix, vagina, fornix, and bladder can damage the bladder and cervix, forming a fistula. Obstruction at the mid-pelvis or outlet, compressing the urethra, bladder neck, and bladder trigone, can lead to damage of the bladder and urethra, forming a fistula. Pelvic outlet obstruction can sometimes cause necrosis and sloughing of the anterior vaginal wall and the entire urethra, leading to vaginal scar stenosis, and urethrovaginal fistula with urethral defect.
(B) Obstetric surgical injuries: Rough handling during obstetric surgeries, using instruments (forceps, cranioclast, vacuum extractor) that directly injure the vaginal wall, bladder, and urethra. Uterine rupture complicated by bladder or ureteral injury, or cesarean section incision tears extending to injure bladder tissue, and/or suturing the ureter or penetrating the bladder wall, if overlooked during surgery and not addressed, can lead to urinary fistulas.II. Gynecological Surgical Injuries Whether performing pelvic gynecological surgeries through the abdomen or vagina, if there is a lack of responsibility, meticulous operation, unfamiliarity with anatomy, coupled with unskilled technique, or blind hemostasis during surgery, especially in cases of pelvic inflammatory disease adhesions, or reproductive organ tumors (uterus, ovary, or broad ligament tumors), uterine prolapse, etc., which alter the anatomical relationships of adjacent pelvic organs, then during total hysterectomy or radical hysterectomy, there is a possibility of injuring the bladder or ureter. If the injury is not discovered, or if discovered but poorly repaired, it can lead to vesicovaginal fistula or ureterovaginal fistula. During radical surgery for cervical cancer, freeing the ureter and injuring its sheath can also lead to ureteral ischemia and necrosis, especially in the presence of postoperative peritoneal infection, more easily causing ureterovaginal fistula. The formation of such fistulas often occurs 7 to 14 days, or 2 to 3 weeks postoperatively. One case in our hospital occurred as late as 48 days postoperatively. Additionally, during vaginoplasty or anterior and posterior vaginal wall repair, vaginal wall cystectomy, and vaginal hysterectomy when separating the bladder, due to unrefined operation or fragile local tissue (such as congenital deformities), or hymenotomy, etc., can injure the bladder and form vesicovaginal fistula.
III. Chemical Corrosive Injuries Placing corrosive drugs in the vagina to treat vaginitis, such as Alum, can corrode and necrotize local tissue, eventually forming a fistula.
IV. Cancer Erosion or Post-Radiation Therapy Injuries Advanced stage cervical cancer or vaginal cancer eroding the bladder, or necrosis and sloughing after irradiation, can form vesicovaginal fistula or urethrovaginal fistula.
V. Others Individual cases of small urinary fistulas are formed by needle puncture injuries to the anterior wall of the vagina. Vaginal trauma, vaginal or bladder subcutaneous nodules, and bladder stones can also induce urinary fistulas. Long-term placement of a uterine pessary in the vagina can lead to incarceration, causing tissue compression, ischemia, necrosis, and resulting in a urinary fistula. There are also cases where sexually transmitted diseases cause ulcers in the vaginal wall, leading to urinary fistulas.
bubble_chart Clinical Manifestations
1. Fistula disease urine: Urine continuously flows out from the vagina.
Urethrovaginal fistula or partial defect of the urethra, located below the internal urethral orifice, where the internal urethral sphincter is not injured, the urination function can still be controlled to some extent, and the phenomenon of fistula disease urine is not yet severe.
Vesicovaginal fistula, vesicourethrovaginal fistula, where the fistula is located at or above the internal urethral orifice, if the fistula is large, all urine flows out from the vagina, and the patient is completely unable to urinate. If the fistula is small and there is granulation forming a flap around the fistula, the patient can often control part of the urine, and only when the bladder is overfilled does urine leakage occur.
