Rosen & Barkin's 5-Minute Emergency Medicine Consult (608 page)

• In 1989, Mee et al. published the hallmark article (10-yr prospective study) that established guidelines for the evaluation and treatment of blunt renal trauma:
  
  • Major renal lacerations represent significant reparable renal injuries.
    
  • Adult patients at risk for having sustained major lacerations:
    
    • Gross hematuria,
      or
      
    • Microhematuria (≥3–5 RBCs/HPF) with shock (systolic BP ≤90 mm Hg) in the field or on arrival in the ED,
      or
      
    • History of sudden deceleration without hematuria or shock
      
• IV contrast-enhanced CT scan is the procedure of choice in identifying urologic injury.
  
• Guidelines are not applicable in cases of penetrating renal trauma or in children.
  
• Adults with blunt renal trauma and gross hematuria, or microhematuria in the presence of shock, require renal imaging for further evaluation of renal injury.
  
• In adults with penetrating renal trauma, significant injuries to the kidney and ureter can occur without hematuria:
  
  • Location of penetrating wound in relation to urinary tract is the most important factor in deciding need for radiographic imaging.
    
  • Penetrating injuries with any degree of hematuria should be imaged.
    
• Important to rule out coexisting injuries
  

• Urinalysis: Gross hematuria or >50 RBCs/HPF in adults and >20 RBC/HPF in children is suggestive of renal injury.
  
• Baseline lab values including hematocrit and BUN/creatinine should be obtained.
  

• Plain abdominal films:
  
  • May show fractured inferior ribs or transverse processes, a unilateral enlarged kidney shadow, or obscuring of the psoas margin
    
• IV pyelogram (IVP):
  
  • Bolus infusion IVP with nephrotomography study of choice in institutions without 24-hr availability of CT
    
  • Rapid injection of 1.5–2 mL of contrast material per kilogram of body weight to a maximum or 150 mL after obtaining a preliminary kidney, ureter, and bladder image
    
  • Postinfusion supine film is obtained followed by 1-, 2-, and 3-min supine films.
    
    • Allows evaluation for renal viability and function
      
    • Extravasation reflects injury to the collecting system.
      
    • Nonvisualization of a kidney may indicate renal pedicle injury or parenchymal shattering.
      
    • Abnormal findings are often nonspecific and require more definitive studies.
      
• Ultrasound:
  
  • Role in evaluation of renal injury is controversial
    
  • Routinely performed at bedside in trauma patients as part of focused assessment with sonography in trauma (FAST)
    
  • May show size of perirenal hematoma and whether it is expanding or resolving
    
  • Low sensitivity for identification of retroperitoneal free fluid
    
  • Otherwise, exam is nonspecific and does not provide enough information
    
• CT scan:
  
  • An IV contrast-enhanced helical CT scan is the diagnostic procedure of choice.
    
  • Superior anatomic detail and diagnostic accuracy of 98% for renal injury
    
  • Sensitive indicator of minor extravasation, parenchymal laceration, vascular injury, and nonrenal injuries
    

• Major blunt renal trauma can occur in the absence of gross hematuria or shock (as children have a high catecholamine output after trauma, which maintains BP until ∼50% of blood volume has been lost).
  
• Meta-analysis has defined 50 RBC/HPF as the microscopic quantity below which imaging can be omitted and no significant injuries missed.
  
• CT scan is the imaging modality of choice.
  

• Renal parenchymal injury
  
• Renal vascular injury
  
• Ureteral injury
  
• Bladder or urethral injury
  

TREATMENT

• Obtain details of injury from pre-hospital providers.
  
• IV access
  
• Penetrating wounds or evisceration should be covered with sterile dressings.
  

• Airway management (including C-spine immobilization)
  
• Standard Advanced Trauma Life Support (ATLS) resuscitation measures:
  
  • Adequate IV access, including central lines and cutdowns, as dictated by the patient’s hemodynamic status
    
  • Fluid resuscitation, initially with 2 L of crystalloid (NS or lactated Ringer solution), followed by blood products as needed
    
• Rule out potential life-threatening injuries 1st.
  

• Immediate laparotomy in the acutely injured patient who is hemodynamically unstable with presumed hemoperitoneum and renal injury
  
• Significant injuries (grades II–V) are found in only 5.4% of renal trauma cases.
  
• 98% of blunt renal injuries can be managed nonoperatively.
  
• ∼80–90% of renal injuries have major associated organ injury that can affect the choice of renal injury management.
  
• Angiography and selective renal embolization has an increasing role and is an alternative treatment to laparotomy in patients not requiring immediate surgery.
  
• Penetrating renal trauma:
  
  • Previously exploratory laparotomy was recommended for all patients with penetrating renal injuries.
    
  • Nonoperative management has become more accepted for grades I–III with penetrating renal injuries in the absence of associated intra-abdominal injury or hemodynamic instability
    
• Blunt renal trauma:
  
  • Isolated renal injury without significant associated injuries occurs more commonly from blunt trauma, and in most circumstances, can be managed nonoperatively.
    
