ACUTE NECROTIZING MYOPATHY OF INTENSIVE-CARE - ELECTROPHYSIOLOGICAL STUDIES

A series of recent reports have identified cases of a quadriplegic myo pathy characterized by myofiber necrosis and loss of myosin filaments associated with the use of nondepolarizing muscle blocking agents and glucocorticoids. We report electrophysiological findings in 7 intensiv e care unit patients who developed evidence of an acute myopathy in as sociation with the use of nondepolarizing muscle blocking agents Sever al important features were identified: (i) a neuromuscular transmissio n deficit was observed in 3 patients up to 7 days following withdrawal of vecuronium; (ii) motor M potentials were of low amplitude, there w as mild abnormal spontaneous activity on needle electromyography, and sensory conduction was relatively preserved; (iii) not ail patients re ceived glucocorticoids or were asthmatic; (iv) 2 patients given vecuro nium had Very high creatine kinase levels and developed acute renal fa ilure associated with myoglobinuria; and (v) rises in motor M potentia ls accompanied clinical recovery. This complication of intensive care may be severe, but is reversible and possibly avoidable. Our findings implicate nondepolarizing muscle blocking agents in the development of the myopathy. Electrophysiological studies provide important prognost ic guidance. (C) 1994 John Wiley and Sons, Inc.