High vesicovaginal fistula or vesicocervical (or uterine) fistula, when lying down, there is fistula disease urine, but when standing, there may be no fistula disease urine temporarily.
The characteristic of ureterovaginal fistula is that the patient has fistula disease urine but can also urinate on their own, due to one ureter being injured, urine flows into the vagina, while the other normal ureter transports urine to the bladder and expels it through the urethra. However, if it is a bilateral ureteral injury causing ureterovaginal fistula, the bladder loses its regular urination function completely, and only manifests as vaginal fistula disease urine.
Unilateral ureteroperitoneal fistula, before communicating with the vagina, manifests as fever, abdominal distension and fullness, ascites, etc. The patient can urinate on their own. When the fistula communicates with the vagina, vaginal fistula disease urine occurs, and fever and ascites disappear.
Urinary fistula formed by bladder subcutaneous node or vaginal subcutaneous node has no history of difficult delivery or surgical injury. Bladder subcutaneous node often has long-term bladder infection symptoms, such as frequent urination, painful urination, and pyuria. Fistula caused by vaginal subcutaneous node may have no obvious precursor symptoms. Both conditions may have subcutaneous node lesions or a history of subcutaneous node elsewhere.
Urinary fistula caused by bladder stones often has a history of painful urination, difficulty in urination, and hematuria. During examination, stones protruding from the fistula or stones in the bladder can even be seen or felt (through the fistula or by inserting a metal catheter through the urethra into the bladder).
Those caused by tumors are mostly advanced stage tumors, easily identifiable from history and signs.
2. Infection: The skin of the vulva, buttocks, and inner thighs, due to long-term exposure to urine, develops varying degrees of dermatitis, rash, and eczema, causing local itching and burning pain. If scratched, it can lead to secondary infection, forming boils. Patients with urinary fistula may sometimes have varying degrees of urinary tract infection symptoms. If it is a ureteral fistula accompanied by local ureteral stenosis leading to hydronephrosis, it is more likely to cause infection. Some first form peritoneal membrane and then urine extravasation, complicated by infection, followed by vaginal fistula disease urine, occasionally seen after radical surgery for cervical cancer.
3. Amenorrhea: Possibly due to psychological trauma, about 10-15% of patients with urinary fistula may have secondary amenorrhea or scanty menstruation.
4. Mental distress: Due to urine continuously flowing out from the vagina day and night, regardless of season, wetting clothes and bedding, unable to sleep peacefully at night, and unwilling or unable to go out to participate in social activities during the day, affecting study and productive labor; coupled with some fistula disease urine patients complicating vaginal scar stenosis or partial atresia, losing sexual life and fertility, affecting marital and family relationships, all these bring great mental distress to the patient, leading to depression and secondary amenorrhea.
bubble_chart Auxiliary Examination
(1) Methylene Blue Test: The purpose is to examine small fistula holes in the bladder and vagina that are difficult to identify with the naked eye, multiple small fistula holes, or fistula holes within scars; or to differentiate between bladder-vaginal fistula and ureter-vaginal fistula.
Method: The patient assumes a knee-chest position, a catheter is inserted through the urethra, and a diluted methylene blue solution (2ml of methylene blue added to 100-200ml of saline. If methylene blue is unavailable, a diluted Chinese Gentian violet solution or sterilized milk can be used) is injected into the bladder, and the catheter is clamped. During the injection, the posterior wall of the vagina is lifted to observe if any blue liquid flows out from the anterior wall of the vagina, the anterior fornix, or the cervical os. Blue liquid flowing from the vaginal wall indicates a bladder-vaginal fistula. The number and location of the fistula holes can also be determined. If blue liquid flows from the cervical os or its lacerations, it may indicate a bladder-cervical fistula or a bladder-uterine fistula. If no blue liquid flows out, a ureteral fistula should be suspected. At this point, the catheter can be removed, and if blue liquid quickly overflows from the urethral opening, further testing should be conducted to rule out a ureter-vaginal fistula, and the possibility of stress urinary incontinence should also be considered.
