AUA: Urotrauma (2020)

Link to Original AUA Guideline (literature search up to February 2020)

*****All information below contained in more comprehensive Trauma: Upper Urinary Tract and Trauma: Lower Urinary Tract Notes

Renal Trauma

• The kidneys are particularly prone to deceleration injuries (e.g. falls, motor vehicle collisions) because they are fixed in space only by the renal pelvis and the vascular pedicle
• Diagnosis and Evaluation
  • History and physical exam
  • Imaging
    • Indications for imaging (contrast enhanced CT with immediate and delayed flims) in stable trauma patients (5):
      1. Gross hematuria
      2. Microscopic hematuria and systolic blood pressure < 90mmHG
      3. Mechanism concerning for renal injury (e.g., rapid deceleration, significant blow to flank)
      4. Physical exam findings concerning for renal injury (e.g. rib fracture, significant flank ecchymosis)
      5. Penetrating injury of abdomen, flank, or lower chest
         • Generally, children can be imaged using the same criteria as adults. Children, however, often do not exhibit hypotension as adults do.
    • Modality
      • CT abdomen/pelvis with IV contrast (with immediate and delayed images) should be performed when there is suspicion of renal injury
        • In children, ultrasound may be used, although CT is preferred
        • An intraoperative one-shot IVP (2 mL/kg IV bolus of contrast with a single image obtained 10-15 minutes later) may be used to confirm that a contralateral functioning kidney is present in rare cases where the patient is taken to the operating room without preliminary CT scan if surgeons are considering renal exploration or nephrectomy
• Management
  • AUA: Based on hemodynamic stability
    • If hemodynamically stable: non-invasive management
      • Non-invasive managment includes close hemodynamic monitoring, bed rest, ICU admission, and blood transfusion (when indicated)
      • Patients initially managed noninvasively may still require surgical, endoscopic, or angiographic treatments at a later time, especially those with higher grade injuries.
        • Although devitalized parenchyma has been suggested as a risk factor for development of septic complications, evidence supporting intervention for this radiographic finding is inconclusive.
    • If hemodynamically unstable: immediate intervention (surgery or angioembolization)
      • For hemodynamically unstable patients with radiographic findings of large perirenal hematoma (> 4 cm) and/or vascular contrast extravasation in the setting of deep or complex renal laceration (AAST Grade 3-5), surgeons should perform immediate intervention
        • Perinephric hematoma size provides a rough radiographic estimate of the magnitude of renal bleeding, and increasing hematoma size has been incrementally associated with higher intervention rates.
      • Selected patients with bleeding from segmental renal vessels may benefit from angioembolization as an effective yet minimally invasive treatment to control bleeding
        • Selective embolization provides an effective and minimally invasive means to stop active bleeding from parenchymal lacerations and segmental arterial injury
      • Patients who are hemodynamically unstable despite active resuscitation should be taken to the operating room rather than angiography
  • Surgical management
    • Nephrectomy is a frequent result when hemodynamically unstable patients undergo surgical exploration
• Renal injury with urinary extravasation
  • Stable patients where renal pelvis or proximal ureteral injury is not suspected: observation
    • Parenchymal collecting system injuries often resolve spontaneously.
  • Indications for intervention (3):
    1. Presence of complications such as fever, infection, increasing pain, ileus, or fistula.
    2. Suspected injury to renal pelvis or proximal ureteral avulsion
       • Suggested by large medial urinoma or contrast extravasation on delayed images without distal ureteral contrast)
    3. Urinoma increasing in size, purulence, or complexity on follow-up imaging
  • Options for intervention
    • Ureteral stent (preferreed)
      • An internalized ureteral stent is minimally invasive and alone may provide adequate drainage of the injured kidney
      • A period of concomitant Foley catheter drainage may minimize pressure within the collecting system and enhance urinoma drainage
    • Percutaneous urinoma drain, percutaneous nephrostomy, or both may also be necessary
    • Mangement of injury to the renal pelvis or proximal ureteral avulsion may be endoscopic vs. open, depending on the clinical scenario
• Follow-up in patient's managed non-operatively
  • Indications for follow-up CT imaging (after 48 hours) in renal trauma patients (2): (AUA)
    1. Clinical signs of complications (e.g., fever, worsening flank pain, ongoing blood loss, abdominal distention)
    2. Deep lacerations (AAST Grade IV-V)
       • AAST Grade IV-V renal injuries are prone to developing troublesome complications such as urinoma or hemorrhage
       • AAST Grade I-III injuries have a low risk of complications and rarely require intervention. Routine follow-up CT imaging is not advised for uncomplicated AAST Grade I-III injuries because it is not likely to change clinical management in these cases

