Cesarean delivery is currently the most frequently performed major surgical procedure for women in the United States. More than 1 million procedures are completed each year (MacDorman, 2008). Associated mortality rates are low with this operation, but it has higher maternal morbidity rates during both initial and subsequent pregnancies. In many instances, associated risks for urinary tract and bowel injury are identified preoperatively, and preemptive steps are taken. However, in other cases, undiagnosed adhesive disease, hysterotomy laceration, or unplanned hysterectomy can increase adjacent organ trauma. Thus, all obstetricians ideally are able to recognize these injuries. Simple repairs can be completed in most cases by a generalist. However, more extensive damage often requires consultation with surgeons skilled in these more difficult repairs. Importantly, differentiation between the two is essential to maximize patient outcome.

Injury to the urinary tract during cesarean delivery is infrequent. Rates range from 0.08 to 0.94 percent for bladder injury and from 0.027 to 0.09 percent for ureteral injury (Eisenkop, 1982; Rajasekar, 1997; Tarney, 2013). Virtually all bowel injuries associated with childbirth are to the anal sphincter and lower rectum during vaginal deliveries. These injuries and their repair are described and illustrated in Chapter 20 (p. 325). Bowel injuries during cesarean delivery are rare, and estimated rates range between 0.04 and 0.08 percent (Davis, 1999).

From 1996 to 2009, the cesarean delivery rate increased from 20.7 percent to 32.9 percent of all births (Osterman, 2014). As described in Chapter 25 (p. 404), these numbers reflect several modifiable factors. Among these are higher labor induction rates, lower operative vaginal delivery rates, emergence of cesarean delivery on maternal request, and a decline in rates of vaginal birth after cesarean (VBAC). In fact, 90.8 percent of women with low-risk pregnancies currently undergo repeat cesarean delivery (Office of Disease Prevention and Health Promotion, 2014). Logically, these trends correspond with an increase in the frequency of urinary tract and bowel injuries (American College of Obstetricians and Gynecologists, 2015; Osterman, 2014).

Several specific patient or pregnancy characteristics raise the risk for gastrointestinal or urinary tract injury and are listed in Table 28-1. In general, these attributes can be divided into those that are identifiable preoperatively and those that are found intraoperatively. The most consistently reported risk factors for injury include prior cesarean delivery, prior pelvic surgery, pelvic adhesions, emergent delivery, cesarean hysterectomy, and cesarean delivery during labor (Davis, 1999; Eisenkop, 1982; Phipps, 2005; Tarney, 2013). Extension of the uterine incision, either by direct trauma or with attempts to control bleeding, can be associated with adjacent ureteral injury. Also, uterine artery ligation used to control postpartum hemorrhage places the ipsilateral ureter at risk. Prior myomectomy, multiple cesarean deliveries, or pelvic surgery that is associated with bowel adhesions to uterus, anterior abdominal wall, or other pelvic structures increases the potential for intestinal injury (Davis, 1999; Eisenkop, 1982). This risk may be especially likely for women with prior classical cesarean delivery. These cases often yield dense adhesions between the anterior abdominal wall and anterior uterus. Thus, an understanding of these preoperative risk factors permits an obstetrician to anticipate and ideally mitigate many of these aspects that lead to organ injury.

Compromised surgical exposure is the unifying thread among most known risk factors for adjacent organ injury (Francis, 2002). Intraoperative risk is further compounded by the altered anatomy of pregnancy and the frequently urgent, abrupt, and stressful circumstances surrounding surgical intervention (Chaliha, 2002; Yossepowitch, 2004). The wise surgeon will assess risk factors to guide decisions regarding the best anesthetic, laparotomy incision type, and surgical assistant to minimize the threat to the patient. Moreover, during emergent cesarean delivery, calm, logical, and controlled decision making should replace reactions spawned by “the heat of the moment.” Surgeons performing obstetric surgery should take every precaution to prevent injuries through identification of risk factors. When prevention is not possible, heightened awareness and vigilance, with recognition and repair of injuries to the gastrointestinal and urinary tracts, substantially reduce patient morbidity.

Damage to the bladder or ureter is rare during vaginal delivery. In these instances, such damage is most often associated with uterine scar rupture or instrumental deliveries. As one example, with vaginal sidewall laceration, the vaginal wall overlying the ischial spine is a frequent site. The distal ureter can be damaged from extension of the laceration. In addition, sutures required to repair a sidewall laceration can ensnare the ureter (Kattan, 1997).

