critical illness myopathy
Also written as: CIM — critical illness myopathy
Acute muscle weakness and atrophy developing in critically ill patients, often associated with sepsis and corticosteroid use.
Full Definition
Critical illness myopathy (CIM) is an acquired condition characterized by acute onset of muscle weakness and atrophy in patients hospitalized in intensive care units. This disorder typically develops in the setting of sepsis, multiple organ failure, and prolonged mechanical ventilation, often exacerbated by corticosteroid and neuromuscular blocking agent use. CIM primarily affects limb and respiratory muscles, leading to difficulty weaning from mechanical ventilation and prolonged weakness. Electrophysiological studies show reduced compound muscle action potential amplitudes with preserved nerve conduction velocities. Muscle biopsy reveals selective loss of thick (myosin) filaments. Recovery is variable and may take months to years.
Usage
Usage note: Distinguish from critical illness polyneuropathy, which affects peripheral nerves rather than muscle.
In Context
- "The patient developed critical illness myopathy after prolonged ICU stay with sepsis." — Hospital discharge summary
- "EMG findings were consistent with CIM rather than polyneuropathy." — Electromyography report