Ureteral trauma

• Ureteral injuries are rare, accounting for 1% of urologic injuries.
• Ureteral injuries tend to be iatrogenic, occurring during gynecologic, urologic, or colorectal surgery.
• The majority of ureteral injuries originating outside of the operating room are a result of penetrating trauma

• Diagnosis and evaluation
  • History and physical exam
    • Absence of hematuria cannot be relied upon to exclude ureteral injury
  • Imaging
    • Indications (contrast enhanced CT with 10 minute delayed films) for imaging (1)
      1. 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.
    • Findings suggestive of ureteral injury (4):
      1. Contrast extravasation
      2. Lack of contrast in the ureter distal to the suspected injury
      3. Ipsilateral delayed pyelogram
      4. Ipsilateral hydronephrosis
  • Other
    • Direct inspection during laparotomy in trauma patients with suspected ureteral injury who have not had preoperative imaging
• Management

• • Based on hemodynamic stability
    • If hemodynamically stable:
      • Traumatic ureteral lacerations should be repaired immediately
    • If hemodynamically unstable: temporary urinary drainage followed by delayed definitive management
      • In damage control settings when immediate ureteral repair is not possible at time of initial laparotomy, urinary extravasation can be prevented with ureteral ligation followed by
        1. Percutaneous nephrostomy tube placement
        2. Externalized ureteral catheter secured to the proximal end of the ureteral defect
      • Definitive repair of the injury should be performed when patient has improved/stabilized
  • Special scenarios
    • Ureteral contusion
      • Options, depending on ureteral viability and clinical scenario (2):
        1. Ureteral stenting
        2. Resection with primary repair
        • Indications for resection with primary repair (2):
          1. Severe or large areas of contusion
          2. Gun-shot related ureteric contusions
    • 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):
        1. Injury located near a surgically closed viscus, such as bowel or vagina
        2. Patient is being re-explored for other reasons
    • Endoscopic injury: ureteral stent +/- percutaneous nephrostomy tube
      • If endoscopic or percutaneous procedures are not possible or fail to adequately divert the urine, open or laparoscopic repair may be performed.
    • 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%
  • Options for repair
    • Ureteral injuries located proximal to the iliac vessels: primary repair over a ureteral stent, when possible
      • When the ureter is injured above the iliac vessels, a spatulated, tension-free primary ureteral repair over a ureteral stent is advisable after all non-viable ureteral tissue has been judiciously debrided.
      • In situations where the anastomosis cannot be performed without tension, mobilization of the ureter should be performed in a manner that preserves maximal ureteral blood supply.
      • If an anastomosis can still not be performed after mobilization, a ureteral reimplantation can be attempted, incorporating ancillary maneuvers such as a bladder psoas hitch and/or Boari bladder flap.
      • Interposition with bowel and auto-transplant are not recommended in the acute setting
      • If the injury cannot be managed adequately in the acute setting, ureteral ligation with percutaneous nephrostomy tube placement is advised followed by delayed ureteral reconstruction.
    • Ureteral injuries located distal to the iliac vessels: ureteral reimplantation or primary repair over a ureteral stent, when possible
      • Tension-free reimplantation may require ancillary maneuvers such as a bladder mobilization with psoas hitch or flap

