Surgical repair of an iatrogenic ureteral injury

INTRODUCTION — Intraoperative iatrogenic ureteral injuries, if recognized during the operation, should be repaired in that setting [1]. Ureteral injuries identified in the postoperative period require a delayed operative repair.

Ureteral injuries can occur during open or laparoscopic intra-abdominal, vaginal, and endourological procedures. In a retrospective review of 165 patients with iatrogenic ureteral injuries over a 20 year span, endourologic procedures were responsible for most iatrogenic injuries [2]. Urologic, gynecologic, and general surgical procedures were responsible for 42, 34, and 24 percent of injuries, respectively.

Injury to the ureter is the most common complication of pelvic surgery, ranging from less than 1 to 10 percent of procedures, depending on the complexity of the procedure [2-6]. Prevention is ideal, and early recognition is the next best approach. Nevertheless, despite preventive measures (eg, radiographic imaging, ureteral stents) to minimize injury to the ureter in high-risk clinical settings (eg, previous pelvic surgery, one functioning kidney), injuries still occur, and a high level of intraoperative and postoperative vigilance is indicated [7].

The surgical management of iatrogenic ureteral injuries, whether identified early or late, is discussed here. The incidence, prevention, recognition, and evaluation of ureteral injuries following gynecologic and colorectal procedures are reviewed elsewhere. (See "Urinary tract injury in gynecologic surgery: Identification and management" and "Urinary tract injury in gynecologic surgery: Epidemiology and prevention" and "Management of intra-abdominal, pelvic, and genitourinary complications of colorectal surgery", section on 'Ureteral injury'.)

GENERAL APPROACH — Most ureteral injuries are not identified intraoperatively but rather in the postoperative period [3-5,8]. The general principles of recognizing an iatrogenic injury to the ureter are the same, regardless of the indications of the operative procedure.

An intraoperative consultation with a skilled urologist is necessary if the operating surgeon is inexperienced with a primary or advanced repair and stenting of a ureter. Prior to initiating the repair, the surgeon should review the preoperative imaging of the urinary tract (if performed) and extensiveness of the injury, including contralateral ureteral and bladder injury. Indigo carmine or methylene blue is administered intravenously to aid in evaluating the integrity of the ureters. Alternatively, the dyes are instilled via a urethral catheter to help identify or confirm bladder injuries. The surgeon should determine if both kidneys are functioning.

If a patient has received antibiotic prophylaxis for the procedure, additional antibiotics are not administered for a ureteral injury. Antimicrobial prophylaxis for genitourinary surgery, gynecologic and obstetrical surgery, and colon and rectal surgery is provided in the accompanying tables (table 1). If a patient has not received prophylactic antibiotics, we administer antimicrobial agents (cephalosporins, gentamicin, or fluoroquinolones) to cover enteric gram-negative bacilli that comprise most urinary tract pathogens.

Intraoperative and postoperative recognition and evaluation of ureteral injury are reviewed separately. (See "Urinary tract injury in gynecologic surgery: Identification and management", section on 'Postoperative evaluation and diagnosis'.)

MANAGEMENT OF CONTUSION — Minor contusions can be managed with insertion of a ureteral stent [9]. If the contusion is substantial, or if the blood supply is in question, the injured section of the ureter should be debrided to healthy tissue and a ureteroureterostomy performed. (See 'Ureteroureterostomy' below.)

MANAGEMENT OF A LIGATION — If the ureter is inadvertently ligated, the suture should be removed and the ureter observed for viability. If compromise is observed, the injured ureter should be resected and a ureteroureterostomy performed [10]. (See 'Ureteroureterostomy' below.)

SURGICAL REPAIR

Overview — If the injury is recognized early during an open or laparoscopic procedure, it should be repaired in the same setting. If the injury is recognized early, placement of a ureteral stent is attempted. If not feasible, a primary repair is attempted. Advances in endourologic technique and equipment may provide a minimally invasive approach to postoperative iatrogenic injuries. Endoscopic realignment utilizing one or more stents for complete ureteral transections has been used for immediate postoperative and delayed injury cases [11,12].

Primary repair (eg, ureteroureterostomy, ureteroneocystostomy) is the preferred approach for ureteral injuries recognized intraoperatively. A primary ureteroureterostomy is the optimal technique when the anastomosis can be performed without tension. The ureteral anastomosis following any type of primary repair is typically stented.

When more extensive damage is present that would preclude a primary anastomosis, an advanced surgical repair, such as a flap procedure, autotransplantation, or nephrectomy, is performed. When the initial approach was laparoscopic or for a delayed repair, a laparoscopic repair can be performed [13]. (See 'Role of minimally invasive repair' below.)

