Reperfusion Injury / Crush Injury


- See: Compartment Syndrome

- Discussion:
    - traumatic rhabdomyolysis, or crush syndrome, is consequence of prolonged continuous pressure on the limbs;
    - it reflects disintegration of muscle tissue & influx of myoglobin, potassium, and phosphorus into the circulation;
    - syndrome is characterized by hypovolemic shock and hyperkalemia;
    - these results strongly suggest that free-radical scavengers are beneficial in attenuating or preventing reperfusion-induced injury to ischemic skeletal muscles and consequently to other organs, particularly the kidneys;
    - these scavengers should be administered before crushed muscles are decompressed or as early as possible during reperfusion in order to prevent irreversible damage to ischemic cells;

- Labs:
    - urine myoglobin;
    - serum CPK
    - chemistry panel

- Treatment:
    - fluid requirements:
         - it is quite common in extensive traumatic rhabdomyolysis for muscles of 75-kg adult to sequester greater/= 12 liters of fluid over 48-hour period (i.e., mount of same order of magnitude as entire volume of extracellular fluid);
         - if inadequately corrected, this potentially fatal hypovolemia may cause renal ischemia by activating secretion of constrictor hormones, such as angiotensin II, atecholamines, vasopressin, and intrarenal thromboxane;
    - alkalinization of urine;
          - bicarbonate
          - acetazolamide
    - medical therapy:
          - mannitol
               - scavenger of hydroxyl free radicals, & allopurinol, xanthine oxidase inhibitor & protects against myocardial necrosis;
               - scavengers also limit tissue injury during ischemia & reperfusion of intestine, the kidney, liver, and island skin flaps;
         - allopurinol
               - benzamil
               - amiloride
               - KCl-sparing diuretic drug, decreases intracellular sodium concentration & inhibits Na-hydrogen & Na-calcium exchange in many tissues;
    - renal failure
               - pathogenesis of renal failure in rhabdomyolysis and the crush syndrome is still not fully understood;
               - direct toxic effects of myoglobin or products of decomposition;
               - dehydration is predisposing factor for renal failure;
    - avoid IV Ca:
               - unless there is danger of hyperkalemic arrhythmia, infusion of calcium is not indicated;
               - unless calcium is constantly infused, its administration will correct hypocalcemia only temporarily; most infused calcium is deposited in injured muscles, thus aggravating rhabdomyolysis & causing metastatic calcification;
    - metastatic calcification:
               - danger that mild metabolic alkalosis resulting from mannitol-alkaline diuresis therapy may enhance metastatic calcification



Mechanisms of Disease: The Role Of Reperfusion-Induced Injury In The Pathogenesis Of The Crush Syndrome
 
Lower limb compartment syndrome: course after delayed fasciotomy.
 
Military–Civilian Collaboration in Trauma Care and the Senior Visiting Surgeon Program

Reperfusion pulmonary edema.

Reperfusion injury in skeletal muscle: a prospective study in patients with acute limb ischaemia and claudicants treated by revascularization

Deferoxamine attenuates ischemia-induced reperfusion injury in the skin and muscle of myocutaneous flaps in the pig.

Blockade of complement activation prevents local and pulmonary albumin leak after lower torso ischemia-reperfusion.

Identification of xanthine oxidase activity following reperfusion in human tissue.



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Tuesday, September 4, 2012 1:06 pm