Overview
- Trauma to ureter is rare because they are protected by
◦ their small size
◦ mobility
◦ adjacent vertebrae, bony pelvis, muscles - Mostly due to iatrogenic causes
- Early identification is vital, because >2 weeks later, predisposes to infection, irreversible renal damage, doubles the risk of
hypertension
Epidemiology
- 1-2.5% of all urinary tract trauma
Aetiology - Iatrogenic injury is the commonest cause and often missed intraoperatively
◦ Instances
‣ Gynaecological surgery – commonest cause
‣ Colorectal operations - APR, Sigmoid colectomy
- Laparoscopy > open
‣ Ureteroscopy
◦ Mechanisms
‣ Ligation or kinking with a suture
‣ Crush from a clamp
‣ Partial or complete transection
‣ Thermal injury
‣ Ischaemia from devascularisation
‣ During ureteroscopy - Mucosal abrasion
- Ureteral perforation
- Intussusception
- Complete avulsion (during ureteroscopy)
◦ Iatrogenic trauma risk increases due to
‣ malignancy
‣ prior surgery or radiation
‣ diverticulitis
‣ endometriosis
‣ anatomical abnormalities - External trauma
◦ Penetrating trauma
‣ Gunshot injury
◦ Blunt trauma
‣ Deceleration injury in MVA – because renal pelvis can be torn away from the ureter!
Diagnosis- Clinical
◦ Hematuria is unreliable
◦ Mode of injury
‣ External injury – suspect ureteral injury in - Blunt – if fractures of pelvic bone or lumbosacral spine
- Penetrating – if vascular or intestinal injury present
‣ Iatrogenic injury - At the time of surgery detected
◦ Direct visualisation of the damage
◦ Urine at operative field
◦ Persistent haematuria of catheter bag
◦ Laparoscopic air in the catheter bag - Later detected
◦ Flank pain
◦ Urinary incontinence
◦ Vaginal or drain urinary leakage
◦ Haematuria
◦ Fever
◦ Uraemia
◦ Urinoma - Investigations
◦ Intraoperatively
‣ Dye tests - Intra-vesical methylene blue
- Intra-ureteric methylene blue
- Intravenous indigo carmine and intraoperative cystoscopy to see presence or absence of dye influx from ureter
‣ Intra-op IVP
◦ For later presentations
‣ Gold standard – retrograde pyelography
‣ CT or IVP - Extravasation of contrast medium
- But often only hydronephrosis, mild ureteral dilatation or urinoma that is noted
‣ Dye tests - Diagnostic paracentesis with IV indigo carmine – if tap is blue → positive test
- Intravenous indigo carmine and cystoscopy to see presence or absence of dye influx from ureter
‣ Ascetic fluid for Cr, SE and BUN, if values are equal to serum
Prevention of iatrogenic trauma - Pre-op
◦ Prophylactic ureteral stent insertion in complicated cases
‣ This makes it easier for the ureter to be identified during surgery
‣ But it does not reduce the rate of injury!
‣ But it helps to identify a ureteral injury at the time of surgery (“secondary prevention”)
‣ It has some disadvantages - Complications of inserting the stent
- Cost
- Stent can alter the location of the ureter and diminish its flexibility
‣ Therefore routine prophylactic stenting is not cost effective - Intra-op
◦ Visual identification of the ureters
◦ Careful intraoperative dissection in the ureter’s proximity
‣ Upper ureter receives blood supply from medial side, so the plane of dissection should be on the lateral side
‣ Lower ureter receives blood supply from lateral side, so the plane of dissection should be on the medial side
◦ If suspicious of ureteric damage
‣ Dye tests - Intravesical methylene blue
- Intraureteral methylene blue
- Intravenous indigo carmine and intraoperative cystoscopy to see presence or absence of dye influx from ureter
‣ Intra-op IVP
Management - Depends on the time of detection, then nature, severity and location of the injury
◦ Detected at the time of surgery
Eg:
‣ Accidental ligation - de-ligation and stent placement
‣ Partial transection - primary repair immediately with a stent OR
- if patient is unstable → damage control principle → ligation and urinary diversion with a nephrostomy tube → delayed definitive repair
◦ Detected late
‣ Major ureteral injury requires ureteral reconstruction after temporary urinary diversion
‣ First treated by a nephrostomy tube → delayed definitive repair - Definitive repair principles
◦ Debridement of necrotic tissue until bleeding while protecting the adventitial plexus
◦ Ureteral ends are cut slant and spatulated for wider anastomosis
◦ Tensionless
‣ If <2cm gap – end to end anastomosis is possible
‣ If slightly bigger gap – mobilise the ureter (preserve adventitial plexus by dissecting from lateral side in upper
ureter and dissecting from medial side in lower ureter)
‣ If large gap – mobilise the bladder for a psoas hitch
◦ Watertight, mucosa-to-mucosa, full thickness anastomosis with fine absorbable 5/0 polyglactin 910 sutures, 1 mm apart,
1-2 mm from edge
◦ Over an internal stent
◦ External drain
◦ Isolation of the injury with omentum or peritoneum
◦ Urinary catheter
◦ Urinary catheter kept for 1 week, stent kept for 6 weeks - Definitive repair options
◦ General principle
‣ Proximal ureteral injuries can usually be managed with uretero-ureterostomy
‣ Distal injury often requires ureteral reimplantation because primary trauma jeopardises the blood supply to the distal ureter
◦ Upper ureter
‣ Uretero-ureterostomy
‣ Transuretero-ureterostomy - When there is extensive loss
- Distal end of the injured ureter is ligated
- Proximal end is transposed across the midline through a retroperitoneal window and anastomosed to the
contralateral ureter
‣ Uretero-calycostomy - PUJ or upper ureteral injury – ureter can be anastomosed to a lower pole calyx of the ipsilateral kidney
◦ Mid ureter
‣ Uretero-ureterostomy
‣ Transuretero-ureterostomy
‣ Ureteral reimplantation with a Boari flap - When there is a large lower ureteral injury, the large gap can be bridged with a tubularised L-shaped bladder flap
- Not suitable in the acute setting as it is time consuming
◦ Lower ureter
‣ Distal ureteral injury should be ideally managed with ureteral reimplantation as primary trauma usually jeopardises
the blood supply to the distal ureter
- Ureteral reimplantation psoas hitch
◦ This is done to bridge the gap between the bladder and the ureter so the tension on the anastomosis is less
◦ The bladder is mobilised upward – contralateral superior vesical pedicle may need to be divided to
improve the bladder mobility
◦ A non-absorbable suture between bladder and the ipsilateral psaos tendon is placed to bridge the gap
taking care not to damage the genitofemoral nerve
◦ Complete damage
‣ Ileal interposition graft
- Ileal segment is placed in the isoperistaltic orientation between the renal pelvis and the bladder
- Should not be done in a patient with impaired renal function or intestinal disease
- Follow up to see if patient develops hyperchloraemic metabolic acidosis
◦ Because in bowel Na+ and HCO3- are secreted in exchange of H+ and Cl-
◦ Now that it is incorporated in to the urinary tract, in addition to H+ and Cl-, ammonia (NH4+) is also
absorbed when urine is in contact with bowel wall.
◦ This leads to chronic acid load and high chloride in the blood!
‣ Autotransplantation
- When multiple ureteral repairs fail, kidney can be relocated in the pelvis, renal vessels anastomosed to the iliac vessels and ureteral reimplantation done.
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