The approach for patients with a delayed recognition of a ureteral injury is controversial [10]. Some advocate for stent placement as the first line of therapy while others perform a primary repair as soon as possible. If the injury is recognized late and there are complications (eg, abscess, urinary infection, urinary fistula) that would interfere with ureteral healing, proximal urinary drainage by a percutaneous nephrostomy is performed. (See 'Nephrostomy' below.)

The following sections describe the repair of an injured ureter based on the location of the injury (eg, lower, middle, and upper ureter) (figure 1 and figure 2).

Lower ureter — Approximately 90 percent of the trauma to the ureter occurs in the lower portion, which extends from the inferior border of the sacroiliac joint to the ureterovesical junction (figure 3 and figure 4) [3].

Transection injuries are repaired by a primary ureteroureterostomy, ureteral implant, or psoas hitch, depending on the severity of the injury and approximation to the ureterovesical junction (figure 5).

Ureteroureterostomy — If the ureteral injury is approximately 3 to 4 cm proximal to the ureterovesical junction, a primary ureteral anastomosis is performed.

The following general principles are applied when performing an ureteroureterostomy [9,10]:

●Mobilize the ureter to obtain adequate length for repair without devascularization.

●The edges of both the proximal and distal ureteral segments are resected to ensure that viable tissue is being anastomosed.

●Both ends of the ureter are spatulated and the anastomosis is performed using interrupted, absorbable sutures (figure 6).

●The anastomosis must be tension free.

●A stent is routinely utilized (picture 1 and image 1). It can be inserted by immediate cystoscopy or by a cystotomy.

●The site of the anastomosis is drained.

●The retroperitoneum is closed over the anastomosis. If not technically feasible, the anastomosis is isolated by using an omental flap.

Ureteroneocystostomy — When the ureteral injury is within the distal 2 cm from the ureterovesical junction, a primary ureteral repair is difficult. In these settings, a ureteroneocystostomy (ureteral reimplant) is usually preferred. There are several techniques described, such as the Leadbetter-Politano and extravesical approaches [14-16].

●Leadbetter-Politano is an intravesical technique that involves creating a submucosal tunnel to create a "flap valve" and prevent reflux [17]. The ureter enters the bladder superiorly for a distance of 2 to 3 cm, is tunneled under the mucosa, and is anastomosed directly to the bladder mucosa with interrupted absorbable sutures.

●Extravesical approaches, such as the Lich-Gregoire, involve incision of the detrusor muscle to create a trough for the ureter, followed by mucosal anastomosis and subsequent closure of the trough to create an antirefluxing mechanism [18].

In our practice, we prefer the nonrefluxing Leadbetter-Politano technique, in which the ureter is reattached to the bladder in a medial and superior position to the original insertion site, particularly for women of childbearing age. Whether to stent the reimplanted ureter is determined by the surgeon. We use a stent if the ureter has been extensively mobilized prior to the reimplantation. However, all ureteral reimplantations should be drained.

Psoas hitch ureteral reimplantation — The psoas hitch ureteral reimplantation is the best approach when a primary ureteroureterostomy or ureteroneocystostomy cannot be performed without tension [19-21].

The following general principles are applied when performing a psoas hitch procedure (figure 7) [22-24]:

●Mobilization of the bladder on both the ipsilateral and contralateral sides of the injury facilitates a tension-free anastomosis.

●The cystotomy is performed on the anterior wall of the bladder, away from the dome. This enables mobilization of the bladder, as well as placement of the anchoring stitches in the psoas tendon.

●The bladder is anchored to the psoas tendon with nonabsorbable stitches. Inserting the surgeon's fingers into the bladder dome facilitates placement.

●When anchoring the bladder to the psoas tendon, avoid injury or entrapment of the genitofemoral nerve within the sutures.

●The ureter is then reimplanted. We prefer to use the Leadbetter-Politano technique and, in these cases, leave an indwelling ureteral stent.

●The cystostomy is closed with an absorbable suture.

●A urethral catheter is left in place; a suprapubic tube is usually not necessary unless the surgeon anticipates bloody urine that could result in an obstructed urethral catheter.

●The reimplantation site is drained.

Middle ureter — Approximately 7 percent of all ureteral injuries occur in the middle third of the ureter, which extends from the upper border to the lower border of the sacroiliac joint [3].

The optimal repair for a midureteral transection is a ureteroureterostomy (see 'Ureteroureterostomy' above). For more extensive injuries, or for when an anastomosis cannot be performed without tension, a transureteroureterostomy or a Boari flap is used. A transureteroureterostomy cannot be performed in a patient with a history of renal stones or a nonfunctioning contralateral kidney.

Boari flap — The Boari flap is the optimal, but complex, approach for repair of an extensive midureteral injury (figure 8) [25-29].

