Deglutition and Respiratory Patterns During Sleep

Abstract

An overview is presented of a study of deglutition, electroencephalographic arousal and respiratory phase patterns during sleep.
During sleep, swallowing was infrequent and absent for long periods. The mean number of swallows per hour during the total sleep time was 2.4±1.0. The mean longest deglutition-free period was 68.8 minutes. Most deglutition occurred in association with spontaneous electroencephalographic arousal. Deglutition was related to the sleep stage. The deeper the sleep stage, the lower the mean deglutition frequency. The deeper the sleep stage, the lower the mean arousal frequency, and the lower the mean ratio of arousal with deglutition to arousal. Approximately 60% of swallows were followed by arrested breathing and approximately 25% by expiration. Clearance of the pharynx and esophagus by sleep-related deglutition was reduced. However, the pharyngeal stage of sleep-related deglutition was almost always followed by arrested breathing and expiration, reducing the risk of aspiration.
Deglutition was infrequent and displayed a unique pattern in patients with obstructive sleep apnea syndrome during sleep. Most deglutition occurred in association with respiratory electroencephalographic arousal after apnea or hypopnea. Approximately 70% of swallows were followed by inspiration.
CPAP therapy improves not only apnea-hypopnea during sleep and sleep structure but also sleep-related deglutition, especially respiratory phase patterns associated with deglutition.