Bladder trauma

• Bladder rupture can occur into the peritoneal cavity (intraperitoneal bladder rupture) or outside the peritoneal cavity (extraperitoneal rupture).
  • Bladder injuries are:
    • Extraperitoneal in ≈60%
    • Intraperitoneal in ≈30%
    • Both intraperitoneal and extraperitoneal in ≈10%

• Diagnosis and Evaluation
  • History and physical exam
    • Indicators of potential bladder rupture (9):
      1. Gross hematuria
         • Most common indicator of bladder injury
         • A limited number of pelvic fracture patients with bladder injuries will present with microscopic hematuria
      2. Abdominal distention
      3. Suprapubic pain
      4. Inability to void
      5. Low urine output
      6. Pubic symphysis diastasis
      7. Obturator ring fracture displacement >1 cm
      8. Increased creatinine and BUN (secondary to peritoneal absorption of urine)
      9. Intraperitoneal low density free fluid on abdominal imaging (urinary ascites)
  • Imaging
    • Indications for cystography in stable patients
      • 2020 AUA Guidelines
        • Absolute (1):
          1. Gross hematuria and pelvic fracture
        • Relative (2):
          1. Gross hematuria and a mechanism concerning for bladder injury
          2. Pelvic ring fractures and clinical indicators (see above) of bladder rupture
             • The vast majority of bladder injuries are associated with pelvic fractures because the bladder is well protected within the pelvis, however, pelvic fracture alone does not warrant radiologic evaluation of the bladder
  • Modality: retrograde cystography (CT or plain film)
    • Critical as it can determine the presence of an injury and whether it is intraperitoneal or extraperitoneal.
    • Plain film and CT cystography have similar specificity and sensitivity, and are both highly accurate for the diagnosis of bladder rupture
    • Technique
      • The volume instilled should be a minimum of 300 mL or until the patient reaches tolerance in order to maximally distend the bladder
        • Clamping a Foley catheter to allow excreted IV-administered contrast to accumulate in the bladder is not appropriate.
      • With plain film cystography, a minimum of 2 views are required, the first at maximal fill and the second after bladder drainage.

• Managment
  • Based on extraperitoneal vs. intraperitoneal
    • Uncomplicated extraperitoneal bladder ruptures: Foley catheter left in place 2-3 weeks
      • In the setting of significant concurrent injuries, it is acceptable to leave the catheter in longer.
      • Campbell’s 11th edition: if a pelvic hematoma is present, antimicrobial agents are started on the day of injury and continued for at least 1 week to prevent infection of the hematoma
      • Consideration for open repair may be appropriate in those patients with non-healing bladder injuries who are unresponsive to Foley catheter drainage >4 weeks.
      • Follow-up cystography
        • Should be done to confirm that the injury has healed with catheter drainage
    • Intraperitoneal bladder rupture: prompt surgical repair
      • Failure to repair intraperitoneal bladder injuries can result in peritonitis (from translocation of bacteria from the bladder to the abdominal cavity), sepsis, and other serious complications
      • Repair may need to be delayed in the unstable patient
      • Follow-up cystography
        • Should be done in complex repairs
        • May not be necessary in more simple repairs
  • Indications for immediate surgical repair of bladder (7)§: Immediate Bladder Repair NOVA
    1. Intraperitoneal bladder rupture
    2. Exposed Bone spicules in the bladder lumen
    3. Concurrent Rectal injury; may lead to fistula formation to the ruptured bladder
    4. Bladder Neck injuries; may not heal with catheter drainage alone and repair should be considered
    5. Patient undergoing Open reduction internal fixation; to reduce risk of infection to hardware)
    6. Concurrent Vaginal injury; may lead to fistula formation to the ruptured bladder
    7. Patient undergoing repair ofAbdominal injuries, consider performing bladder repair for extraperitoneal bladder injury given that the typical bladder repair can be performed quickly and with little morbidity.
    • Follow-up cystography should be used to confirm that the complex, extraperitoneal bladder injury has healed
  • Surgical management
    • The integrity of the bladder neck and ureteral orifices should be confirmed and repair considered if injured
    • Following surgical repair for bladder injuries, urethral catheter drainage alone without suprapubic (SP) cystostomy is recommended
      • Studies have shown no advantage of combined SP and urethral catheterization
      • Exceptions in which combined SP and urethral catheterization may be considered (3):
        1. Patients requiring long-term catheterization, such as those with severe neurological injuries (i.e., head and spinal cord), those immobilized due to orthopedic injuries
        2. Complex bladder repairs with tenuous closures
        3. Significant hematuria