(2) Indigo Carmine Test: The purpose is to diagnose a ureteral fistula. For those who show no blue liquid outflow in the vagina during the methylene blue test, 5ml of indigo carmine can be injected intravenously, and after 5 minutes, observe if any blue liquid flows out from the vagina. If so, a ureter-vaginal fistula can be diagnosed. This method can also diagnose congenital ectopic ureteral orifices located in the vagina.
(3) Cystoscopy: Generally, the above examinations can determine the location, size, bladder capacity, and mucosal condition of the fistula. For high-positioned fistulas, cystoscopy can assist in locating the fistula and clarify the relationship between the fistula and the ureteral orifice, serving as a reference for repair. In well-equipped facilities, even if a fistula is found in the vagina, cystoscopy should still be used to examine the condition of the fistula inside the bladder. This may seem redundant, but it is not, as it can play a decisive role in the diagnosis and treatment of some cases. For example, it has been noted that: ① It can determine the nature of the fistula. In several cases of vaginal fistula, only one fistula hole was found during examination, but multiple fistulas were discovered through cystoscopy; and some fistulas were too high to be treated via the vaginal route; ② It can detect abnormalities inside the bladder, such as inflammation of the bladder mucosa (which can lead to surgical failure), or the presence of stones in the bladder (which can also lead to surgical failure). They found a case where a bladder stone pressing against the cervix caused a urinary fistula, and due to bladder deformity, the ureter was transplanted to the abdominal wall; ③ It can clarify the relationship between the fistula and the ureter. Careful search should be made at the edge of the fistula for the ureteral orifice (observing for paroxysmal urine spraying), and ureteral catheterization can also be performed to clarify the relationship to avoid suturing the ureteral orifice during fistula repair. Ureteral injury during fistula repair is not uncommon and should be guarded against.
For ureter-vaginal fistula, retrograde ureteral catheterization can be performed under cystoscopy. Smooth insertion generally indicates the healthy side, while obstruction on the affected side indicates the location of the fistula and its distance from the bladder. If both bladder-vaginal fistula and ureter-vaginal fistula coexist, diagnosis can usually be clarified through cystoscopy and ureteral catheterization. If the ureteral orifice cannot be found during cystoscopy (often difficult to locate after radical cervical carcinoma surgery), intravenous pyelography can be performed.
(4) Intravenous Pyelography: Helps to clarify the side, location, and renal function of the ureteral injury, as well as whether there is stenosis, dilation, or obstruction in the injured ureter. The method involves intravenous injection of sodium diatrizoate, followed by X-ray imaging of the kidney, ureter, and bladder, with diagnosis based on the imaging results.
Before intravenous pyelography, the patient should first undergo a B-ultrasound to understand the general condition of both kidneys, the renal pelvis, ureters, and bladder. In some cases, retrograde cystography may also be used.
(5) Renogram: The purpose is to understand renal function and the patency of the upper urinary tract. For example, stenosis or obstruction caused by a ureteral fistula can lead to decreased renal function or renal atrophy and loss of renal function on the affected side.
The diagnosis of fistula disease with urinary symptoms is not difficult based on a history of prolonged labor, difficult delivery, surgery, or gynecological surgery, and the discovery of a urinary fistula in the vagina during a gynecological examination. It is important to clarify the cause of the urinary fistula, the nature, location, size of the fistula, and the condition of the surrounding tissues, as this is of great significance for proper management.
I. History: First, a detailed history should be taken to determine the cause of the urinary fistula. If it is due to a subcutaneous node lesion, anti-tuberculosis treatment should be initiated first.
II. Examination: Before examining the fistula, do not instruct the patient to urinate. Instead, ask the patient to urinate during the examination under observation, which helps in detecting small fistulas.
