Neuromuscular function in survivors of the acute respiratory distress syndrome

Background. Survivors of acute respiratory distress syndrome (ARDS) report generalized weakness and reduced exercise tolerance up to two years following, discharge from the intensive care unit (ICU). Persistent neuromuscular complications of ARDS may contribute to the functional disability observed in these patients. Methods: Sixteen ARDS survivors underwent comprehensive neurological evaluation and standardized electrodiagnostic testing 6 to 24 months after ICU discharge. Four of these patients agreed to open muscle biopsy. Results: Seven of sixteen patients had clinically significant focal compressive mononeuropathies. Electrodiagnostic testing failed to reveal any changes attributable to critical illness polyneuropathy or myopathy. All four muscle biopsies were abnormal, and although the pathological features were structurally non-specific, the presence of an acquired myopathy remains possible. Four patients had persistent mixed sensory complaints but had normal electrodiagnostic evaluation. Conclusions: The high frequency of mononeuropathies highlights the need for vigilance in daily ICU care. The findings also suggest that complaints of weakness and reduced exercise capacity in ARDS survivors may be related to combined effects of compressive neuropathies and generalized longstanding structural changes in muscle and may support an organic basis for longterm functional disability.