Computational fluid dynamics of upper airway aerodynamics for exercise‐induced laryngeal obstruction: A feasibility study

Abstract

ObjectiveUse of computational fluid dynamic (CFD) simulations to measure the changes in upper airway geometry and aerodynamics during (a) an episode of Exercise‐Induced Laryngeal Obstruction (EILO) and (b) speech therapy exercises commonly employed for patients with EILO.MethodsMagnetic resonance imaging stills of the upper airway including the nasal and oral cavities from an adult female were used to re‐construct three‐dimensional geometries of the upper airway. The CFD simulations were used to compute the maximum volume flow rate (l/s), pressure (Pa), airflow velocity (m/s) and area of cross‐section opening in eight planes along the vocal tract, separately for inhalation and exhalation.ResultsNumerical predictions from three‐dimensional geometrical modeling of the upper airway suggest that the technique of nose breathing for inhalation and pursed lip breathing for exhalation show most promising pressure conditions and cross‐sectional diameters for rescue breathing exercises. Also, if EILO is due to the constriction at the vocal fold level, then a quick sniff may also be a proper rescue inhalation exercise. EILO affects both the inspiratory and the expiratory phases of breathing.ConclusionsA prior knowledge of the supraglottal aerodynamics and the corresponding upper airway geometry from CFD analysis has the potential to assist the clinician in choosing the most effective rescue breathing technique for optimal functional outcome of speech therapy intervention in patients with EILO and in understanding the pathophysiology of EILO on a case‐by‐case basis with future studies.Level of Evidence4

Exercise-induced Laryngeal Obstruction

“…Medializace supraglotických struktur zmenší průměr laryngeálního vchodu pod kritickou úroveň pro laminární proudění vzduchu při nádechu, což způsobí nárůst negativního tlaku pod nimi, tedy v hlasivkové štěrbině, a tím dojde k sekundární addukci hlasivek. Při jakém průtoku se tomu tak stane, je dáno rozměry a konfigurací laryngeálního vchodu, pevností vlastních struktur hrtanu a podporou okolních struktur (Döllinger et al, 2023;Hull et al, 2020;Røksund et al, 2017).…”