During cesarean delivery, the anatomic and physiologic changes that develop during pregnancy place the urinary tract at greater risk for injury. First, as the uterus enlarges, the bladder is drawn upward anteriorly and becomes more of an abdominal organ by the third trimester (Chaliha, 2002). Second, the left ureter may be more prone to injury as uterine dextrorotation brings it more ventral (Davis, 1999). The left ureter is also more difficult to identify, as the physiologic hydroureter of pregnancy is more marked on the right (Rasmussen, 1988). Additionally, the left ureter is frequently hidden beneath the sigmoid colon. Last, marked dilatation of the ovarian vessels places the ureter at greater risk for injury during retroperitoneal dissections and isolation of the infundibulopelvic ligament.

Fortunately, urinary tract injury is infrequent, and intraoperative recognition with immediate repair results in little patient morbidity (Blandy, 1991; Brubaker, 1991; Faricy, 1978; Neuman, 1991). However, if unrecognized, these injuries can lead to significant sequelae, including renal damage and genitourinary fistulas (Yossepowitch, 2004).

Obstetric facilities are equipped for vaginal and abdominal deliveries and may lack necessary equipment for endoscopic and urologic assessment of the urinary tract (Yossepowitch, 2004). Labor and delivery operating tables may not be designed for intraoperative radiography, and the operating time needed to mobilize equipment and personnel can be significantly prolonged (Davis, 1999). Therefore, in cases with a greater chance for these complications, preemptive consultation with a urogynecologist, gynecologic oncologist, or urologist and with labor and delivery nursing staff is prudent to aid evaluation and management of these injuries.

Urethral Injuries

In the past, episiotomy was routinely performed during vaginal or instrumental delivery. However, midline episiotomy increases the potential for external anal sphincter or rectal tears. Thus, practice patterns now favor only selective use of this perineal incision. As a result, distention forces during many vaginal deliveries are directed anteriorly. And, anterior inner labial lacerations that extend into the urethral meatus are more common in women in whom an episiotomy is avoided.

In most cases of urethral injury, only the distal meatus is torn and solely at one point around its circumference. Periurethral tissue is extremely vascular in pregnancy, and bleeding can be brisk. However, this same vascularity is responsible for the rapid healing seen with these tears. Thus, for repair, a fine-gauge absorbable suture is appropriate, and interrupted stitches are positioned to reestablish the urethral meatal ring. One option is 3-0 chromic gut suture. This same suture type can also be used for concurrent adjacent inner labial laceration approximation.

Urinary retention can follow these lacerations. Therefore, heightened surveillance for this is reasonable. Foley catheter insertion is needed only to relieve urinary retention or to allow careful urine volume measurement for associated indications such as hypovolemia.

For perineal care, a cool pack applied to the area may help reduce edema and discomfort during the first 24 hours. Most women also appear to gain relief from periodic application of a local anesthetic spray. Beginning approximately 24 hours after delivery, moist heat as provided by warm sitz baths can be used to reduce local discomfort. Mild analgesics can be provided as needed.

Bladder Injuries

Incidence and Risks

The bladder is the most frequently injured organ during pelvic surgery. Of risks, women undergoing repeat cesarean delivery carry a more than fourfold greater risk for bladder injury than those undergoing primary surgery (Phipps, 2005). Adhesion formation after primary cesarean ranges from 46 to 65 percent and appears to be a significant etiologic factor for cystotomy during a repeat procedure (Tarney, 2013). Intuitively, the cystotomy rate rises steadily with an increasing number of cesarean deliveries. These rates range from 0.13 percent with the first cesarean up to 4.5 percent with the sixth cesarean delivery (Silver, 2006). In one study, unsuccessful trial of labor after cesarean (TOLAC) was associated with the highest incidence of bladder injury compared with successful vaginal birth after cesarean (VBAC) and with elective repeat cesarean delivery (Cahill, 2008). In addition, peripartum hysterectomy is associated with a ninefold greater cystotomy rate compared with hysterectomy for nonobstetric indications (Wright, 2010).

The bladder is lacerated most often during blunt or sharp dissection in the vesicouterine space to create the bladder flap. The second most frequent circumstance is during peritoneal cavity entry at laparotomy (Phipps, 2005; Rahman, 2009). The dome is lacerated in 95 percent of cases, and injury at the trigone makes up the remainder. The average laceration length is 4.2 cm but ranges from 1 to 10 cm (Phipps, 2005). Recognition is the most important prognostic factor of bladder injury, and failure to diagnose urinary tract trauma during surgery may lead to vesicovaginal, vesicouterine, or ureterovaginal fistula.

Cystotomy Diagnosis

Fortunately, bladder injuries are usually detected intraoperatively and most often after delivery of the newborn and repair of the uterine incision. Intraoperative findings that often indicate bladder injury include visual extravasation of urine, appearance of the Foley bulb, gross hematuria, and visible detrusor laceration.