During the examination, to facilitate the exposure of the fistula, the patient can be placed in a knee-chest position. Use a single-blade vaginal retractor or the lower blade of a vaginal speculum to lift the anal wall upwards. In this way, common fistulas such as bladder-vaginal fistula, urethra-vaginal fistula, bladder-urethra-vaginal fistula, along with the entire external genitalia wall and cervix, can be clearly seen under the speculum. The size, location, nature of the fistula, the presence and extent of scar tissue around the fistula, and the condition of the urethra and urethral sphincter should be thoroughly examined. For larger fistulas or those near the bladder trigone, attention should also be paid to the distance between the ureteral orifice and the edge of the fistula (in large bladder-vaginal fistulas, urine spurting from the ureteral orifice can sometimes be seen) and whether there is inflammation, scarring, or stenosis in the vagina. In larger fistulas, the bright red bladder mucosa protruding from the fistula can generally be seen. If the fistula is small or located high and difficult to detect, ask the patient to cough or take a deep breath, and urine and bubbles can often be seen leaking from the fistula; or insert a uterine probe into the urethra while inserting a finger into the vagina to follow the movement of the probe. When the probe reaches the fistula, the two may meet, or the probe may enter the vagina through the fistula, or inject colored liquid into the urethra to observe the site of the fistula disease fluid, and then further confirm with the probe.
Bladder-cervical-vaginal fistula is mostly caused by high difficult delivery or cesarean section complicated by cervical laceration involving the bladder. Examination of the cervix often reveals a laceration or a defect in the anterior lip of the cervix, and urine is seen flowing from the cervical canal while there is no fistula in the anterior vaginal wall. If in doubt, colored liquid can also be injected into the urethra for confirmation.
If it is a bladder-urethra-vaginal fistula, use a probe to check whether the urethra is patent, and whether there is atresia, stenosis, or rupture, and pay attention to the length of the remaining urethra.
bubble_chart Treatment Measures
Surgery is the primary treatment, even for cases caused by cancerous tumors or subcutaneous nodes. Disease cause treatment should be initiated first, and surgical repair should be performed at an appropriate time after the condition improves.
I. Non-surgical treatment: For bladder-vaginal fistulas that occur shortly after childbirth or surgery, and where the fistula is small, a catheter can be placed and kept open continuously. For recently formed ureter-vaginal fistulas, a ureteral catheter can be attempted through bladder endoscopy. If it is a ureter-peritoneal fistula, it is advisable to drain urine through the vagina. In these cases, effective antibiotics should also be administered to control infection, as the fistula may heal naturally. For fistulas caused by subcutaneous nodes or local cancerous tumors, disease cause treatment should be targeted, and small fistulas may contract and heal on their own; for those that do not heal naturally, repair surgery can be performed after 3 to 6 months or longer.
II. Surgical treatment: The majority of fistulas require surgical treatment. The following issues should be noted during surgical treatment:
(1) The timing of surgery should be appropriate: The timing depends on the cause of the fistula. Fresh traumatic fistulas (e.g., from trauma, obstetric surgery injury, gynecological surgery injury) should be treated immediately. For fistulas caused by prolonged labor or chemical injury, surgery should be delayed for 3 to 6 months from the onset of the fistula, when inflammation subsides and tissue healing is better. However, waiting causes patients to suffer from fistula disease and urinary issues, so many medical workers seek faster treatment methods. For example, administering antibiotics and prednisone (5mg, three times daily) for 10 to 20 days after the fistula occurs, followed by fistula repair, has yielded satisfactory results. Therefore, depending on the specific situation, it is not necessary to wait 3 to 6 months uniformly. Surgery must be performed 3 to 7 days after menstruation ends. If the first fistula repair fails, the timing for the second attempt follows the same principles as the first.
For urinary fistulas combined with bladder stones, whether to repair the fistula simultaneously with bladder stone removal depends on the presence of edema or infection in the bladder mucosa. If there is no inflammation, repair can be done simultaneously. Otherwise, it should be delayed until inflammation and edema subside.
