Editing Upper Urinary Tract Trauma (section)

== Ureteral Trauma ==

=== Epidemiology ===

* Rare, accounting for 1% of urologic injuries.

=== <span style="color:#ff0000">Pathogenesis ===

* '''Acute ureteral injury results from (3):''' 
*# '''Iatrogenic injury''' (open surgery, laparoscopy, and endoscopic procedures)
*# '''External violence''' from high-speed blunt mechanisms
*#*The presence of massive force injuries in the patient with blunt trauma should always increase the level of suspicion for ureteral injury
*# '''Penetrating stab and gunshot wounds'''

* '''<span style="color:#ff0000">Iatrogenic injury''' 
** '''<span style="color:#ff0000">Procedures most commonly associated with iatrogenic ureteral injuries:''' 
*** '''<span style="color:#ff0000">Hysterectomy (54%)'''
*** Colorectal surgery (14%)
*** Ovarian tumor removal (8%)
*** Transabdominal urethropexy (8%)
*** Abdominal vascular surgery
** '''Compared to open surgery, ureteral injuries during laparoscopic surgery are less likely to be recognized immediately.''' 
*** '''During laparoscopy/robotic surgery, a high index of suspicion for ureteral injury is required.'''
*** In open surgery, 1/3 of ureteral injuries are recognized immediately.
*** '''<span style="color:#ff0000">Intraoperative assessment of ureters'''  
**** Some have advocated maneuvers to check the patency of the ureter after all surgeries in which ureteric injury is commonly reported (e.g., hysterectomy).
**** '''<span style="color:#ff0000">Options (3):'''  
****# '''<span style="color:#ff0000">Direct inspection''' 
****#* '''<span style="color:#ff0000">Purposefully opening the retroperitoneum''' before or after hysterectomy has been advocated to avoid ureteral injury or at least allow intraoperative detection.
****# '''<span style="color:#ff0000">Retrograde pyelography'''
****#'''<span style="color:#ff0000">Injection of 5-10 mL of IV methylene blue or indigo carmine dye followed by cystoscopy'''  
****#* '''<span style="color:#ff0000">Poor predictor of injury'''
****#* '''<span style="color:#ff0000">Goal of cystoscopy is to document the absence of hematuria and the presence of bilateral ureteral jets'''
****#* '''IV methylene blue and indigo carmine''' are generally considered to be benign drugs, but their use has resulted in patient deaths and fetal deaths when used in pregnant women.  
****#** '''Intravenous methylene blue'''
****#***Standard 1% concentration used in clinical settings
****#****1% = 1 g in 100 ml ( =1000mg in 100ml = 10mg in 1 ml)
****#***'''Safe if used within therapeutic doses of <2mg/kg[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7693951]'''
****#**Adverse events
****#***Intravenous
****#****Burning sensation
****#****Rash
****#****Abscess
****#****Necrosis
****#****Ulceration
****#***Subcutaneous and intradermal
****#****Adverse skin reactions
****#****Superficial ulcers
****#****Abscess
****#**'''Contraindications for IV methylene blue (3):[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7693951]''' 
****#**#'''Pregnancy (potentially teratogenic)'''
****#**#'''Use of selective''' (e.g., paroxetine, sertraline, fluoxetine, fluvoxamine, citalopram) or nonselective (e.g., imipramine) '''serotonin (SSRI) and serotonin-norepinephrine (SNRI) reuptake inhibitors'''
****#**#* Methylene blue is a potent monoamine oxidase inhibitor and has caused deaths from serotonin toxicity in patients taking medications that increase serotonin levels
****#**# '''Glucose-6-phosphate dehydrogenase deficiency'''  
****#**#* Causes methemoglobinemia and hemolysis
****#**#'''Heinz body anemia'''
****#**#Renal insufficiency
****#**#*
****#** '''Contraindications for IV indigo carmine:'''  
****#**# '''Pregnancy'''
****#*** IV indigo carmine has been implicated in rare but serious cases of bronchospasm, bradycardia, hypertension, hypotension (most common), and anaphylactoid reactions.
***** '''Not effective methods'''  
****** '''Intraoperative single-shot IVP'''
****** '''Intraoperative hydration or diuretic administration'''  
******* Has been suggested to enhance ureteral visualization and potentially decrease the risk for injury
******* No data to support this method
****** '''Digital palpation of the ureter''' 
******* '''Appears to be ineffective'''
****** '''Grasping the ureter with forceps to evoke ureteral peristalsis'''  
******* '''Highly ineffective;''' should never be relied upon.
*'''<span style="color:#ff0000">Endoscopic injury'''
**Ureteroscopy should be performed alongside or over a wire placed up into the renal pelvis
**'''Factors associated with higher complication rates during ureteroscopy (4):'''
**# '''Longer surgery times'''
**# '''Treatment of renal calculi'''
**# '''Surgeon inexperience'''
**# '''Previous irradiation'''
** '''<span style="color:#ff0000">Persistence of stone basket attempts after recognition of a ureteral tear is a cause of ureteral injury during ureteroscopy.''' 
*** '''<span style="color:#ff0000">When ureteral perforation is identified, stop the procedure and place a ureteral stent'''

