<s>[INST] context: Acute renal failure Crush Syndrome Severe systemic manifestation of trauma and ischaemia involving soft tissues, principally skeletal muscle, due to prolonged severe crushing. - It leads to increased permeability of the cell membrane and to the release of potassium, enzymes, and myoglobin from within cells. Ischaemic renal dysfunction secondary to hypotension and diminished renal perfusion results in acute tubular necrosis and uraemia." Pathophysiology Crush injury can follow prolonged continuous pressure on muscle tissue. Crush injury can lead to crush syndrome. Ischaemia reperfusion (when the pressure is released. from the crushed limb) is the main mechanism of muscle injury in crush syndrome. There is traumatic rhabdomyolysis. Rhabdomyolysis is the breakdown of muscle fibres with the leakage of potentially toxic cellular contents into the systemic circulation. Muscle injury causes large quantities of potassium, phosphate, myoglobin, creatine kinase and urate to leak into the circulation. Myoglobin levels in the plasma are normally very low. If a significant amount of skeletal muscle is damaged (>100 g) excess myoglobin is .filtered by the kidneys and can cause renal tubular obstruction and renal damage: the excess myoglobin is nephrotoxic. intravascular volume depletion and renal hypoperfusion, combined with myoglobinuria, result in renal dysfunction.2 Crush syndrome is characterised by Hypovolaemic shock (due to sequestration of water in the injured muscle cells). Hyperkalaemia (release of cellular potassium by the injured muscle cells). This can also lead to: - Metabolic acidosis (release of cellular phosphate and sulphate by the injured muscle cells) - Acute renal failure - Disseminated intravascular coagulation (DIC) The key clinical_ features of crush syndrome are : Crushing injury to a large mass of skeletal muscle. Sensory and motor disturbances in the compressed limbs, which subsequently become tense and swollen Myoglobinuria and/or haemoglobinuria Raised creatine kinase There may be oliguria Elevated levels of urea, creatinine, uric acid, potassium, phosphate Thpocalcaemia [/INST] question: 28 year old male met with an accident and sustained severe crush injury. He is most likely develop aEUR' | options: A: Acute renal failure B: Hypophosphtemia C: Hypercalcemia D: Acute myocardial infarction | answer: A </s>