For urinary fistulas combined with pregnancy, repair should be done after menstruation resumes postpartum.
(2) Preoperative preparation should be thorough: In addition to a detailed examination of the patient's overall condition and the fistula, as well as mental preparation, the following are necessary:
1. Patients often have dermatitis on the inner thighs and vulva, so a 1:5000 potassium permanganate solution sitz bath should be performed early, followed by zinc oxide ointment application to the affected area. Even without inflammation, a routine sitz bath for 3 days is advisable.
2. For patients with bladder inflammation, bladder mucosal eversion, or bladder stones, penicillin and streptomycin should be administered preoperatively to control infection, and surgery should be performed 1 to 2 weeks after inflammation subsides.
3. Elderly or amenorrheic patients should be given 0.5mg/day of diethylstilbestrol or 3mg/day of diethylstilbestrol diphosphate for 1 week to thicken the vaginal epithelium for easier separation and suturing.
4. Use of cortisone: Adrenal corticosteroids can reduce local inflammation, shrink the fistula, and soften scars. Simultaneous use of antibiotics to control infection can allow earlier fistula repair.
5. Two days before surgery, a low-residue diet should be followed, and enemas should be given the night before and the morning of surgery.
(3) The surgical approach should be appropriate: The choice of surgical approach depends on the nature, location, and size of the fistula, the surgeon's technical proficiency, the use of auxiliary procedures, and the preferred approach of the gynecologist or urologist. For gynecologists, most bladder fistulas are best approached through the vagina, while ureteral fistulas are best approached through the abdomen.
1. Vaginal surgery: As early as over 100 years ago, Sims in the United States was the first to use surgery to cure bladder-vaginal fistula. At that time, he adopted the knee-chest position, pulled the anal wall to expose the surgical field, and used silver wire for suturing. Subsequent practice has proven that most urinary fistulas are most suitable and simple to treat through vaginal surgery. Especially the knee-chest position, which not only easily and clearly exposes the surgical field but also facilitates the surgeon's operation; because the surgery is performed outside the bladder through the vagina, there is less bleeding, relatively shorter time, minimal systemic disturbance, low postoperative morbidity, and fewer reactions. Especially for urethral-vaginal fistula, bladder-urethral-vaginal fistula, and other low fistulas, repair must be done through the vagina; some difficult urinary fistulas, such as those with severe local scarring or large fistula holes, require auxiliary surgery through the vagina, such as using healthy vaginal walls, labia minora or majora flaps for transplantation and filling to improve success rates. If vaginal surgery fails, it can still be repeated multiple times.
For high-position fistulas, such as bladder-cervical (uterine) fistulas, vaginal exposure is difficult and less ideal than the abdominal approach; for large fistulas, if the position of the ureteral orifice is unclear, vaginal repair may risk suturing the orifice closed, making a combined vaginal-abdominal approach preferable; ureterovaginal fistulas are generally not suitable for vaginal surgery; severe vaginal scarring or repeated repairs, where the fistula is difficult to identify or expose via the vaginal route, also warrant a combined vaginal-abdominal approach. Post-radiation urinary fistulas are also suitable for abdominal surgery.
2. Abdominal surgery: There are intraperitoneal extravesical, intraperitoneal intravesical, extraperitoneal extravesical, and extraperitoneal intravesical approaches. The choice depends on the fistula condition. For example, if there is significant scarring around the fistula, the fistula margin involves the ureteral orifice, or the bladder has extensive adhesions making separation difficult, or for complex and difficult urinary fistulas, or when the uterus needs to be removed or has already been removed, an intraperitoneal intravesical approach is preferred; for bladder stones, an intravesical approach is necessary; for repairs requiring the use of omentum, peritoneum, or uterine seromuscular flaps, an intraperitoneal extravesical approach is appropriate.
