title: Electrophysiology of neuromuscular disorders in critical illness.
abstract: BACKGROUND
  Neuromuscular disorders, predominantly critical illness myopathy (CIM) and critical illness polyneuropathy (CIP) occur in approximately one-third of patients in intensive care units. The aim of this study was to review the important role of electrophysiology in this setting.
  
  
  RESULTS
  In CIM, sarcolemmal inexcitability causes low amplitude compound muscle action potentials (CMAPs) that may have prolonged durations. Needle electrode examination usually reveals early recruitment of short duration motor unit potentials, often with fibrillation potentials. In CIP, the findings are usually those of a generalized axonal sensorimotor polyneuropathy. Direct muscle stimulation aids in differentiating CIP and CIM and in identifying mixed disorders along with other electrodiagnostic and histopathologic studies. Identifying evolving reductions in fibular CMAP amplitudes in intensive care unit (ICU) patients predicts development of neuromuscular weakness.
  
  
  CONCLUSIONS
  Knowledge of the various neuromuscular disorders in critically ill patients, their risk factors, and associated electrodiagnostic findings can lead to development of a rational approach to diagnosis of the cause of neuromuscular weakness in ICU patients.
authors: Department of Neurology, University of Pittsburgh School of Medicine, 200 Lothrop Street, F878, Pittsburgh, Pennsylvania 15213, USA. lacomisd@upmc.edu
authors: David
authors: D
authors: Lacomis
mesh_terms: D000818:Animals; D003422:Critical Care; D016638:Critical Illness; D004195:Disease Models, Animal; D004558:Electric Stimulation; D004568:Electrodiagnosis; D055724:Electrophysiological Phenomena; D006801:Humans; D018908:Muscle Weakness / Q000209:etiology / Q000503:physiopathology; D009135:Muscular Diseases / Q000209:etiology / Q000503:physiopathology; D019148:Neuromuscular Blockade; D009468:Neuromuscular Diseases / Q000150:complications / Q000453:epidemiology / Q000503:physiopathology* / Q000517:prevention & control; D011115:Polyneuropathies / Q000209:etiology / Q000503:physiopathology; D016896:Treatment Outcome