Urethral trauma

• Background
  • Urethral injuries may be partial or complete disruption of the urethra
  • Male urethral injuries are classified as posterior (at or above the membranous urethra) vs. anterior urethra (penile or bulbar urethra)
• Pathogenesis
  • Posterior injuries
    • Almost exclusively associated with pelvic fractures
      • In females, urethral injuries occur almost exclusively as a result of pelvic fracture
  • Anterior injuries
    • May be blunt (e.g., straddle injuries, where the urethra is crushed between the pubic bones and a fixed object) or penetrating, and the urethra may be lacerated, crushed, or disrupted.
    • Most commonly involves bulbar urethra since it is most susceptible to compressive injury due to its fixed location beneath the pubis
• Diagnosis and Evaluation
  • History and physical exam
    • Indicators of urethral trauma (5):
      1. Blood at the urethral meatus (most common finding)
      2. Inability to urinate
      3. Perineal/genital ecchymosis
      4. In males, high-riding prostate on physical exam
      5. In females, labial edema and/or blood in the vaginal vault

• • Imaging
    • Modality: retrograde urethrogram (RUG)
      • See figure of retograde urethrogram of traumatic proximal urethral injury
      • Should be performed immediately when urethral injury is suspected

• • • • • May demonstrate partial or complete urethral disruption, providing guidance for how to best manage bladder drainage in the acute setting
        • Blind catheter passage prior to RUG should be avoided, unless exceptional circumstances indicate an attempt at emergent catheter drainage for monitoring
          • Patients with pelvic fracture urethral injury (PFUI) are often unable to urinate due to their injuries. Trauma resuscitations typically involve aggressive hydration and a critical need to closely monitor patient volume status
          • In the acute setting of a partial urethral disruption, a single attempt with a well-lubricated catheter may be attempted by an experienced team member.
      • Technique
        1. Position the patient obliquely with the bottom leg flexed at the knee and the top leg kept straight
           • If severe pelvic or spine fractures are present, leaving the patient supine and placing the penis on stretch to acquire the image is appropriate.
        2. Introduce a catheter tipped syringe or a 12Fr Foley catheter into the fossa navicularis
        3. Place the penis on gentle traction
        4. Inject 20-25 mL undiluted water-soluble contrast material and capture images
      • Occasionally a Foley catheter has been placed before evaluating the urethra
        • If no meatal blood is present and suspicion of injury is low, further imaging is not warranted.
        • If blood is present, a pericatheter RUG should be performed to identify potential missed urethral injury.
          • A pericatheter RUG can be done by injecting contrast material through a 3Fr catheter or angiocatheter held in the fossa navicularis to distend the urethra and prevent contrast leak per meatus.
• Management
  • Regardless of the type of injury, securing catheter drainage of the bladder is the immediate goal of treatment.
  • Male
    • Posterior injuries
      • Pelvic fracture urethral injury: immediate suprapubic tube (pecutaneous or open) with delayed repair
        • SPT remains the gold standard for urinary drainage.
        • Attempts at immediate sutured repair of posterior urethral injury are associated with unacceptably high rates of erectile dysfunction and urinary incontinence.
