ELECTRICAL-STIMULATION OF UPPER AIRWAY MUSCULATURE

Investigators have postulated that pharyngeal collapse during sleep in patients with obstructive sleep apnea (OSA) may be alleviated by stim ulating the genioglossus. The effect of electrical stimulation (ES) of the genioglossus on pharyngeal patency was examined in an isolated fe line upper airway preparation and in apneic humans during sleep. We fo und that stimulation of the genioglossus (n = 8) and of the hypoglossa l nerve (n = 1) increased maximum airflow through the isolated feline upper airway in humans during sleep. Additional findings in the isolat ed feline upper airway suggest that such increases in airflow were due to decreases in pharyngeal collapsibility. The evidence suggests that improvements in airflow dynamics with electrical stimulation are due to selective recruitment of the genioglossus, rather than due to nonsp ecific activation of the pharyngeal musculature or arousal from sleep. The implications of these results for future therapy with ES are disc ussed.