TY - JOUR

T1 - Upper Esophageal Sphincter Response to Laryngeal Adductor Reflex Elicitation in Humans

AU - Meisoll, Frederik Joshua

AU - Jungheim, Michael

AU - Fast, Jacob Friedemann

AU - Miller, Simone

AU - Ptok, Martin

N1 - Funding Information: The authors would like to acknowledge the kind support by the Central Research Devices Service Unit of Hannover Medical School, which enabled image and pressure signal synchronization, a fundamental element of the present study. The authors would also like to thank Professor Dr.-Ing. Tobias Ortmaier and Assistant Professor Dr.-Ing. L?der Alexander Kahrs for supporting this study and Editage for correction of the English text. Author Contributions. f.j.m.: acquisition, analysis, and interpretation of data, statistics, drafting of the manuscript. m.j.: study concept and design, supervision of acquisition of data, analysis and interpretation of data, statistics, drafting of the manuscript. j.f.f.: technical support, interpretation of data, revision of the manuscript. s.m.: interpretation of data, revision of the manuscript. m.p.: study concept and design, interpretation of data, revision of the manuscript. f.j.m. and m.j. contributed equally to this manuscript and share first authorship. Open access funding enabled and organized by Projekt DEAL. Open access funding enabled and organized by Projekt DEAL.

PY - 2021/5/6

Y1 - 2021/5/6

N2 - Objective: The laryngeal adductor reflex (LAR) is an important mechanism to secure the airways from potential foreign body aspiration. An involvement of the upper esophageal sphincter (UES) in terms of a laryngo-UES contractile reflex has been identified after laryngeal mucosa stimulation. However, the LAR–UES relationship has not yet been fully explained. This study aimed to determine the magnitude, latency, and occurrence rate of the UES pressure response when the LAR is triggered in order to elucidate the functional relationship between the larynx and the UES. Methods: This prospective study included seven healthy volunteers (5 female, 2 male, age 22–34 years). Laryngeal penetration was simulated by eliciting the LAR 20 times in each individual by applying water-based microdroplets onto the laryngeal mucosa. UES pressures were measured simultaneously using high-resolution manometry. Results: Two distinct pressure phases (P1, P2) associated with the LAR were identified. P1 corresponded with a short-term UES pressure decrease in two subjects and a pressure increase in five subjects occurring 200 to 500 ms after the stimulus. In P2, all subjects experienced an increase in UES pressure with a latency time of approximately 800 to 1700 ms and an average of 40 to 90 mmHg above the UES resting tone. Conclusion: Foreign bodies penetrating the laryngeal inlet lead to a reflex contraction of the UES. Phase P1 could be a result of vocal fold activity caused by the LAR, leading to pressure changes in the UES. The constriction during P2 could strengthen the barrier function of the UES in preparation to a subsequent cough that may be triggered to clear the airways. Level of Evidence: 4 Laryngoscope, 131:E1778–E1784, 2021.

AB - Objective: The laryngeal adductor reflex (LAR) is an important mechanism to secure the airways from potential foreign body aspiration. An involvement of the upper esophageal sphincter (UES) in terms of a laryngo-UES contractile reflex has been identified after laryngeal mucosa stimulation. However, the LAR–UES relationship has not yet been fully explained. This study aimed to determine the magnitude, latency, and occurrence rate of the UES pressure response when the LAR is triggered in order to elucidate the functional relationship between the larynx and the UES. Methods: This prospective study included seven healthy volunteers (5 female, 2 male, age 22–34 years). Laryngeal penetration was simulated by eliciting the LAR 20 times in each individual by applying water-based microdroplets onto the laryngeal mucosa. UES pressures were measured simultaneously using high-resolution manometry. Results: Two distinct pressure phases (P1, P2) associated with the LAR were identified. P1 corresponded with a short-term UES pressure decrease in two subjects and a pressure increase in five subjects occurring 200 to 500 ms after the stimulus. In P2, all subjects experienced an increase in UES pressure with a latency time of approximately 800 to 1700 ms and an average of 40 to 90 mmHg above the UES resting tone. Conclusion: Foreign bodies penetrating the laryngeal inlet lead to a reflex contraction of the UES. Phase P1 could be a result of vocal fold activity caused by the LAR, leading to pressure changes in the UES. The constriction during P2 could strengthen the barrier function of the UES in preparation to a subsequent cough that may be triggered to clear the airways. Level of Evidence: 4 Laryngoscope, 131:E1778–E1784, 2021.

KW - Upper esophageal sphincter

KW - airway-protective mechanism

KW - high-resolution manometry

KW - laryngeal adductor reflex

KW - laryngo-UES contractile reflex

UR - http://www.scopus.com/inward/record.url?scp=85094646438&partnerID=8YFLogxK

U2 - 10.1002/lary.29166

DO - 10.1002/lary.29166

M3 - Article

VL - 131

SP - E1778-E1784

JO - Laryngoscope

JF - Laryngoscope

SN - 0023-852X

IS - 6

ER -