Ureteric Injury During Caesarean Delivery

Ureteric injury during caesarean delivery is damage to the ureter by clamping, ligation, transection or kinking during repair of lateral extensions of the uterine incision, control of bleeding or hysterectomy. It is rare and most often affects the lower third of the ureter near the uterine artery. It matters because most injuries are missed at surgery and appear in days to weeks with flank pain, fever, urinary leakage and kidney damage.

• Risk factors: lateral extension of the incision, uterine artery bleeding, broad ligament haematoma, placenta accreta spectrum, caesarean hysterectomy, adhesions, emergency surgery in the second stage.
• Injury is often made while clamping and suturing blindly at the side of the uterus.
• Early diagnosis protects the kidney.

Women have flank or abdominal pain, fever, nausea and vomiting, ileus, abdominal distension (urinary ascites) and leakage of clear fluid from the wound or the vagina, usually 2 to 10 days after surgery. Ligation may cause silent hydronephrosis.

• Flank pain and a tender loin.
• Watery vaginal discharge (ureterovaginal fistula) or wound leak.
• Differential diagnosis: bladder injury, pyelonephritis, wound seroma, ileus, pelvic abscess, endometritis, vesicovaginal fistula.
• Complications: hydronephrosis, loss of kidney function, urinoma, urinary ascites, infection and sepsis, ureterovaginal fistula, ureteric stricture, repeat surgery, nephrectomy.

The diagnosis is made by imaging after clinical suspicion, or at surgery by checking the ureter.

• Intraoperative: identify the ureter before clamping in lateral bleeding; after repair, check peristalsis and flow of urine from each ureteric orifice at cystoscopy or through a cystotomy; furosemide 10 mg IV to encourage urine flow if jets are not seen.
• Postoperative: creatinine and electrolytes, urine volume and sediment; ultrasound for hydronephrosis, perinephric fluid or ascites; ascitic or drain fluid creatinine above serum creatinine.
• Contrast CT urogram with delayed images (extravasation or obstruction), or retrograde pyelography at cystoscopy.
• Dye test for fistula (methylene blue in the bladder with a tampon in the vagina).

The principle is to repair or stent at once when found, and to drain the kidney early when found late.

• Supportive: keep the woman well hydrated; monitor urine output hourly; Foley catheter to decompress the bladder; analgesia; correct electrolytes; early involvement of a urologist.
• Pharmacological: ceftriaxone 2 g IV once daily (plus metronidazole 500 mg IV 8-hourly for pelvic collections) until afebrile for 48 hours, then cefalexin 500 mg oral 6-hourly to complete 7 to 14 days; paracetamol 1 g oral 6-hourly (maximum 4 g in 24 hours); morphine 2.5 to 5 mg IV every 4 hours as needed for colic; oxybutynin 5 mg oral 8-hourly for stent discomfort; tamsulosin 400 micrograms oral at night for stent symptoms; for obstruction with sepsis give meropenem 1 g IV 8-hourly.
• Procedures: release of a ligature or kink (if recognised during surgery) with a double J stent for 4 to 6 weeks; end-to-end spatulated anastomosis over a double J stent for a partial or complete transection of the middle or upper ureter; ureteroneocystostomy (Boari flap or psoas hitch if needed) for a lower ureteric injury; percutaneous nephrostomy and an antegrade stent for a late diagnosis with hydronephrosis or infection; percutaneous drainage of a urinoma; definitive reconstruction after 6 to 12 weeks; nephrectomy only for a destroyed kidney.
• Red flags: flank pain with fever, anuria or oliguria, rising creatinine, watery vaginal discharge, urinary ascites, sepsis.
• Follow-up: creatinine and ultrasound at 1 week and 6 weeks; stent removal at 4 to 6 weeks; renal scan at 3 months to check function; review at 6 weeks; plan later births with an experienced surgeon.