Sound anatomic knowledge, adequate operating exposure, meticulous technique, and surgical experience are essential to avoid surrounding organ injury during pelvic surgery. The lower gastrointestinal and urinary tracts are closely related to the female reproductive organs, and disease processes, anatomic distortion, and adverse operating conditions can increase their injury risk.
Iatrogenic damage to the lower urinary tract is common, and up to 75 percent of ureter or bladder injuries sustained during gynecologic surgery occur during hysterectomy (Walters, 2007). Most injuries have no antecedent risk factors, but high-risk elements are ideally sought preoperatively. These include compromised visibility from large pelvic masses, hemorrhage, pregnancy, obesity, inadequate incision, suboptimal retraction, and poor lighting. Additionally, scarring or anatomic distortion from cervical and broad ligament leiomyomas, malignancy, endometriosis, pelvic organ prolapse, and prior pelvic infection, surgery, or radiation are risks (Brandes, 2004; Francis, 2002).
Patients who sustain surgical injury to the bladder or ureter suffer significantly greater morbidity. In one case-control study, women with injury to the lower urinary tract during abdominal hysterectomy had significantly greater operative time, estimated blood loss, blood transfusion rates, febrile morbidity, and postoperative stay length than their respective controls (Carley, 2002).
Cystotomy is common and complicates approximately 0.3 to 11 per 1000 benign gynecologic surgeries, especially urogynecologic procedures and hysterectomy (Gilmour, 2006; Mathevet, 2001). In sum, depending on the procedure, the bladder may be at greater risk during: (1) initial abdominal entry when incising the anterior parietal peritoneum, (2) dissection within the space of Retzius, (3) vaginal epithelium dissection during anterior colporrhaphy, or (4) hysterectomy when dissecting in the vesicocervical space, entering the anterior vagina, or suturing the vaginal cuff. With hysterectomy, bladder injury traditionally has been associated more often with the vaginal hysterectomy, but some data suggest that laparoscopic procedures pose the greatest risk (Francis, 2002; Frankman, 2010; Harris, 1997). Preventatively, clear identification of the bladder, gentle retraction, meticulous surgical technique, sharp dissection, and maintenance of a drained bladder intraoperatively are standard principles.
Cystotomy is suspected if a Foley bulb, bloody urine, or urine leaking into the operative field is seen. During laparoscopy, the Foley bag may also distend with gas from the pneumoperitoneum. For diagnosis, retrograde instillation of sterile milk through a catheter confirms injury and delineates its full extent. This is superior to methylene blue and indigo carmine dyes, as infant formula does not stain surrounding tissues and is readily available. In addition, small defects can be difficult to identify and repair if the tissues surrounding the defect become dye stained. Prior to repair, cystoscopy is indicated for any bladder base injury to assess ureteral patency. In addition, the full extent of injury can be defined, and the bladder can be evaluated for additional injuries or intravesical sutures. If bladder distension cannot be maintained during cystoscopy or if the patient is not in dorsal lithotomy, the ureteral orifices can also be evaluated grossly through the cystotomy site. If the cystotomy is small, suprapubic teloscopy, which is described in Chapter 45, is also an option, or the cystotomy can be extended to allow evaluation.
Repair during the primary surgery is preferred and lowers risks of later vesicovaginal fistula formation. Principles of repair include injury delineation; wide mobilization of surrounding tissues; tension-free, multilayered, watertight closure; and adequate postoperative bladder drainage (Utrie, 1998). Suture identified in the bladder is cut, as persistence can lead to cystitis, stone formation, or both. Needle-stick and subcentimeter lacerations can be managed conservatively. Larger defects may be closed in two or three layers with a running stitch using 3-0 absorbable or delayed-absorbable suture (Fig. 40-32). The first layer inverts the mucosa into the bladder, and subsequent layers reapproximate the bladder muscularis and serosa. In the area of the trigone, the ureters are typically stented first, and the repair may be performed with interrupted sutures to avoid ureteral kinking (Popert, 2004). Postoperatively, continuous bladder drainage is continued for 7 to 10 days (Utrie, 1998). Evidence is conflicting regarding the use of prophylactic antibiotics for the expected duration of catheterization, and thus remains at the provider’s discretion.
