Management of Iatrogenic Ureteral Injury - Surgical Interventions and Their Complications

Introduction:

A pair of tubes that enable the urine to move from the kidneys to the bladder are called ureters. The bladder is a structure of elastic fibers and muscle where the urine accumulates and is emptied during micturition (urination). The ureter is delicate, roughly 30 cm long, and wide as a pencil. Lower urinary tract injury during gynecologic surgical intervention is fairly odd. Bladder damage is the most common urologic injury unintentionally caused by a surgeon. These injuries are identified and rectified instantly, with the possibility of minor complications. However, ureteral injuries commonly are not determined directly or mismanaged ureteral injury and can significantly be life-threatening or result in urinoma (mass of encapsulated extravasated urine collection), abscess (pus formation), ureteral stricture (narrowing of the ureter), even permanent kidney damage or kidney removal, or even death.

Even though iatrogenic ureteral damage is rare, it frequently needs to be repaired by a urologist. The ureter is susceptible to damage during gynecologic, general surgery, and urologic operations, particularly in the pelvis. When postoperative fever, flank discomfort, leukocytosis, and peritonitis are present, doctors should suspect ureteral damage. The location of the ureteral damage determines surgical management. The most often used treatment approach for distal ureteral injuries is ureteroneocystostomy, either with or without a vesico-psoas hitch (a surgical procedure done to manage lower ureteral injuries).

What Are the Causes of Iatrogenic Ureteral Injury?

• Ureteral injuries are considered the most common complication of any open, laparoscopic, or endoscopic pelvic procedure. These injuries are often subtle and mainly caused by gynecologic, urologic, general, hysterectomies, vascular, and colorectal surgery. Whereas with the recent advances in the field of surgery, the introduction of technology-related tools for ureteral complications has declined over the years because of modifications in surgical technique.

• Suture ligation of the ureter.

• Sharp incision.

• Transection (a transverse division in the ureter or cut).

• Avulsion.

• Devascularization.

• Heat energies from the electronic surgical tools.

• Ureteral trauma is infrequent and is less than 1 % of direct and penetrating genitourinary trauma, common with gunshot wounds, with the proximal ureter being most commonly affected.

What Are the Types of Iatrogenic Ureteral Injury?

1) Based on location, ureteral injuries can be categorized as:

• Ureteropelvic junction (UPJ).

• Abdominal ureter from the ureteropelvic junction (UPJ) to iliac vessels.

• Pelvic ureter from inferior to iliac vessels.

2) Based on the time of onset, ureteral injuries can be classified as:

• Immediate Diagnosis: Where the injuries are recognized or diagnosed shortly after damage.

• Delayed Diagnosis: Where the injuries are recognized or diagnosed long or late after surgery.

The American Association for the Surgery of Trauma (AAST) categorizes ureteral damages as follows:

Grade I: Hematoma or contusion without devascularization.

Grade II: Laceration with less than 50 percent transverse cut in the ureter.

Grade III: Laceration with 50 percent or greater transverse cut in the ureter

Grade IV: Laceration with complete transverse cut in the ureter with less than 2 cm (centimeter) of devascularization.

Grade V: Laceration with avulsion greater than 2 cm of devascularization.

How Is Iatrogenic Ureteral Injury Evaluated?

The fluid can be tested for spot creatinine if a surgical drain is present. Spot creatinine will usually be 25 to 450 mg/dL when the fluid is urine, but it will be equivalent to serum creatinine when it is not the urine, which helps to evaluate kidney function. Elevated creatinine indicates suspicion of some disruption to the collecting system, preventing urine drainage.

Imaging studies are the most crucial diagnostic tools for evaluating ureteral injury.

• Retrograde Pyelogram (RPG): It is the most precise imaging examination to assess the area and size of the ureteral injury.

• Antegrade Pyelogram: It can be used if the patient has an antegrade entrance.

• Computerized Tomography (CT) Urogram: Evaluating the urinary tract with IV contrast and identifying the ureteral injury.

What Are the Surgical Interventions for Iatrogenic Ureteral Injury?

Surgical principles are essential for successful ureteral repair.

• To debride all devitalized tissue.

• Sufficient ureteral mobilization is required to permit tension-free anastomosis.

• Preserve the ureter adventitia and vasculature to secure a good ureteral blood supply.

• Spatulation of the ureteral ends and a tension-free but fluid-tight mucosa-to-mucosa anastomosis over a ureteral stent with the help of an absorbable suture.

The choice of repair depends on the classification of the ureteral injury site and the identification timing.

• Injury to the upper or middle portion of the ureter: Ureteroureterostomy (UU) or transureteroureterostomy (TUU).

• Injury is to the lower ureter: Ureteral reimplantation, also called ureteroneocystostomy, psoas hitch, or board flap.

The following surgical interventions are undertaken:

• Ureteroureterostomy (UU): It is the primary end-to-end anastomosis of the segment of the same ureter of the injured ureter with excision of the injured or scarred tissue. This repair is most suitable for small ureteral defects and is chosen for the pediatric population mostly to repair the abdominal ureter, where tension-free anastomosis can be assembled.

• Transureteroureterostomy (TUU): Urinary reconstruction technique that joins one ureter to the other across the midline and anastomosing the damaged ureter to the contralateral ureter in an end-to-end technique. This approach offers patients with distal ureteral obstruction.

• Ureteral Reimplantation (Ureteroneocystostomy): Implicates reimplanting the ureter directly to the bladder using a psoas hitch or Boari flap is required to assist in reimplantation.

• Ureteropyelostomy: This is a surgical procedure where the ureter is anastomosed to the renal pelvis. Ureteral Stents are used in case ureteral perforation occurs during endoscopy.

• Ureterocalicostomy: This procedure is done where the inferior pole of the kidney is amputated to reveal the infundibulum area within the kidney. Then, the ureter is anastomosed to the infundibulum.

What Are the Complications Related to Repair Surgery of Ureter Injury?

• Urinoma and ureterovaginal fistula.

• The most common complication is urine leakage from ureteral damage, causing urinoma, eventually leading to infection or abscess. In addition, extravasated urine can irritate adjacent organs and tissues like the intestines and peritoneum, leading to pain.

• Ureter stricture: In the ureter stricture, a constriction within the ureter pipe-like structure results in no urine drainage. Thus the obstruction causes loss of renal function and, ultimately, renal failure.

Conclusion:

Endourological procedures are the most common cause of iatrogenic ureteral injuries. However, when recognized as an injury and treated properly as soon as possible and with proper management, such injuries rarely cause loss of renal function. In contrast to the surgical approach for any condition, always check for symptoms that the body communicates and address the sign with the proper follow-up to avoid future complications.