Morphological and histochemical study of nonhemiplegic muscle in acute stroke patients manifesting respiratory failure.

There is little information on skeletal muscle changes in patients with acute stroke. We performed morphological and histochemical examinations of nonhemiplegic sternothyroid muscles biopsied at the time of tracheostomy from 13 patients with acute stroke manifesting acute respiratory failure. Degenerating and regenerating fibers were observed in all 13 specimens. Following characteristic myopathic changes suggestive of mitochondrial abnormalities were also demonstrated in a majority of patients. Namely, ragged-red fibers, focal increase in NADH-TR activity in subsarcolemmal areas and increases in acid phosphate activity were found. The changes were similar but extremely slight in control patients with acute respiratory failure due to causes other than stroke and were absent in the other control patients with adenomatous thyroid tumor. The severity and extent of the histopathological changes in the muscle fibers in patients with acute stroke were closely correlated with the duration of hypoxemia but not with such items as type of stroke, site of cerebral lesion, consciousness level, days of biopsy after the stroke, clinical outcome, levels of serum creatine kinase, myoglobin and PaO2. This acute nonhemiplegic muscle involvement was considered to be a very common complication in severe stroke patients.