Cystotomy repair. The primary layer inverts the bladder mucosa with running or interrupted sutures of 3-0 delayed-absorbable or absorbable suture. Second and possibly a third layer approximate the bladder muscularis to reinforce the incision closure. (Reproduced with permission from Cunningham FG, Vandorsten JP, Gilstrap LC: Operative Obstetrics, 2nd ed. New York: McGraw-Hill; 2002.)
The female urethra is rarely injured during gynecologic surgery, but cystoscopy, urethral diverticulum repairs, antiincontinence operations, and possibly anterior colporrhaphy are at-risk procedures. Repair is completed with 3-0 or 4-0 absorbable suture in an interrupted fashion and in multiple layers, if possible. Similar to cystotomy, a Foley catheter is typically placed postoperatively for 7 to 10 days, with antibiotic prophylaxis provided at the surgeon’s discretion (Francis, 2002).
This is uncommon in benign gynecologic surgery, and the incidence approximates 0.2 to 7.3 per 1000 surgeries. For hysterectomy, the highest rate of ureteral injury is linked with laparoscopic hysterectomy, and the lowest with vaginal hysterectomy (Gilmour, 2006). Other associated procedures include operations for pelvic organ prolapse, incontinence, malignancy, or endometriosis (Patel, 2009; Utrie, 1998).
The ureter is 25 to 30 cm long, and its anatomy is described in Chapter 38. Gynecologic ureteral injury typically occurs in the distal third and includes transection, ligation, kinking, and crushing (Brandes, 2004; Utrie, 1998). Trauma to the outer sheath can also disrupt ureteral blood supply. Of these, the ureter more often is transected or kinked, and each accounts for approximately 40 percent of injuries. During hysterectomy, the most common trauma site is at the level of the uterine artery and accounts for 80 percent of injuries (Ibeanu, 2009). The ureter is also vulnerable near the pelvic brim during adnexectomy and at the distal uterosacral ligaments. Mechanisms of injury include clamping or suturing with the ureter poorly visualized. Thermal insult or devascularization may lead to stricture or leak.
Injury prevention measures include preoperative risk evaluation and if indicated, intravenous pyelography (IVP) or computed tomography (CT). Ureteral stenting assists with intraoperative recognition but does not necessarily prevent injury. As with bladder injury, the best prevention is sound intraoperative technique and direct visualization of the peristalsing ureter. Also, the ureter may be felt to “snap” if palpated and stretched along its course on the broad ligament’s medial leaf. However, vessels, adipose tissue, and peritoneal folds can mimic this.
Iatrogenic injury ideally is diagnosed early, as immediate repair is associated with improved outcomes and less patient morbidity (Neuman, 1991; Sakellariou, 2002). Damage may be seen directly or identified during intraoperative cystoscopy. Intravenous administration of indigo carmine or methylene blue can aid cystoscopic evaluation, with observation of blue-stained urine from the ureteral orifices. This is described fully in Section 45-1 of the atlas. However, use of the latter may increase given current indigo carmine shortages. With these dyes, blue effluent is usually seen in 5 to 10 minutes. Failure to see dye after 30 to 40 minutes mandates further evaluation with either IVP or ureteral catheterization. Unfortunately, normal-appearing findings at cystoscopy do not guarantee ureteral integrity, as nonobstructive, partially obstructive, or late ureteral injuries may be unrecognized.
Diagnosing injury shortly after surgery is challenging, as patient symptoms may be attributable to other causes. Thus, thorough patient evaluation and a high clinical suspicion are crucial. Renal damage may begin 24 hours after obstruction and can be irreversible in 1 to 6 weeks (Walter, 2002). Symptoms usually develop about 48 hours after surgery, and fever, abdominal pain, flank pain, and watery discharge may be among these. Findings can include leukocytosis, elevated blood urea nitrogen level, and ileus. Prolonged skin or vaginal drainage suggests a urinary leak, and high creatinine levels in these fluids are diagnostic of urine. Serum creatinine measurement may or may not be helpful. In one retrospective study of 187 patients, a 24-hour postoperative change <0.3 mg/dL from preoperative levels had a specificity of 98 percent and negative predictive value of 100 percent in confirming bilateral ureteral patency. Because an increase >0.2 mg/dL has been associated with obstruction, the authors recommended repeating a creatinine measurement and renal imaging for persistent elevation above this level (Walter, 2002). With elevated serum creatinine levels, calculation of the fractional excretion of sodium (FENa) or assessment of urine sodium levels may also help clarify the renal injury source as prerenal, intrarenal, or postrenal, as described in Chapter 42.
