Clinical utility of bedside electromyography in critical ill with suspected neuromuscular diseases / 中华神经科杂志

ABSTRACT

Objective To investigate the utility of bedside electromyography (EMG) in diagnosis and management of critical illness patients with suspected neuromuscular diseases.Methods Bedside EMG was performed in 34 critical illness patients with weakness and respiratory involvement,including segmental motor nerve conduction studies,sensory nerve conduction studies,F waves,concentric needle EMG and repetitive nerve stimulation.The clinical manifestations and clinical utility of bedside EMG in critical illness patients with suspected neuromuscular diseases were analyzed. Results EMG was normal in 5 patients.Low-frequency repetitive nerve stimulation showed decrement response of compound muscle action potential (CMAP) in 4 of 8 patients.Motor nerve conduction studies showed CMAP amplitude decreased in 73.3％(22/30) patients,and demyelinating changes was detected in 20.0％ (6/30)patients.F-wave persistence was 0 in 55.0％ (11/20) patients.Amplitude of sensory nerve action potential decreased in 28.6％ (6/21)patients.Bedside EMG could help to confirm or exclude diagnoses and guide the management in 82.4％(28/34) patients,confirm the diagnoses of peripheral neuropathy but have no effect on management in 11.8％ (4/34) patients,and bedside EMG was inconclusive in 2 patients.Conclusions Bedside EMG is useful for the diagnosis and management of critical ill with suspected neuromuscular diseases,while motor nerve conduction studies and repetitive nerve stimulation are more valuable.Individualized protocol for EMG studies should be made on the basis of clinical problem.