Instillation of sterile milk through a Foley catheter with intraabdominal spill through the defect confirms injury. For this, many find that infant formula from prepackaged bottles is ideal, and it is readily available in most labor and delivery units. The circulating nurse attaches a milk-filled, 60-mL syringe to the urethral catheter and fills the bladder repeatedly to instill a total volume of 200 to 300 mL. As the bladder fills, milk is easily seen flowing from a defect in the bladder wall. If milk is not available, methylene blue is a suitable dye to mix with saline for bladder filling. Indigo carmine was another popular choice, but current nationwide shortages limit its use now. In contrast to methylene blue and indigo carmine, infant formula can be used repeatedly during a case because it does not stain surrounding tissues (Davis, 1999). Notably, small defects can be difficult to identify and repair if the tissues surrounding the defect become stained. Unrepaired defects predispose to fistula formation.

Cystotomy Repair

The first step to manage an unplanned cystotomy is evaluation of the size, location, and extent of injury. Inspection of the trigone and ureters for possible involvement is mandatory (Davis, 1999). If the trigone is involved, the surgeon should be careful not to disrupt the ureteral orifices. If the injury is close to either ureter, stents are placed to maintain ureteral patency. Rarely, a bladder laceration involves one or both ureteral orifices such that proper repair without further ureteral injury or obstruction is impossible. This will require ureteroneocystostomy.

A simple cystotomy is closed in two layers (Fig. 28-1). The first layer is a simple running closure of the mucosa with a 3-0 absorbable or delayed-absorbable suture. Suitable options are chromic gut or polyglactin 910 (Vicryl). A second layer uses 2-0 or 3-0 suture of similar material in an imbricating technique to incorporating the bladder submucosa and muscularis. The bladder is then filled with sterile milk or methylene blue-stained saline to confirm integrity of the repair. Leaking defects can be closed with individual interrupted stitches of 2-0 or 3-0 suture. An additional running suture line can be placed in the serosa, if the margins can be approximated without undue tension. Large defects or persistent leak may require revision of the closure.

After the bladder returns to its normal anatomic location, the relative position of suture lines on all organs should be inspected. Placement of the suture line in close proximity to another can increase the risk of fistula formation. To avoid this risk, an omental J-flap can be quickly fashioned and safely interposed between suture lines. That said, this step is infrequently required in obstetrics due to the typical generous distance between suture lines and the rich vascularity of genitourinary tissues in pregnancy. If elected, an omental J-flap is created by ligating the right gastroepiploic artery and mobilizing the omentum off the hepatic flexure of the transverse colon toward the midline. Leftward dissection stops to preserve blood supply to the J-flap from the right gastroepiploic artery. The flap is brought into the pelvis along the left paracolic gutter and fixed in place with one or two strategically placed stitches of 2-0 or 3-0 Vicryl or chromic gut suture (Patsner, 1997).

Following cystotomy repair, the bladder is drained with a transurethral Foley catheter for 7 to 14 days postoperatively to allow healing and minimize risk of fistula formation. Suprapubic catheterization is usually not required, and prophylactic antibiotics are not indicated. Imaging before or after Foley removal is typically unnecessary but can be considered after complex or extensive repair (Davis, 1999; Tarney, 2013). Morbidity associated with intraoperative recognition of bladder injury and proper repair is minimal.

In contrast, unrecognized injury can worsen final patient outcome. Unrepaired cystotomy can manifest as hematuria, oliguria, abdominal pain, ileus, ascites, peritonitis, sepsis, fistula, urinoma, and an elevation of the blood urea nitrogen to creatinine ratio. For diagnosis, retrograde cystography or abdominal computed tomography with cystography can be used (Tarney, 2013). Cystoscopy is also an option, but is more invasive and may require an operating room. Once identified, prompt repair is indicated in most cases. Prolonged catheter drainage may be considered in selected stable patients with small defects.

Prevention

Prevention begins with recognition of risk factors that predispose to injury and with preemptive steps. A preoperative Foley catheter decompresses the bladder, improves exposure, and may help delineate the bladder location by palpation of the bulb. Adhesion prevention includes standard surgical principles of gentle retraction, respect for tissue, meticulous surgical technique, maintenance of tissue moisture, and limiting blood loss. Hysterotomy closure may play a role, and investigators in one small study evaluated adhesions during a second cesarean delivery. They found that double-layer hysterotomy closure during a primary cesarean operation, compared with single-layer closure, reduced the odds of later developing bladder adhesions. As another factor, vertical midline infraumbilical abdominal incisions have a significantly higher risk for bladder injury than Pfannenstiel incisions. This persists even after controlling for confounding effects of number of cesareans, operator experience, and adhesions. Although these data suggest that Pfannenstiel incisions should be considered, it must be emphasized that the choice of abdominal incision is based on many maternal, fetal, and intrapartum factors and should not be based solely on cystotomy risk reduction. Specific to cystotomy prevention, data are insufficient or too conflicting to support recommendations for or against parietal peritoneal closure, bladder flap creation, type of uterine incision, or exteriorization of the uterus (Tarney, 2013).