Sonography, CT, or magnetic resonance (MR) imaging will help identify hydronephrosis, urinoma, or abscess. Lack of contrast in the distal ureter on delayed CT images confirms total obstruction (Armenakas, 1999). IVP can also help localize injury. However, IV contrast can be nephrotoxic, and thus CT with contrast may be a less than ideal choice for those with already elevated creatinine levels. Retrograde pyelography with fluoroscopic guidance and attempted retrograde ureteral stent placement can be considered in cases where suspicion remains high, and IVP is contraindicated or has equivocal findings. All of these imaging modalities can be used to diagnose injury in both the early and late postoperative periods.
The best repair method depends on the location, extent, time from surgery, and mechanism of injury. Expert assistance from a urogynecologist, gynecologic oncologist, or urologist may be prudent. The ureter can be repaired by stenting, reimplantation, or end-to-end reanastomosis. For low-grade sheath injuries from clamping or suturing, removal of the insult and stent placement may be sufficient. For incomplete obstruction or injury identified postoperatively, stenting alone can resolve injuries in up to 80 percent of cases. For more extensive injury, either reimplantation or reanastomosis is performed (Utrie, 1998).
Reimplantation, namely, ureteroneocystotomy, is preferred for injuries within 6 cm of the bladder. Uncommonly with this, if the ureter is short, a psoas hitch, that is, mobilizing the bladder and attaching it to the psoas muscle tendon, may be necessary to bridge the gap and relieve tension on the repair. An alternative to the psoas hitch is a Boari flap. In this procedure, the bladder ipsilateral to the injury is mobilized, and a pedicle of anterior bladder wall is fashioned into a tube to bridge to the ureter.
For injuries greater than 7 cm from the bladder, ureteral reanastomosis, that is, ureteroureterostomy, is preferred. Rarely, transureteroureterostomy is needed for a more proximal injury or one in which the bladder cannot be mobilized. With this procedure, the injured ureter is tunneled across and connected to the healthy ureter.
Little evidence guides the decision for reoperation in the early postoperative period. Intraoperatively, tissues are in their best condition, and the likelihood for successful repair is great. However, most iatrogenic injuries are recognized after a delay and tend to be complex (Brandes, 2004). In general, reexploration within the first few days appears to be well tolerated, leads to good outcomes, and is not technically difficult (Preston, 2000; Stanhope, 1991). Firm recommendations regarding reoperation beyond this early postoperative period are lacking, but reexploration 2 to 3 weeks after initial surgery is difficult due to inflammation, fibrosis, adhesions, hematoma, and distorted anatomy (Brandes, 2004).
For delayed diagnoses, retrograde stenting is unsuccessful in 50 to 95 percent of cases and recommended only for certain low-grade injuries (Brandes, 2004). Occasionally, an antegrade stent can be placed percutaneously, which will avoid the need for laparotomy, provided there is no ureteral leak or stricture. More extensive damage, such as complete transection, cannot be easily stented and is more appropriately repaired by definitive surgery. When diagnosis is significantly delayed, urinary diversion with a percutaneous nephrostomy (PCN) and later repair is preferred. For some low-grade lesions, such as ligation with absorbable suture, proximal urinary diversion by PCN may allow spontaneous healing without further surgery. In addition, PCN diversion may be used as a temporizing measure for patients temporarily unfit for surgery (Preston, 2000).
Lower urinary tract injury is poorly detected by direct visualization, and rates range from 7 to 12 percent for ureteral trauma and approximate 35 percent for bladder damage (Vakili, 2005). To increase early diagnosis, universal intraoperative cystoscopy has been advocated, and detection rates are near 96 percent (Ibeanu, 2009; Vakili, 2005; Visco, 2001). Proponents argue that the procedure is cost-effective, carries minimal risk, and prevents both postoperative morbidity and liability. Opponents cite overall low rates of injury, imperfect detection rates, increased costs, credentialing problems, and a need for training (Patel, 2009). Using a decision analysis model, one study estimated that routine cystoscopy was cost-effective when ureteral injury rates were above 1.5 percent for abdominal hysterectomy and 2 percent for vaginal and laparoscopically assisted hysterectomy (Visco, 2001).