The following general principles are applied when performing a Boari flap [3]:

●Similar to the technique for a psoas hitch, the bladder must be thoroughly mobilized.

●Before the flap is created, the bladder should be distended with saline and the flap carefully planned with a sterile marker.

●A rectangular flap is created on the anterior surface of the bladder. The most critical maneuver is to preserve blood supply to the flap. Hence, the base must be at least 4 cm wide (wider for longer flaps), and the superior vesical artery must be preserved.

●The flap is sutured to the psoas tendon with nonabsorbable sutures. (See 'Psoas hitch ureteral reimplantation' above.)

●The ureter is tunneled through the proximal portion of the flap, and a neo-orifice is created.

●The bladder flap is tubularized with running absorbable sutures.

●The distal ureter is anastomosed to the flap using a running absorbable suture.

●The anastomosis is stented.

●The anastomotic site is drained.

●An indwelling urethral catheter drains the bladder.

●A suprapubic tube is used if the surgeon anticipates a large amount of bloody urine.

Transureteroureterostomy — A transureteroureterostomy, which is rarely used, utilizes an anastomosis between ureters, where the injured ureter crosses the midline to meet the contralateral ureter (figure 9) [9,20,23,30-32].

The following general principles are applied when performing a transureteroureterostomy:

●Both the donor and recipient ureters are mobilized to prepare for a tension-free anastomosis.

●The recipient ureter should never be angulated to reach the donor ureter.

●The donor ureter is spatulated, and then stay sutures are placed in the recipient ureter.

●The ureteroureterostomy is performed between the stay sutures using running 4-0 chromic suture with the knot on the outside on the posterior wall. Interrupted sutures are used on the anterior wall.

●Typically, the anastomosis is unstented.

●The anastomotic site is always drained.

Upper ureter — Injuries to the upper ureter, which extends from the ureteropelvic junction to the upper border of the sacroiliac joint, occur in only 2 percent of all ureteral injuries [3]. The optimal procedure for repair of an upper ureteral injury is a ureteroureterostomy, if sufficient length can be mobilized for a primary repair without tension. This can be facilitated by mobilization of the kidney with fixation to the psoas tendon (nephropexy) to provide for a tension-free anastomosis. Mobilization of the left kidney can provide up to 4 cm of length, but mobilization of the right kidney does not add much length to the right ureter, as the right kidney is limited by a short right renal vein. The general principles are described in a preceding section. (See 'Ureteroureterostomy' above.)

When sufficient length cannot be mobilized for ureteroureterostomy, the options include an autotransplantation, ileal or appendiceal interposition graft, or a nephrectomy. In most settings of an upper ureteral injury, the Boari flap is technically unfeasible.

Autotransplantation — Autotransplantation of the kidney, which involves moving the injured ureter and ipsilateral kidney to an ectopic site (eg, iliac fossa), is a complex procedure and should not be undertaken if other options exist (figure 10) [27,33,34]. It is usually considered when the contralateral kidney is absent or poorly functioning. The kidney is harvested with maximal vessel length for anastomoses to the iliac artery and vein. The upper ureter or renal pelvis can be directly anastomosed to the bladder.

Ileal or appendiceal interposition graft — This approach is rarely considered as a first-line procedure [35,36]. The use of ileal or appendiceal interposition graft for extensive upper ureteral injuries has been described [3,20,27,37-39].

As with autotransplantation, bowel interposition should be considered only when simpler alternatives are not practical. We prefer to use the ileum if the patient has had a preoperative bowel preparation (although not an absolute prerequisite) and in emergency settings. The techniques used for creation of an ileal ureter are similar to those used in an ileal conduit. The proximal and distal ureteral segments are fully mobilized, and the ureteral-ileal anastomosis is performed with absorbable sutures. No stents are utilized, and the anastomosis site is drained.

Nephrostomy — A nephrostomy can be inserted if the upper ureteral injury is not amenable to a primary repair for early and/or delayed recognition of injury. It can also be used if the primary repair at any level is under tension. In the setting of an abscess or fistula and delayed recognition, this is an acceptable option for drainage until a primary repair can be performed.

Nephrectomy — A nephrectomy should only be used in rare settings. When a normal contralateral kidney is present, a simple nephrectomy can be considered as an expeditious option to an extensive upper ureteral injury or when ureteral injury occurs during procedures using prosthetic grafts [9,23,40]. Nephrectomy eliminates the risk of ureteral leak from an anastomosis and, as an independent procedure, is associated with low mortality [41].