* '''<span style="color:#ff0000">Intraoperative ureteral manipulation''' 
** '''<span style="color:#ff0000">Common after aortoiliac and aortofemoral bypass surgery (12-20%) and may result in hydronephrosis''' 
*** '''<span style="color:#ff0000">Management: course is benign in most; if symptomatic, can be treated with steroids'''
* '''<span style="color:#ff0000">Ureteral contusion''' 
** '''Can occur in the context of a gunshot wound with blast injury'''
** '''Complications may include delayed ureteral stricture and/or overt ureteral necrosis with urinary extravasation'''
*'''<span style="color:#ff0000">Preoperative ureteral stenting'''
** '''<span style="color:#ff0000">May increase intraoperative recognition of ureteral injury'''
** '''<span style="color:#ff0000">A [https://pubmed.ncbi.nlm.nih.gov/19165412/ randomized trial] demonstrated that prophylactic stenting does not reduce the risk of ureteral injury in women undergoing gynecologic surgery'''
** Ureteral stents are not without complications

=== Diagnosis and evaluation ===

==== <span style="color:#ff0000">History and physical exam ====

* Hematuria is a non-specific indicator of urologic injury 
* '''Significant ureteral injury can occur in the absence of hematuria'''
* '''<span style="color:#ff0000">Post-operative signs and symptoms of missed ureteral injury (6):''' 
*#'''<span style="color:#ff0000">Flank pain'''
*# '''<span style="color:#ff0000">Fever'''
*# '''<span style="color:#ff0000">Leukocytosis'''
*# '''<span style="color:#ff0000">Ileus'''
*# '''<span style="color:#ff0000">Abdominal distention'''
*# '''<span style="color:#ff0000">Urinary fistula'''

==== <span style="color:#ff0000">Imaging ====

* '''<span style="color:#ff0000">Indications (contrast enhanced CT with 10 minute delayed films) for imaging (1)''' (AUA)
*# '''Stable trauma patients with suspected ureteral injuries and not proceeding directly to laparotomy'''
**If the initial delayed images do not adequately opacify the ureters, further delayed imaging may be necessary if ureteral injury is still suspected.