Cystoscopy is currently indicated for urogynecologic procedures, but there are no strict recommendations for other routine gynecologic procedures, including hysterectomy (American College of Obstetricians and Gynecologists, 2013; Patel, 2009). At present, the decision remains at the surgeon’s discretion. Some have elected selective cystoscopy, or cystoscopy restricted to patients with risk factors or when intraoperative events make injury more likely.
Injury to the bowel infrequently complicates gynecologic surgery, and rates are <1 percent (Harris, 1997; Makinen, 2001). A traumatic breach during dissection is the most common, particularly if the bowel wall is abnormally fixed by adhesions (Mathevet, 2001; Maxwell, 2004). Additional risks include reduced organ mobility from Crohn disease or diverticulitis, laparoscopic trocar or Veress needle insertion, diathermy use, and anterior abdominal wall entry during laparotomy.
For the gynecologic surgeon, prevention and injury recognition help avoid serious postoperative sequelae. Strict adherence to surgical principles with sharp dissection for adhesions, gentle tissue handling, adequate exposure, light retraction, and sparing use of diathermy near hollow organs is key. Entering through prior abdominal incisions, dissection proceeds methodically in layers. Alternatively, a separate incision or extension of the existing one to an area that has not been previously opened can be considered. After any extensive pelvic dissection, the bowel is systematically inspected along its entire length to detect serosal defects and unrecognized perforation. At suspected sites, the bowel is scrutinized for mucosal eversion and content leakage. Evaluation is gentle to avoid additional damage.
Management of enterotomy depends on the site and size of injury, surgeon skill, degree of blood supply compromise, and time of recognition. With the small intestines, serosal defects may be either left alone or reinforced with small-gauge absorbable suture (Maxwell, 2004). Short small-intestine enterotomies may be repaired in layers using fine absorbable suture. During repair, rubber-shod clamps are placed across the intestinal lumen on either side of the wound to prevent content spill. To avoid narrowing of the bowel lumen, the suture line should lie transverse to the normal axis of the intestine (Stanton, 1987). Postoperative antibiotics are typically not required.
Large-bowel injuries increase the risk of fecal peritonitis, sepsis, and poor wound healing. Serosal defects and small lacerations may be managed similarly to those of the small intestine. For more extensive injuries or fecal soiling that may require resection, diversion, or complicated repair, consultation with a gynecologic oncologist or colorectal surgeon is often indicated. Broad-spectrum antibiotic prophylaxis is provided for the next 24 hours in these cases. In general, for both small and large intestinal injuries, early feeding is acceptable and not associated with repair site complications (Fanning, 2001).
Rectal injury occurs most commonly during vaginal surgery, especially during posterior colpotomy or posterior colporrhaphy. These injuries are typically midline, extraperitoneal, and less than 2 cm. Postmenopausal status, prior posterior colporrhaphy, or pathology that obliterates the cul-de-sac or limits organ mobility increases injury risk (Hoffman, 1999; Mathevet, 2001). Prevention centers on careful examination under anesthesia to detect cul-de-sac fullness or uterine immobility, sharp dissection with the aid of a guiding rectal finger, and vasoconstricting agent use to reduce obscuring operative field bleeding.
Rectal injury may be extraperitoneal or intraperitoneal, and rectal examination will typically detect the injury and delineate its borders. Minor intraperitoneal injuries with minimal or no contamination can be repaired primarily in layers as described previously. Larger injuries with gross soiling may require expert consultation. Broad-spectrum antibiotic prophylaxis is provided for the next 24 hours in these cases.
Low extraperitoneal rectal injury during vaginal surgery in a healthy patient can be repaired primarily and rarely requires a diverting colostomy or abdominal repair. Repair is accomplished transvaginally using two to three layers of fine absorbable suture. The peritoneum may be used as an additional layer for injuries near the peritoneal reflection. During repair, a digit in the rectum exposes the defect, tissues surrounding the defect are mobilized, the site is copiously irrigated, and appropriate antibiotic prophylaxis is provided for 24 hours (Hoffman, 1999). In general, small (<2 cm) rectal injuries recognized and repaired at the time of vaginal surgery tend to heal well without complications or fistula formation (Mathevet, 2001). Diet can be advanced as tolerated, but a stool softener is recommended once the patient is taking solid foods (Hoffman, 1999).