        • If the bladder is displaced due to pelvic hematoma, bladder localization techniques such as aspiration with an 18 G spinal needle or imaging with ultrasound or fluoroscopy may facilitate percutaneous SPT insertion.
        • 14 Fr or larger Foley catheter is preferred
        • May be placed in patients undergoing open reduction internal fixation (ORIF) for pelvic fracture
          • No evidence to indicate that SPT insertion increases the risk of orthopedic hardware infection.
        • Most PFUI patients will develop obliterative strictures which are amenable to open posterior urethroplasty
        • Primary realignment vs. suprapubic tube
          • Primary realignment refers to advancing a urinary catheter across the ruptured urethra
            • The technique of PR may require two urologists to navigate the urethra simultaneously from above and below with multiple flexible or rigid cystoscopes, video monitors, and fluoroscopy.
            • The Emergency Department setting is inappropriate for primary realignment of most PFUI.
            • Prolonged attempts at endoscopic realignment in patients with PFUI should be avoided.
          • May be associated with less severe urethral strictures compared to patients undergoing suprapubic tube alone; however, has been associated with a longer clinical course due to multiple procedures required for recurrent obstruction over an extended timeline.
          • Even if primary alignment successful, patients with pelvic fracture associated urethral injury are at high risk for developing urethral stricture, and suprapubic tube trainage should be maintained while awaiting resolution of PFUI.
        • Complications of posterior urethral injury and it's repair (3):
          1. Urethral stricture
          2. Erectile dysfunction
          3. Incontinence
          • Patients should be followed for at least 1 year following urethral injury to monitor for development of complications
            • Surveillance strategies for stricture recommended for the first year after injury include uroflowmetry, retrograde urethrogram, cystoscopy, or some combination of methods.
            • Stricture can be treated with urethroplasty or direct vision internal urethrotomy
          • Impotence and incontinence are generally considered to be caused by the pelvic fracture itself rather than contemporary interventions for PFUI.
    • Anterior injuries
      • Straddle injury to the anterior urethra: prompt urinary drainage (SPT or PR) with delayed repair
        • With straddle injury, immediate operative intervention with to repair or debride the injured urethra is contraindicated due to the indistinct nature of the injury border.
        • For major straddle injuries involving the urethra, initial SPT is the standard of care; however, PR has shown promising results with respect to stricture rate and erectile dysfunction in patients with straddle injuries of lesser magnitude.
        • Stricture formation after straddle injury is very high and thus all patients require follow-up surveillance using uroflowmetry, retrograde urethrogram and/or cystoscopy.
      • Penetrating trauma: prompt surgical repairs should be performed in patients with uncomplicated penetrating (including gunshot) trauma of the anterior urethra
        • Spatulated primary repair of uncomplicated injuries in the acute setting offers superior outcomes to delayed reconstruction.
        • Surgical repair should not be undertaken if the patient is unstable, the surgeon lacks expertise in urethral surgery or in the setting of extensive tissue destruction or loss