  • Classes I and II: Contusions and minor lacerations with stable vital signs and urographically normal renal function can be managed nonoperatively.
    
  • Class III: Renal lacerations with urinary extravasation:
    
    • Controversy between operative vs. nonoperative management
      
    • Management should be based on degree of injury using CT scanning.
      
  • Classes IV and V: Shattered kidney or renal pedicle injuries and hemodynamically unstable patients require emergent laparotomy.
    
  • All ureteral injuries require operative repair.
    

FOLLOW-UP

Patients with significant renal injury require hospitalization for definitive laparotomy or observation.

• Adult trauma patients without hematuria, shock, or no renal injury confirmed radiographically
  
• Adult blunt trauma patient with microhematuria (≥3–5 RBCs/HPF) but no shock (systolic BP ≤90 mm Hg)
  
• Pediatric blunt trauma patient with ≤50 RBC/HPF and no other coexisting major organ injuries
  

• Outpatient referral to urologist should be made for microhematuria to ensure that it does not represent a more serious underlying condition.
  
• Urinoma formation is the most common complication (1–7%) of patients with renal trauma:
  
  • Urinary extravasation resolves spontaneously in 76–87% of cases
    

• Broghammer JA, Fisher MB, Santucci RA. Conservative management of renal trauma: A review.
  Urology
  . 2007;70(4):623–629.
  
• Mee SL, McAninch JW, Robinson AL, et al. Radiographic assessment of renal trauma: A 10-year prospective study of patient selection.
  J Urol
  . 1989;141:1095–1098.
  
• Santucci RA, Wessells H, Bartsch G, et al. Evaluation and management of renal injuries: Consensus statement of the renal trauma subcommittee.
  BJU Int
  . 2004;93(7):937–954.
  
• Shoobridge JJ, Corcoran NM, Martin KA, et al. Contemporary management of renal trauma.
  Rev Urol
  . 2011;13(2):65–72.
  
• Tinkoff G, Esposito TJ, Reed J, et al. American Association for the Surgery of Trauma Organ Injury Scale I: Spleen, liver, and kidney, validation based on the National Trauma Data Bank.
  J Am Coll Surg.
  2008;207(5):646–655.
  

CODES

• 866.00 Injury to kidney without mention of open wound into cavity, unspecified injury
  
• 866.01 Injury to kidney without mention of open wound into cavity, hematoma without rupture of capsule
  
• 866.02 Injury to kidney without mention of open wound into cavity, laceration
  

BASICS

• Cardiac reperfusion therapy is required on patients that present with ST-segment elevation myocardial infarction (STEMI)
  
• Early percutaneous coronary intervention (PCI), but not fibrinolytics may be considered in those with unstable angina (UA)/non–ST-segment elevation MI (NSTEMI)
  
• Fibrinolytic therapy:
  
  • Reduces morbidity and mortality in STEMI in cases that PCI is not available in <120 min
    
  • The earlier fibrinolytics are started, the more myocardium is salvaged
    
  • Goal of fibrinolytic therapy is a door-to-needle time of 30 min if PCI is not planned or delayed >120 min
    
• PCI:
  
  • Balloon inflation, stent placement, and thrombus removal are possible options in the cath lab and result in overstretching of vessel wall and partial disruption of intima, media, and adventitia, resulting in enlargement of lumen and outer diameter of diseased vessel and restoration of epicardial coronary arterial flow
    
  • Goal of primary PCI is a door-to-balloon time of 90 min from 1st medical contact for STEMI or <120 min if at a non-PCI center
    
  • Stent placement decreases early and late loss in luminal diameter seen with percutaneous transluminal coronary angioplasty (PTCA).
    
  • PCI provides greater coronary patency and thrombolysis in MI flow than do fibrinolytics and decreased mortality and morbidity
    
  • Lower risk of bleeding than with fibrinolytics
    
  • Immediate knowledge of extent of disease
    
  • PCI should be strongly considered within 1st 48 hr after NSTEMI in discussion with a cardiologist
    
• Glycoprotein IIb/IIIa inhibitors:
  
  • Antiplatelet agents that bind to platelet receptor glycoprotein IIb/IIIa and inhibit platelet aggregation
    
  • Reduce mortality and reinfarction rate in patients in whom PCI is planned; reasonable to administer at time of primary PCI
    
  • Not indicated for patients with STEMI, unless also undergoing PCI
    
• Unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH):
  
  • Adjuncts in treatment with aspirin, clopidogrel, fibrinolytics, glycoprotein IIb/IIIa inhibitors, and PCI
    
  • Anticoagulant therapy with either UFH or LMWH is indicated in patients with either STEMI (with PCI or fibrinolytics) or UA/NSTEMI
    
• Clopidogrel or Prasugrel should be added to standard therapy regardless of whether PCI or reperfusion therapy is planned.
  
• Statin therapy reduces clinical events in patients with stable coronary artery disease. This may also extend to patients experiencing an acute ischemic coronary event
  
• Post arrest patients may have therapeutic hypothermia initiated in the ED prior to PCI or during PCI