3. Combined vaginal-abdominal approach: Suitable for large bladder-vaginal fistulas with severe scarring requiring excision; urinary fistulas resulting from failed congenital absence of vagina surgery, etc.
(IV) Intraoperative considerations:
1. Anesthesia selection: Depending on the complexity of the fistula, the difficulty of the surgery, and the duration of the operation, continuous epidural, spinal, or saddle block anesthesia can be chosen. The goal is to ensure adequate relaxation of the perineum and vagina and sufficient duration.
2. Proper positioning is crucial for adequate exposure of the surgical field and ease of operation, and should be determined during preoperative examination. For vaginal repair, two common positions are used: one is the prone frog-leg position, which provides good exposure of the fistula but is less comfortable for the patient and requires a change of position if suprapubic bladder fistula creation is needed; the other is the lithotomy position with elevated hips, which is more comfortable for the patient and provides clear exposure of the surgical field, and does not require a change of position if suprapubic fistula creation is needed, suitable for smaller fistulas with less severe scarring. However, the choice can also depend on the surgeon's preference. For example, if the vagina is more relaxed and the fistula is small, and suprapubic fistula creation is not needed, a flexed lateral decubitus position (often right lateral) can be used. For abdominal surgery, the supine position is used; for combined abdominal and vaginal surgery, the lithotomy position can be used.
3. Good lighting: Ensure the surgical field is well-lit during the operation to facilitate accurate tissue separation.
4. Surgical instruments should have slender handles, and forceps and tweezers should be fine, with sharp scissors and blades to allow for the separation of thin and fragile fistula tissues. Use non-injurious suturing needles. An aspirator should also be available to allow the assistant to promptly clear urine and blood from the surgical field.
5. Suture materials: Both silk and catgut sutures can be used, but they must be of fine gauge, such as chromic catgut 0/3, 0/4. Generally, catgut is used for the bladder mucosa, and catgut or silk for the bladder muscle layer and vaginal mucosa. The advantage of silk is less irritation and good tension, but it needs to be removed if used in vaginal sutures.
6. Freeing and suturing of the tissue around the fistula: Fully freeing the tissue around the fistula and ensuring tension-free suturing are extremely important steps to guarantee the success of the repair surgery. There are two methods for separating the vaginal membrane during vaginal repair. In the past, the vaginal membrane was separated outward from the edge of the fistula by 2-3 mm for about 2 cm, known as the centrifugal separation method. In the past decade or so, an incision is made about 2 cm outside the edge of the fistula, and the separation is done towards the fistula until 2-3 mm remains, known as the centripetal separation method. This separation method requires the vaginal membrane to be inverted and sutured. The centripetal separation method can significantly improve the success rate of repair, especially for complex and difficult fistulas. The reason for success lies in the healthy, scar-free tissue at the separation site of the vaginal membrane, good blood supply, which is conducive to wound healing; the inverted suture replaces part of the bladder wall, making the sutured tissue less tight, facilitating the closure of large fistulas; it can completely avoid injury to the ureteral opening at the edge of the fistula or suture holes; the lateral defect wound of this inverted suture method also requires filling and covering with surrounding tissue, such as the healthy vaginal wall on the side and posterior wall, or labia majora and minora flaps, to strengthen the success of the repair.
In the process of free suturing, it is noteworthy that for fistulas very close to the cervix, even less than 1 cm, it is advisable to perform partial separation from the cervix and then correctly separate the space between the bladder and the cervix. For fistulas closely attached to the pubic bone and pelvis, the bladder should be separated from the bone membrane. For bladder-urethra-vagina fistulas or complete urethral clefts, the author's practice has proven that combining centripetal and centrifugal separation methods, with the suture margin away from the midline of the new urethra and located on the side of the new urethra, is beneficial for success. The success of this free suturing method lies in the first layer using one side of the vestibular mucous membrane for inversion suturing (centripetal separation side) to become the inner wall of the urethra, with the suture line located on the opposite edge of the new urethra; the second layer uses the centrifugal separation method of the mucous membrane tissue on the opposite side to pull towards the opposite side to cover the first layer. This way, it covers the first layer suture, preventing it from overlapping with the second layer suture, including the bladder suture.