Genital trauma

• Background
  • Clinicians should initiate ancillary psychological, interpersonal, and/or reproductive counseling and therapy for patients with genital trauma when loss of sexual, urinary, and/or reproductive function is anticipated.
• Penile trauma
  • Penile fracture
    • Definition of penile fracture: disruption of the tunica albuginea with rupture of the corpus cavernosum
    • Pathogenesis
      • Most commonly occurs during vigorous sexual intercourse
    • Diagnosis and Evaluation
      • History and physical exam
        • History
          • Indicators of penile fracture
            1. Penile ecchymosis or swelling (most common symptoms)
            2. Cracking, popping, or snapping sound during intercourse or manipulation and immediate detumescence.
            3. Penile pain
            4. Penile angulation
        • Physical exam
      • Imaging
        • The typical history and clinical presentation of penile fracture usually make adjunctive imaging studies unnecessary. However, when the history and physical examination are equivocal for penile fracture, imaging can establish the diagnosis.
        • Options (2):
          1. Ultrasound (preferred)
             • Preferred over MRI because it is rapid, readily available, noninvasive, inexpensive, and accurate
             • Most useful for ruling out fracture in patients with low clinical suspicion or to identify the location of the tear, potentially guiding the choice of incision
          2. Penile-perineal MRI
        • If imaging is equivocal or diagnosis remains in doubt, surgical exploration should be performed
      • Other
        • Endoscopy
          • Should be performed given that urethral injury occurs in 10-22% of cases of penile fracture
    • Management
      • Suspected penile fractures should be promptly explored and surgically repaired
      • Technique
        • Incision: ventral midline or circumcision incision.
        • Tunical repair is performed with absorbable suture and should be performed at the time of presentation to improve long-term patient outcomes.
  • Concomitant urethral injury
    • In patients with penile fracture or penetrating trauma who present with blood at the urethral meatus, gross hematuria or inability to void, evaluate for concomitant urethral injury.
      • All but the most superficial injuries should be evaluated for urethral injury
      • Options for evaluation include urethroscopy and retrograde urethrogram)
  • Amputation
    • A rare injury that is usually self-inflicted and associated with extreme mental illness.
    • Every attempt should be made to locate, clean, and preserve the severed portion in a “double bag” technique.
      • The distal penis should be rinsed in saline solution, wrapped in saline-soaked gauze, and sealed in a sterile plastic bag, and the bag should be placed into an outer bag with ice or slush.
    • Urologists should perform re-anastomosis of macroscopic structures, including the corpora cavernosa, spatulated repair of the urethra, and skin, when the amputated penis is available.
    • A microvascular surgeon should be consulted whenever possible to perform microscopic repair of dorsal arteries, veins, and nerves.

• Testicular trauma
  • Blunt scrotal trauma may lead to rupture of the tunica albuginea of the testicle.
  • Diagnosis and evaluation
    • History and physical exam
      • History
      • Physical exam
        • Clinical examination of the scrotum following trauma can be limited due to significant scrotal swelling and patient discomfort
    • Imaging
      • Modality: ultrasound
        • Can reliably diagnose testicular rupture with a high level of accuracy in the setting of blunt scrotal trauma.
          • The utility of scrotal ultrasound for the evaluation of testicular rupture in the setting of penetrating scrotal trauma is limited.
        • Ultrasound findings suggestive of testicular fracture include (2):
          1. Heterogeneous pattern of the testicular parenchyma
          2. Disruption of the testicular contour/tunica albuginea
  • Management
    • Indications for scrotal exploration (5):
      1. Imaging findings of testicular rupture
      2. Equivocal imaging but suspected testicular rupture
      3. Large hematoma
      4. Clear physical findings of testicular rupture
      5. Penetrating scrotal injuries
         • Inspect for testicular, vascular and vasal injury; >50% will have testicular rupture
    • In patients with confirmed testicular rupture, perform debridement of non-viable tissue with tunical closure (when possible) or orchiectomy (when non-salvagable)
      • A flap or graft of tunica vaginalis may be used to cover a large defect in the tunica albuginea in an otherwise salvageable testis
    • Early exploration and repair may prevent complications, such as ischemic atrophy of the testis and infection.

• Genital skin loss
  • In patients with extensive genital skin loss or injury from infection, shearing injuries, or burns (thermal, chemical, electrical), perform exploration and limited debridement of non-viable tissue
    • Genital skin is well vascularized and tissues with marginal viability may survive due to collateral blood flow.
    • Typically, these injuries require multiple procedures in the operating room prior to definitive reconstructive procedures.
    • Wound management can include a variety of methods including gauze dressings with frequent changes, silver sulfadiazine or topical antibiotic and occlusive dressing, or negative pressure dressings.
    • Reconstructive techniques for definitive repair include primary closure and advancement flaps, placement of skin grafts, free tissue flaps, and pedicle based skin flaps

Questions

See Trauma: Upper Urinary Tract and Trauma: Lower Urinary Tract Notes

References

• Morey, Allen F., et al. "Urotrauma guideline 2020: AUA guideline." The Journal of urology 205.1 (2021): 30-35.