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Crush syndrome (also ''traumatic rhabdomyolysis'' or ''Bywaters' syndrome'') is a medical condition characterized by major shock and renal failure after a crushing injury to skeletal muscle. Crush ''injury'' is compression of extremities or other parts of the body that causes muscle swelling and/or neurological disturbances in the affected areas of the body, while crush ''syndrome'' is localized crush injury with systemic manifestations. Cases occur commonly in catastrophes such as earthquakes, to victims that have been trapped under fallen or moving masonry. Victims of crushing damage present some of the greatest challenges in field medicine, and may be among the few situations where a physician is needed in the field. The most drastic response to crushing under massive objects may be field amputation. Even if it is possible to extricate the patient without amputation, appropriate physiological preparation is mandatory: where permissive hypotension is the standard for prehospital care, fluid loading is the requirement in crush syndrome. ==Pathophysiology== Seigo Minami, a Japanese physician, first reported the crush syndrome in 1923.〔Medical discoveries - Who and when- Schmidt JF. Springfield: CC Thomas, 1959. p.115.〕〔Morton's medical bibliography -An annotated check-list of texts illustrating History of medicine (Garrison-Morton). Aldershot: Solar Press; 1911. p.654.〕 He studied the pathology of three soldiers who died in World War I from insufficiency of the kidney. The renal changes were due to methohemoglobin infarction, resulting from the destruction of muscles, which is also seen in persons who are buried alive. The progressive acute renal failure is because of acute tubular necrosis. The syndrome was later described by British physician Eric Bywaters in patients during the 1941 London Blitz. It is a reperfusion injury that appears after the release of the crushing pressure. The mechanism is believed to be the release into the bloodstream of muscle breakdown products—notably myoglobin, potassium and phosphorus—that are the products of rhabdomyolysis (the breakdown of skeletal muscle damaged by ischemic conditions). The specific action on the kidneys is not understood completely, but may be due partly to nephrotoxic metabolites of myoglobin. The most devastating systemic effects can occur when the crushing pressure is suddenly released, without proper preparation of the patient, causing reperfusion syndrome. Without proper preparation, the patient, with pain control, may be cheerful before extrication, but die shortly thereafter. This sudden decompensation is called the "smiling death." These systemic effects are caused by a traumatic rhabdomyolysis. As muscle cells die, they absorb sodium, water and calcium; the rhabdomyolysis releases potassium, myoglobin, phosphate, thromboplastin, creatine and creatine kinase. Compartment syndrome can be secondary to crush syndrome. Monitor for the classic 5 P’s: pain, pallor, parasthesias, pain with passive movement, and pulselessness. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Crush syndrome」の詳細全文を読む スポンサード リンク
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