432 CHAPTER 10 Trauma to the urinary tract
Ureteral injuries: mechanisms and diagnosis
Types, causes, and mechanisms
•External: nearly always due to penetrating trauma (knife or gunshot wounds); only rarely due to blunt trauma
•Iatrogenic: during pelvic or abdominal surgery (e.g., hysterectomy, colectomy, appendectomy, AAA repair; repeated or traumatic ureteroscopy). The ureter may be divided, ligated, or angulated by a suture or damaged by diathermy.
External injury: diagnosis
Suspicion for possible ureteral injury is based on wound location or the above clinical scenarios. Hematuria may be absent in 30% of cases.
Imaging studies
In stable patients, contrasted CT with delayed cuts (10–20 minutes) is superior to IVP for clearly determining the presence of a ureteric injury (Fig. 10.6). If doubt remains regarding the integrity of the ureters, retrograde pyelography should be done.
Iatrogenic injury: diagnosis
The injury may be suspected at the time of surgery, but injury may not become apparent until some days or weeks postoperatively.
Intraoperative diagnosis
Direct inspection of the ureter
IVP is notoriously inaccurate for detecting ureteral injuries. Direct intraoperative inspection of the ureter is the best way to detect injury of the ureter. IV injection of methylene blue or indigo carmine may reveal a laceration. Direct injection into the ureter, either retrograde or antegrade, may also reveal extravasation from a laceration.
Ureteral contusion
Discoloration of the ureter observed during laparotomy suggests ischemic injury related to a blast effect after an abdominal gunshot wound. This may lead to a delayed slough and leak if not repaired and/or stented primarily.
Postoperative diagnosis
The diagnosis is usually apparent in the first few days following surgery (see Box 10.3), but it may be delayed by weeks, months, or years (presentation is flank pain; post-hysterectomy incontinence—continuous leak of urine suggests a ureterovaginal fistula).
Investigation
Ultrasonography may demonstrate hydronephrosis, but hydronephrosis may be absent when urine is leaking from a transected ureter into the retroperitoneum or peritoneal cavity.
IVP may show an obstructed ureter or possibly a contrast leak from the site of injury, but CT is more accurate and is thus preferred. Retrograde pyelogram is an accurate method of delineating the site of injury, but is best used in conjunction with attempted stent placement.
URETERAL INJURIES: MECHANISMS AND DIAGNOSIS 433
Figure 10.6 CT of patient with right ureteral injury after stab wound.
Box 10.3 Symptoms and signs of ureteral injury
These may include the following:
•Ileus (due to urine within the peritoneal cavity)
•Prolonged postoperative fever or overt urinary sepsis
•Drainage of fluid from drains, abdominal wound, or vagina. Send aliquot for creatinine estimation. Creatinine level higher than that of serum = urine (creatinine level will be at least 300 µmol/L
[4.0 mg/dL]).
•Flank pain if the ureter has been ligated
•Abdominal mass, representing a urinoma
•Vague abdominal pain
•The pathology report on the organ that has been removed may note presence of segment of ureter.
434 CHAPTER 10 Trauma to the urinary tract
Ureteral injuries: management
When to repair the ureteral injury
In general, the best time to repair the ureter is as soon as the injury has been diagnosed (if intraoperatively), or if the diagnosis is made within the first week after injury. If the diagnosis is made between days 7 and 14 after ureteric injury, caution is advised, since edema and inflammation at the site of repair often occur.
Percutaneous nephrostomy should be placed, the infection drained percutaneously, intravenous antibiotics given, and ureteric repair delayed until the patient is stable and afebrile.
Delay definitive ureteral repair when
•The patient is unable to tolerate a prolonged procedure under general anesthesia—(consider damage control: divert urine by placing a 90 cm single J stent through the defect into the kidney, suture into place, and bring out to abdominal wall in anticipation of later repair).
•There is evidence of active infection at the site of proposed ureteral repair (infected urinoma).
•Diagnosis is made more than 14 days after injury.
Definitive treatment of ureteral injuries
The options depend on the following:
•Whether the injury is recognized immediately
•The nature and level of injury
•Other associated problems
The options are as follows (see also Box 10.4):
•JJ stenting for 3–6 weeks (e.g., ligature injury from absorbable suture—may cut suture if recognized intraoperatively). Stent
placement is also indicated for cases of ureterovaginal fistula.
• Primary closure of partial transection of the ureter and stent placement
•Direct spatulated anastomosis (primary ureteroureterostomy)—if the defect between the ends of the ureter is short (<2 cm) and a tensionfree anastomosis is possible (usually performed for upper ureteral injuries in a setting of immediate laparotomy after a gunshot wound)
•Reimplantation of the ureter into the bladder (ureteroneocystostomy) either directly (for short traumatic lower ureteral injuries) or with psoas hitch and/or a Boari bladder flap (for longer injuries or those associated with extensive fibrosis; Figs. 10.7 and 10.8) may reach up to L4–5 level.
•Transureteroureterostomy (Fig. 10.9) is only used in a setting of advanced pelvic fibrosis, and is contraindicated if there is history of stone disease or pelvic malignancy (best used in delayed setting).
•Replacement of the ureter with ileum is used when the segment of damaged ureter is very long. It is used rarely, only if the urinary tract cannot be used (e.g., Boari bladder flap), in a delayed setting.
•Autotransplantation of the kidney into the pelvis is used when the segment of damaged ureter is very long.
•Permanent cutaneous ureterostomy is used when the patient’s life expectancy is limited.
URETERAL INJURIES: MANAGEMENT 435
Nephrectomy is traditionally advocated for ureteral injury during vascular graft procedures (e.g., aortobifemoral graft for AAA), but the current trend is toward repair and renal preservation, reserving nephrectomy only when urine leak develops postoperatively.1
Nephrectomy is best used when ureteral injury is high and extensive, and the patient is not a candidate for ileal ureter or Boari flap reconstruction (e.g., hostile abdomen, older or debilitated patient).
Box 10.4 General principles of ureteric repair
•Optical magnification via 2.5x loupes is suggested.
•The ends of the ureter should be mobilized and débrided judiciously.
•The anastomosis must be tension free.
•For complete transection, the ends of the ureter should be spatulated, to allow a wide anastomosis to be done.
•A stent should be placed across the repair.
•Mucosa-to-mucosa anastomosis should be done, to achieve a watertight closure.
•Use fine sutures (4/0 or 5–0 absorbable suture material on RB-1 needle).
•A drain should be placed near the site of anastomosis.
•Repair should be covered with the peritoneal flap and/or retroperitoneal fat to exclude the site from the abdominal cavity.
1 McAninch JW (2002). In Walsh PC, Retik AB, Vaughan ED, Wein AJ (Eds.) Campbell’s Urology, 8th edition. Philadelphia: W.B. Saunders, pp. 3703–3714.
436 CHAPTER 10 Trauma to the urinary tract
Figure 10.7 A psoas hitch. This figure was published in Walsh PC, et al. Campbell’s Urology, 8th edition, pp. 3703–3714. Copyright Elsevier 2002.
URETERAL INJURIES: MANAGEMENT 437
Damaged ureter
Incision for flap
A
B
C
Figure 10.8 A Boari flap. This figure was published in Walsh PC, et al. Campbell’s Urology, 8th edition, p. 3703–3714. Copyright Elsevier 2002.
438 CHAPTER 10 Trauma to the urinary tract
Figure 10.9 Transureteroureterostomy. This figure was published in Walsh PC, et al. Campbell’s Urology, 8th edition, p. 3703–3714. Copyright Elsevier 2002.
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