ABSTRACT
OBJECTIVE: Obstructive sleep apnea (OSA) is a prevalent disorder, with oral breathing influencing its severity. Expiratory velopharyngeal obstruction (EVO), observed during drug-induced sleep endoscopy (DISE), may contribute to oral breathing in OSA patients. EVO results in obstruction between the pharynx and nasal cavity during expiration. This study aims to identify factors associated with positive EVO during DISE. STUDY DESIGN: Case series. SETTING: Tertiary Medical Center. METHODS: Seventy-two OSA patients underwent clinical evaluation, polysomnography, and DISE, utilizing interventions like intraoral negative airway pressure (iNAP), mouth closure, and oral appliances (OAs) in supine positions with head rotation. The findings, classified under velopharynx, oropharynx, tongue base, epiglottis, included the presence of EVO. RESULTS: The results demonstrated that interventions including mouth closure and iNAP were associated with increased observation of EVO (43.1% and 34.7%) compared to OA (20.1%). However, head rotation was associated with decreased presence of EVO during DISE compare to supine (26% vs 35.8%). Noticeably, per 1 year increase of age was associated with an increased odds of EVO (odds ratio: 1.03, 95% confidence interval: 1.01-1.06). However, no other baseline characteristics were significantly associated the odds of EVO. CONCLUSION: Our study reveals the effectiveness of head rotation and OA in reducing EVO and improving mouth breathing in OSA patients, offering valuable insights for future treatment strategies.
