Impact of oropharyngeal muscle tone over the fluid retention in the upper airway during supine position in healthy men

• Grant number: 14/02881-7
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): October 01, 2014
• Effective date (End): September 30, 2015
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal researcher: Geraldo Lorenzi Filho
• Grantee: Beatriz Antipou dos Santos
• Home Institution: Instituto do Coração Professor Euryclides de Jesus Zerbini (INCOR). Hospital das Clínicas da Faculdade de Medicina da USP (HCFMUSP). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Obstructive sleep apnea (OSA) is a common respiratory disorder characterized by recurrent narrowing and occlusion of the upper airway during sleep. A recent study demonstrated that oropharyngeal exercises decrease the severity of OSA. However, the mechanisms of this new therapy are unknown. Recent works suggest that the supine position causes movement of fluid to the neck and contributes to the obstruction of the upper airway. The aim of this work is to test the hypothesis that the increased oropharyngeal muscle tone during the supine position reduces the fluid retention in the upper airways and results in higher patency and lower airway collapsibility. Fifteen healthy male adults will remain in the supine position for one hour in two independent experiments (randomized sequence): with or without activation of the upper airway muscles. Subjects will be monitored via Electrical Impedance Tomography (method being developed in the Sleep Laboratory - Incor), Segmental Bioimpedance and upper airway collapsibility (Negative Expiratory Pressure - NEP). The outcome variables are: Total cervical impedance (infers variation of fluid in the upper airway), cervical luminal impedance (infers a variation of the upper airway lumen), regional impedance (infers the amount of liquid in the upper airway) and NEP (infers the collapsibility of the upper airway). The study will contribute to understanding the role of the upper airway muscle tone in fluid accumulation of cervical region.