gms | German Medical Science

GMS Current Posters in Otorhinolaryngology - Head and Neck Surgery

German Society of Oto-Rhino-Laryngology, Head and Neck Surgery (DGHNOKHC)

ISSN 1865-1038

Eliciting the swallowing reflex by mucosal stimulation during sleep in humans – preliminary results

Poster Schlafmedizin

  • Joachim T. Maurer - Universitäts-HNO-Klinik Mannheim, Mannheim
  • Wondi Tesfayesus - MedEl, Innsbruck, Österreich
  • J. Ulrich Sommer - Universitäts-HNO-Klinik Mannheim, Mannheim
  • Willard Wilson - MedEl, Innsbruck, Österreich
  • Mohammed Mousa - Hochschule Mannheim, Mannheim

GMS Curr Posters Otorhinolaryngol Head Neck Surg 2016;12:Doc085

doi: 10.3205/cpo001436, urn:nbn:de:0183-cpo0014360

Published: April 11, 2016

© 2016 Maurer et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. See license information at http://creativecommons.org/licenses/by/4.0/.


Outline

Abstract

Decreased sensitivity of the pharyngeal mucosa is thought to impair protective upper airway reflexes and play a role in increased airway collapsibility in OSA subjects during sleep. We report here on the sensitivity to pharyngeal electrical stimulation as measured by the elicited swallow reflex in waking and sleeping OSA subjects.

In addition to a fully attended polysomnography according to AASM standard, patients received a transnasally inserted 3-channel esophageal pressure catheter in order to detect swallowing. Furthermore, it contained 10 electrode rings at equal distances distributed throughout the pharynx. Electrical stimuli were applied using various contacts and amplitudes. Swallowing thresholds and response rates were obtained during wakefulness and compared to swallow responses elicited during sleep.

In this ongoing study, 6 OSA patients (1 f, 5 m; age 33-67, BMI 25-39 ) were enrolled so far. The mean stimulation thresholds during wakefulness were ranging from 2.2 to 3.9 mA. Sleep stage had a profound effect on the response rate to pharyngeal stimulation. During sleep, swallows were elicited in N1 by 23.2%, in N2 by 12.5%, in N3 by 8.8%, and in REM by 22% of the stimuli. The majority of the swallows were elicited during a respiratory event related arousal, although swallow could also be elicited during normal sleep.

Our preliminary findings suggest that the threshold for swallowing elicited by electrical stimulation of the mucosa is lowest at the tongue base level. During sleep, there was a high interindividual variability in reflex behavior. Nevertheless, swallow reflexes seem to be evoked best during superficial sleep but rarely found in deep sleep. This sleep stage dependency could be due to changing mucosal thresholds and/or central reflex patterns.

Supported by: MedEL, Innsbruck, Österreich

Der Erstautor weist auf folgenden Interessenkonflikt hin: JT Maurer hat Reisekostenunterstützung von MedEl im Rahmen des Forschungsprojektes erhalten.