* '''<span style="color:#ff0000">Findings suggestive of ureteral injury (4):''' 
*#'''<span style="color:#ff0000">Contrast extravasation'''
*# '''<span style="color:#ff0000">Lack of contrast in the ureter distal to the suspected injury'''
*# '''<span style="color:#ff0000">Ipsilateral delayed pyelogram'''
*# '''<span style="color:#ff0000">Ipsilateral hydronephrosis'''

==== <span style="color:#ff0000">Other</span> ====

* '''<span style="color:#ff0000">Direct inspection during laparotomy in trauma patients with suspected ureteral injury who have not had preoperative imaging</span>'''

=== [https://www.aast.org/resources-detail/injury-scoring-scale#ureter AAST Grading] ===

* '''Grade I: contusion or hematoma without devascularization'''
* '''Grade II: laceration with < 50% transection'''
* '''Grade III: laceration with ≥ 50% transection'''
* '''Grade IV: laceration with complete transection and < 2cm devascularization'''
* '''Grade V: laceration with avulsion and > 2cm of devascularization'''
<nowiki>*</nowiki>Advance one grade for bilateral injury up to grade III

=== <span style="color:#ff0000">Management ===

* '''<span style="color:#ff0000">Based on hemodynamic stability'''
** '''<span style="color:#ff0000">If hemodynamically stable:'''
*** '''<span style="color:#ff0000">Traumatic ureteral lacerations should be repaired immediately'''
**** '''<span style="color:#ff0000">A longitudinal laceration is converted into a transverse one''' '''so as not to narrow the ureteral lumen (Heineke-Mikulicz procedure)'''
** '''<span style="color:#ff0000">If hemodynamically unstable: temporary urinary drainage followed by delayed definitive repair'''
*** '''<span style="color:#ff0000">Options for temporary urinary drainage (4):'''
***# '''<span style="color:#ff0000">Ureteral stent''' (internalized double J or exteriorized single J) '''only'''
***# '''<span style="color:#ff0000">Short period of observation with a plan for reoperation when the patient is more stable, usually within 24 hours'''
***# '''<span style="color:#ff0000">Exteriorize the ureter'''
***# '''<span style="color:#ff0000">Tie off the ureter''' (with long silk sutures for easy identification at time of delayed repair) '''<span style="color:#ff0000">and plan percutaneous nephrostomy'''
**** Definitive repair of the injury should be performed when patient has improved/stabilized
* '''<span style="color:#ff0000">Special scenarios'''
** '''<span style="color:#ff0000">Ureteral contusion'''
*** '''<span style="color:#ff0000">Options, depending on ureteral viability and clinical scenario (2):'''
***# '''<span style="color:#ff0000">Ureteral stenting'''
***# '''<span style="color:#ff0000">Resection with primary repair'''
**** '''<span style="color:#ff0000">Indications for resection with primary repair (2):'''
****# '''<span style="color:#ff0000">Severe or large areas of contusion'''
****# '''<span style="color:#ff0000">Gun-shot related ureteric contusions'''
****#* '''<span style="color:#ff0000">With a gun-shot related injury, excise devitalized tissue and an adjacent segment of normal-appearing ureter to eliminate late ischemia and stricture formation from the blast effect.''' Once both ends of the ureter have been adequately trimmed to healthy areas, mobilized, and correctly oriented, they are spatulated for ≈5-6 mm. Spatulation is performed for both ureteral segments at 180° apart
**** '''<span style="color:#ff0000">In ureteral contusions that do not appear to require excision/anastomosis, a ureteral stent should be placed'''; only truly minor injuries can go untreated, but the patients should be watched for signs of delayed urine leak.
** '''<span style="color:#ff0000">Delayed diagnosis''': '''ureteral stent'''
*** '''If ureteral stent placement unsuccesful or not possible''' (proximal ureter is completelely transected or patient instability preculdes attempts at retrograde placement)''', perform percutaneous nephrostomy with delayed repair'''
**** If nephrostomy alone does not adequately control the urine leak, options then include placement of a periureteral drain or immediate open ureteral repair
*** '''Indications for immediate repair for delayed diagnosis (within 1 week of injury) (2):'''
***# '''Injury located near a surgically closed viscus, such as bowel or vagina'''
***# '''Patient is being re-explored for other reasons'''
*** '''<span style="color:#ff0000">Campbell's 11th edition: postoperatively discovered injuries should be immediately repaired when detected within 72 hours.'''
