Bombings: Injury Patterns and Care Seminar Curriculum Guide

3. 
   Explain the pathophysiology of crush injury.
   

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  lower extremities
  
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  upper extremities
  
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  pelvis
  
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  gluteal region
  
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  abdominal muscles
  

Early mortality in untreated crush injury is due to hyperkalemia and hypovolemia. Late mortality is due to renal failure, coagulopathy and hemorrhage, and sepsis.

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  Skeletal muscle damage is greatest after reperfusion.
  
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  Super-oxide radicals produced during reperfusion attack free fatty acids, producing cellular edema, death, and necrosis.
  
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  Na-K-ATP pump exchanges intracellular sodium for calcium with further derangement of intracellular metabolism.
  

There is cardiovascular instability due to massive fluid shift, electrolyte abnormalities, and direct myocardial toxicity.

Calcium  Hypocalcemia  Arrythmias

Phosphate  Hyperphosphatemia  Renal damage

Myoglobin  Myoglobinemia  Renal damage

Fluid shifts  Hypovolemia  Renal failure

Reperfusion  Free radicals  Renal damage

Purines  Hyperuricemia  Renal damage

Hypoxemia  Lactic acid  Acidosis

Thromboplastin  Complement system  DIC

Creatinine  Elevated serum levels