ROLE OF MINIMALLY INVASIVE REPAIR — Laparoscopic ureteral repair is technically feasible and is an alternative to open repair for delayed diagnosis of a ureteral injury [42,43]. When performed laparoscopically, ureteroureterostomy and ureteroneocystostomy anastomoses are technically easier to perform than an implantation; a Boari flap is challenging but feasible [29,44]. Robotic-assisted laparoscopy for ureteral reimplantation and repair is another minimally invasive approach that can be performed efficaciously when performed by skilled surgeons [45,46].

Most cases and series involve ureteroneocystostomy with psoas hitch ureteral implantation either by an extravesical [47] or intravesical [48] or extravesical cystoscopy-assisted [49] techniques. The latter two approaches create a submucosal tunnel and allow for nonreflux reimplantation of the ureter. There is limited experience with robotic-assisted approaches for ureteroneocystostomy [50,51].

POSTOPERATIVE CARE AND FOLLOW-UP — The management specific for the ureteral injury includes:

●Remove the suprapubic tube, if used, on postoperative day 2 or 3, providing the urine is clear.

●Obtain a cystogram at day 7.

●Remove the indwelling urethral catheter when no leak is observed on the cystogram, typically seven days postoperatively.

●Obtain computed tomography (CT) urogram two to three weeks after surgery to confirm no anastomotic leak. Internal stents are removed only after no leak is demonstrated.

●We do not use prophylactic antibiotics, even with prolonged use of an indwelling catheter. (See "Catheter-associated urinary tract infection in adults", section on 'Prevention'.)

POSTOPERATIVE COMPLICATIONS — Most patients with immediate recognition of the injury have few complications. Urinary leakage occurs in approximately 10 to 24 percent of ureteroureterostomy repairs for injury, including early and delayed recognition [9]. Most urinary leaks that occur in the early postoperative period can be managed successfully with continued drainage. If an unstented ureter is leaking, either a stent or nephrostomy tube can usually successfully manage the problem.

Less common acute complications include abscess and fistula formation. Abscesses should be drained, either percutaneously or by an open procedure, depending upon technical expertise and amenability of the abscess to percutaneous drainage.

LONG-TERM OUTCOMES — Long-term outcome data are limited to small series and case reports [24,35,36,42,43,52-54]. Long-term results are excellent if the diagnosis and repair is performed at the time of injury [9,10]. A delay in diagnosis worsens the prognosis because of infection, hydronephrosis, abscess, and fistula formation.

Ureteral strictures, which occur in 10 percent of ureteroureterostomy repairs, typically are a late complication of ureteral injury [9]. In most cases, they can be managed endoscopically with balloon dilation. If endoscopic management fails, then open repair may be necessary.

Ureteral reflux is expected in patients in whom an antirefluxing type of reimplantation is not performed. In the adult, reflux generally does not lead to long-term problems with infection or pyelonephritis, and renal deterioration is uncommon. Obstruction at the site of reimplantation is uncommon (<5 percent) and may necessitate dilation or open repair with redo reimplantation.

Fistula formation is very uncommon (<1 percent of repairs), especially if the repair is stented and drained. Ureteric fistulas are typically caused by distal obstruction.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Genitourinary tract trauma in adults".)

SUMMARY AND RECOMMENDATIONS

●Setting – Intraoperative iatrogenic ureteral injuries, if recognized during the operation, should be repaired in that setting.

●Optimal approach to surgical repair – For lower, middle, and upper ureteral injuries, we perform a ureteroureterostomy as the optimal approach if it can be performed without anastomotic tension. (See 'Ureteroureterostomy' above.)

●Lower ureteral injuries – For lower ureteral injuries that cannot be reapproximated with a tension-free anastomosis, and when the injury is within the distal 2 cm from the ureterovesical junction, we perform a ureteroneocystostomy. (See 'Ureteroneocystostomy' above.)

For lower ureteral injuries that cannot be repaired by a ureteroureterostomy or ureteroneocystostomy, we perform a psoas hitch implantation repair. (See 'Psoas hitch ureteral reimplantation' above.)

●Middle ureteral injuries – For middle ureteral injuries, a ureteroureterostomy without tension is the optimal repair. A transureteroureterostomy or a Boari flap is performed for extensively injured middle ureters (see 'Middle ureter' above). A transureteroureterostomy cannot be performed in a patient with a history of renal stones or a nonfunctioning contralateral kidney.

●Upper ureteral injuries – For upper ureteral injuries, the optimal repair is a ureteroureterostomy. However, in situations where there is insufficient proximal ureter for a tension-free anastomosis, options include an autotransplant, bowel interposition graft, or a nephrectomy. (See 'Upper ureter' above.)

ACKNOWLEDGMENTS — The UpToDate editorial staff acknowledges Kevin R Loughlin, MD, MBA, and Colleen Feltmate, MD, who contributed to earlier versions of this topic review.