** '''<span style="color:#ff0000">Endoscopic injury: ureteral stent +/- percutaneous nephrostomy tube'''
*** Ureteral perforation during ureteroscopy can be treated by ureteral stenting, usually with no subsequent complications
*** If endoscopic or percutaneous procedures are not possible or fail to adequately divert the urine, open or laparoscopic repair may be performed.
** '''<span style="color:#ff0000">Ureterovaginal fistula: ureteral stent'''
*** In females who undergo vaginal surgery (such as hysterectomy) or sustain penetrating pelvic trauma involving the vagina, an initially unrecognized ureteral injury can present in a delayed manner with ureterovaginal fistula.
*** Success rates range from64%-100% for ureterovaginal fistula who are initially managed with ureteral stent placement
*** Patients who failed with ureteral stent insertion went on to undergo ureteral reimplantation with or without Boari flap or psoas hitch, or transureteroureterostomy with success rates approaching 100%
** '''<span style="color:#ff0000">Ligation of the ureter: removal ligature and observe the ureter for viability'''
*** '''<span style="color:#ff0000">If viability uncertain, perform ureteroureterostomy or ureteral reimplantation'''
** '''Ureteroarterial fistula'''
*** '''A rare and potentially catastrophic condition that should be diagnosed and treated immediately because it can cause life-threatening hematuria'''
*'''<span style="color:#ff0000">Principles of managing the injured ureter:'''
*# '''Mobilize''' '''the injured ureter''', sparing the adventitia widely, so as not to devascularize the ureter further
*# '''Debride the ureter''' '''minimally''' but judiciously until edges bleed, especially in gunshot wounds
*# '''Repair ureters with spatulated, tension-free, stented, watertight anastomosis, using fine absorbable monofilament''' such as 5-0 polydioxanone (PDS) and retroperitoneal '''drainage''' afterward. Use optical magnification if necessary.
*# '''Retroperitonealize the ureteral repair''' by closing peritoneum over it if possible
*# Do not tunnel ureteroneocystostomies but rather create a widely spatulated nontunneled anastomosis
*# '''With severely injured ureters, blast effect, concomitant vascular surgery, and other complex cases, consider omental interposition to isolate the repair when possible'''
* '''<span style="color:#ff0000">Surgical management'''
** '''<span style="color:#ff0000">See [[Ureteric Stricture Disease|Ureteric Stricture Disease Chapter Notes]]'''
** '''<span style="color:#ff0000">Options for repair/reconstruction,</span> choice depends on location and length of injury'''
*** '''<span style="color:#ff0000">Upper ureteral injuries (above iliac vessesls)'''
***# '''<span style="color:#ff0000">Ureterocalycostomy'''
***# '''<span style="color:#ff0000">Ureter-ureterostomy'''
***# '''<span style="color:#ff0000">Trans-ureterostomy'''
***# '''<span style="color:#ff0000">Ileal or other interposition (not recommended in acute setting)'''
***# '''<span style="color:#ff0000">Autotransplant (not recommended in acute setting)'''
***# '''Rarely, acute nephrectomy is required to treat ureteral injury after external violence'''
*** '''<span style="color:#ff0000">Lower ureteral injuries (below iliac vessesls)'''
***# '''<span style="color:#ff0000">Ureteroneocystostomy'''
***# '''<span style="color:#ff0000">Psoas hitch'''
***# '''<span style="color:#ff0000">Boari flap'''
** '''<span style="color:#ff0000">Follow-up after repair'''
*** '''<span style="color:#ff0000">6 weeks: remove stent'''
**** At the time of stent removal, retrograde ureterogram can be perform to document healing without leakage or stenosis.
*** 10 weeks: furosemide (Lasix) renogram can document that the system continues to be unobstructed.
*** 4 months: renal US can document lack of hydronephrosis, which itself might indicate late obstruction