Bladder fistula repair suturing is usually done in three layers. The first layer uses a small round needle (or non-injury suture needle) 0/3～0/4 catgut for continuous or interrupted suturing of the bladder mucous membrane and muscle layer (if it is a centripetal separation method, it is the vagina mucous membrane), trying to avoid penetrating the bladder mucous membrane. Suturing should start from the deep or hard-to-expose side. After the first layer is sutured, sterilized milk is injected into the bladder to test for fistula disease. If there is no fistula disease, the second layer (bladder muscle layer or inverted sutured vagina fascia layer) can be sutured with fine silk thread in a mattress interrupted manner to reinforce the first layer suture. The third layer uses 0 catgut to suture the midnight canal mucous membrane. The third layer vagina mucous membrane incision suture should be perpendicular or diagonally crossed with the first and second layer sutures to avoid overlapping of the three layers of sutures, making the layers of tissue not tightly attached, and the vertical crossing is beneficial for strengthening the tension at the repair site, thus benefiting the success of the repair.
7. Selection of auxiliary surgery: Choosing auxiliary surgery is beneficial for improving the success rate of complex and difficult urinary fistulas. Auxiliary surgery can be divided into two categories, one is to expand the surgical field to help expose the fistula, such as perineal side oblique incision, pubic symphysis resection, pubic branch fenestration, etc. The other is to use autologous or allogeneic tissue to replace and fill the defective fistula tissue. Autologous pedicle tissues include: vaginal wall, cervix; large or small labia skin, thigh skin; bulbocavernosus muscle fat pad; gracilis muscle; rectus abdominis anterior sheath; rectus abdominis flap; abdominal membrane; greater omentum; uterine serosa muscle flap; bladder autotransplantation; sigmoid colon, etc. Allogeneic tissues include: fetal bladder, amniotic membrane, and bovine pericardium, etc. The selection depends on the location and nature of the fistula. For low fistulas, vaginal wall, large or small labia skin flaps are mostly selected; for high fistulas, cervical tissue, abdominal membrane, greater omentum, etc. are mostly selected. For bladder-urethra-vagina fistulas, bulbocavernosus muscle fat pad or rectus abdominis flap should also be added to reinforce the bladder neck; for complete vaginal defect or severe scarring (after scar removal), uterine serosa muscle flap or sigmoid colon is preferred.
8. Suprapubic bladder fistula: For difficult urinary fistulas and urethral reconstruction, it is advisable to create a fistula, which is beneficial for fistula healing.
9. For bladder stones partially exposed in the fistula, they should not be removed through the vagina, but should be removed by incising the bladder and then repaired.
(5) Strengthening postoperative care: It is an important part of ensuring the success of the surgery.
1. Bladder drainage should be continuously smooth to facilitate wound healing. Bladder fullness can break the suture, leading to surgical failure. If there is urine leakage early after surgery, it may come from the urethra or a small crack, do not give up hope of success and remove the catheter, many cases can still heal in the end, do not rush to do a vaginal examination.
The time for placing the catheter can be determined according to the size of the fistula. If the fistula is very small, it can be removed 3-5 days after surgery, for large fistulas, it can be extended to 12-14 days. A very small number of people believe that there is no need to place a catheter at all, and take the approach of self-urination after surgery. The reason is that it is easy to cause ascending infection, the catheter directly stimulates the repaired wound in the bladder, and over time, urine salts solidify to form stones, affecting the success of the surgery.
