Rhabdomyolysis

• Rhabdomyolysis involves skeletal muscle breaking down and releasing various chemicals into the blood.
• Myocytes undergo cell death ( apoptosis ), releasing: Myoglobin, Potassium, Phosphate, Creatine kinase, Potassium is the most immediately dangerous breakdown product.
• Hyperkalaemia can cause cardiac arrhythmias and cardiac arrest.
• These breakdown products can cause acute kidney injury.
• Myoglobin, in particular, is toxic in high concentrations.
• Impaired renal function results in further accumulation of these substances in the blood.
• Myoglobinuria refers to myoglobin in the urine, giving urine a red-brown colour.
• Signs and symptoms of rhabdomyolysis include muscle pain, muscle weakness, muscle swelling, reduced urine output, red-brown urine, fatigue, nausea and vomiting, confusion, and others.
• Urea and electrolytes (U&E) are required for acute kidney injury and hyperkalaemia.
• Rhabdomyolysis can be caused by anything that causes significant damage to muscle cells, such as prolonged immobility, extremely rigorous exercise, crush injuries, seizures, statins, and others.
• Creatine kinase (CK) is the crucial diagnostic blood test for rhabdomyolysis, with normal levels being less than around 150 U/L and levels in rhabdomyolysis being 1,000-100,000 U/L.
• A urine dipstick will be positive for blood in the presence of myoglobinuria.