Muscle sympathetic nerve activity during apneic episodes in patients with obstructive sleep apnea syndrome.

Abstract Muscle sympathetic nerve activity (MSNA) was recorded from peroneal from peroneal nerve in 4 OSAS patients during sleep. During apneic episode, MSNA was enhanced, but it did not increase progressively toward the end of the apneic episode. MSNA remained at a stable level in the later part of an apneic episode. A surge of MSNA took place just preceding or just at the end of an apneic episode and it was followed by a transient marked blood pressure elevation.