A computational model of upper airway respiratory function with muscular coupling

Area of Science:

• Biomechanics
• Computational Fluid Dynamics
• Respiratory Physiology

Background:

• Upper airway collapse during sleep is a significant health concern, particularly in obstructive sleep apnea.
• Understanding the interplay between anatomy, posture, and muscle activity is crucial for developing effective interventions.

Purpose of the Study:

• To develop and validate a computational model simulating human upper airway respiratory function.
• To investigate the effects of posture and dilator muscle activation on retro-lingual airway dimensions and airflow.

Main Methods:

• A 2D finite element model was created using CT scans of the head and neck.
• Fluid-structure interaction (FSI) was employed to simulate airflow and tissue deformation during inspiration.
• Three conditions were analyzed: standing, supine, and supine with muscle activation.

Main Results:

• The model accurately predicted changes in airway opening and airflow distribution due to posture.
• Dilator muscle activation was shown to enlarge the airway, counteracting supine-induced narrowing.
• The epiglottic region was identified as a consistently vulnerable site for obstruction, and hyoid displacement was linked to airway stability.

Conclusions:

• The developed model effectively captures the dynamic changes in the upper airway related to posture and muscle function.
• Findings highlight the epiglottic region's critical role in airway obstruction and suggest hyoid displacement as a mechanism for preventing collapse.
• This computational approach offers valuable insights for understanding obstructive sleep apnea and guiding clinical interventions.