Crush Syndrome Bombings earthquakes building collapse train accidents

Crush Syndrome (壓碎症候群)

Bombings, earthquakes, building collapse, train accidents and mining accidents. Crush injuries may result in fatal injury or severe metabolic abnormalities that may result in death. Careful monitoring of these patients is essential.

定 義 肌肉, 皮膚因直接壓傷, 造成體亦 由血管露出, 產生水腫變化 並經由血液再灌注 (reperfusion) 的機轉 造成全身性多系統損傷 edema (excess fluid), oliguria (abnormally low excretion of urine) symptoms of renal failure.

症 狀 limb may be tingling or numb swollen and hard tissue around injured body part bruising and formation of blisters body part may be pale and cool if arteries are compressed victim may feel weak or faint pulse becomes weak and rapid victim may become anxious or restless.

致病機轉（1） leaking of Na+, Cl-, & water into the sarcoplasm hypovolemic and hemodynamic shock prerenal and later acute renal failure intracompartmental hypertension

致病機轉（2） leaking of Ca 2+into the sarcoplasm hypocalcemia (<6 mg/dl) aggravate hyperkalemic with cardiotoxicity activation of cytotoxic proteases

致病機轉（3） efflux of K+ hyperkalcemia and cardiotoxicity peripheral vasodilation

致病機轉（4） release of purines from affected muscle hyperuricemia (often > 20 mg/dl) nephrotoxicity

致病機轉（5） Phosphorus hyperphosphatemia aggravate hypocalcemia metastatic calcification, including the kidney

致病機轉（6） Myoglobin Nephrotoxicity, particularly with coexisting oliguria, aciduria and hyperuricosuria

致病機轉（7） Lactic acid metabolic acidosis; aciduria Thromboplastin D. I. C. Creatine kinase extreme elevation Creatinine creatinine/urea ratio

Actions of Mannitol in the Prophylaxis of Post-traumatic Acute Renal Failure （1） Extra-renal : Extracellular volume expansion with attendant increase in cardiac output and stabilization of mean arterial pressure Increased cardiac contractility Stimulation of atrial natriuretic factor release Reduction of skeletal cell edema and decompression of muscle tamponade in the compartment syndrome Restoration of contractility to the dilated blood vessels in crushed muscles

Actions of Mannitol in the Prophylaxis of Post-traumatic Acute Renal Failure （2） Renal : Decrease in blood viscosity & oncotic pressure across the glomerulus, causing an increase in glomerular filtration rate Dilation of glomerular capillaries and stimulation of prostaglandin E and I release Increase in proximal intratubular pressure and flow and prevention of obstruction Possible reduction of tubular cell swelling and injury Scavenging of oxygen free radicals

Actions of Mannitol in the Prophylaxis of Post-traumatic Acute Renal Failure （3） Dangers : Hyperosmolar volume overload in oligoanuria Massive IV doses of mannitol ( >200 g/d) have been reported to cause acute renal failure; this type of ARF is promptly reversible after hemodialysis

治療腔室症候群的建議 a conservative approach is suggested !! Decompression could be achieved by intravenous hypertonic mannitol that can be readily judged within ~40 minutes by relief of symptoms and measurable shrinkage of the swollen limb. Surgical fasciotomy as a measure of last resort for refractory cases