rhabdomyolysis
Table of Contents
rhabdomyolysis
introduction
- skeletal muscle necrosis may cause death either by:
- releasing heme pigments such as myoglobin into the circulation which may result in acute renal failure, particularly if there is hypovolaemia and poor renal flow.
- releasing potassium and phosphate into the circulation causing hyperkalaemia and hyperphosphataemia
- severe hypocalcaemia due to deposition of calcium salts in damaged muscle and decreased bone responsiveness to parathyroid hormone
- localised necrosis may also cause odema resulting in compartment syndrome
- low likelihood of acute renal failure when peak creatine kinase levels are under 5,000 - 10,000 U/L
- A problem that is unique to rhabdomyolysis-induced acute renal failure is the development of hypercalcaemia during the recovery phase in approximately 20 to 30 percent of patients
aetiology
mechanical injury
- traumatic crush injury, particularly those trapped in vehicles after motor vehicle accidennts, or in collapsed buildings from earthquakes
- prolonged muscle ischaemia from immobilisation such as patients lying comatose for hours before being found
- prolonged ischaemia from tourniquets or muscle compression such as during prolonged surgical procedures
- near drowning causing prolonged hypoxia &/or vasoconstriction
- prolonged use of massage guns
exertional
- untrained individuals over-exerting themselves
metabolic
- inherited disorders of glycogenolysis, glycolysis, or lipid or purine metabolism
drug-related
- coma induced by alcohol, opioid overdose, or other CNS depressants (as above)
- direct myotoxins such as statins, colchicine, alcohol binges
- metabolic poisons such as carbon monoxide
toxins
- mushroom poisoning
- toxic shock syndrome
infections
- acute viral infections due to a variety of viruses, including influenza, Coxsackievirus, Epstein-Barr, Herpes simplex virus (HSV), parainfluenza, adenovirus, echovirus, HIV / AIDS, and cytomegalovirus (CMV)
- bacterial pyomyositis
- septicaemia
- faciparum malaria
vaccinations
- rarely may occur after vaccinations
electrolyte and endocrine disorders
inflammatory myopathies
- dermatomyositis
- polymyositis
ED Mx of rhabdomyolysis
- in the emergent Mx of a limb that is crushed, predict potential of life threatening hyperkalaemia and cardiac arrest on return of circulation once the limb is released
- be aware - check CK level in those at risk
- treat underlying cause
- ensure adequate saline rehydration to prevent renal failure - start early - consider 1-2L/hour iv 0.9% saline initially if fluid overload is not a risk. Adjust to maintain the desired diuresis of approximately 200 to 300 mL/hour.
- cardiac monitor and check FBE, U&E, CK
- monitor fluid balance and urine output
- consider attempted prevention of acute renal failure with forced mannitol-alkaline diuresis in an effort to diminish the renal toxicity of myoglobin.
- Mx acute renal failure (ARF) if occurs as usual but watch for hypercalcaemia thus avoid giving calcium in Mx
rhabdomyolysis.txt · Last modified: 2021/11/14 04:32 by gary1