Currently, drainage is still commonly used, but regardless of the type of bladder drainage employed, it is essential to keep the drainage tube unobstructed. During the period of indwelling catheterization, bladder irrigation is generally not required. However, in cases of hematuria or significant sediment, if the catheter is blocked, a small amount (10-20ml each time) of sterile saline or a 1:5000 solution of nitrofurazone can be used for low-pressure irrigation until the flow is restored. Some routines include administering Chinese medicinals such as Plantain Seed and Honeysuckle decoction orally to clear heat and promote diuresis. Patients are encouraged to drink plenty of fluids. In the immediate postoperative period, fluid intake should be sufficient, around 2500-3000ml/day, and thereafter, patients are encouraged to drink more water.
2. Maintain perineal cleanliness: The perineum and external urethral orifice must be wiped twice daily with a 1:2000 solution of benzalkonium bromide to prevent ascending infections.
3. Postoperative positioning: Try to adopt a prone or lateral position to reduce the risk of infection from urine soaking the fistula site. However, if the patient finds it difficult to maintain one position, lying flat is also acceptable. The key is to ensure the catheter remains unobstructed.
4. Routine use of antibiotics for 2 to 3 weeks, with estrogen supplementation for elderly patients.
5. Postoperative diet should consist of liquid and residue-free semi-liquid foods for 5 days. On the fourth day, liquid paraffin or Intestine-Moistening Pill can be administered to ensure daily bowel movements.
6. Upon discharge, it should be explained that sexual intercourse and vaginal examinations are prohibited for 3 months, as they may cause the repaired urinary fistula to rupture. If pregnancy occurs later, early hospitalization must be emphasized, and a cesarean section should be performed. For those who already have children, especially those with difficult fistula repairs, weak local tissues, or narrow pelvises, contraceptive measures should be taken or sterilization should be performed during the repair along with seasonal epidemic prevention.
Strengthening perinatal care and continuously improving the quality of obstetrics and gynecological surgical techniques can prevent the majority of urinary fistulas.
Birth injury is the main cause of urinary fistula in developing countries. In China, especially in rural areas, it is essential to strengthen the construction of the three-tier maternal and child health care network, enhance the professional skills of maternal health care personnel, improve the systematic management of pregnant and parturient women, vigorously promote scientific childbirth, and increase the rate of hospital childbirth. Comprehensive emphasis should be placed on family planning to avoid unplanned pregnancy and childbirth. Prenatal check-ups should be conscientiously conducted to detect narrow pelvis, deformities, and abnormal fetal positions early and correct them promptly, with early hospital admission for any abnormalities. Difficult pregnancies and childbirths should be promptly referred to experienced doctors or sent to well-equipped hospitals for management. Strengthening the observation of the labor process is crucial; prolonged labor must be investigated and managed early. The second stage of labor should not be excessively prolonged, generally not exceeding 3 hours for primiparas and 2 hours for multiparas; surgical intervention should be considered early for those with clear surgical indications. Prolonged pressure of the fetal head on the vagina often requires routine postpartum catheterization, which is beneficial for preventing urinary fistula. Obstetric surgery should be performed cautiously and meticulously; when using sharp instruments or passing bone fragments from decapitation or dismemberment through the vagina, the vaginal wall must be protected. Postoperative routine examination should check for injuries between the reproductive tract and urinary tract, with immediate repair if found. For lower uterine segment transverse cesarean section, the right rotation of the uterus should be corrected first to avoid incision tearing. For those with laceration and bleeding, it is advisable to use oval forceps to clamp and stop the bleeding first, then push aside the surrounding tissues of the uterine incision to clearly expose the edges of the incision before suturing to stop the bleeding, which can avoid suturing the ureter and causing a fistula. In cases of uterine rupture, before suturing, attention should be paid to whether there is bladder injury (if identification is difficult, inject methylene blue into the bladder), or bladder injury involving the ureteral orifice (if necessary, open the bladder for retrograde ureteral catheterization).
For patients cured of urinary fistula, cesarean section is recommended for subsequent deliveries.
