1350 Masking the Challenge: Evaluating Nasal vs. Oronasal Approaches in OSA Treatment

Abstract Introduction Obstructive Sleep Apnea (OSA) is a prevalent condition characterized by recurrent upper airway obstruction during sleep. Traditional Positive Airway Pressure (PAP) therapy is not effective for all patients, highlighting the need for alternative treatment strategies. This case series investigates the efficacy of nasal versus oronasal masks in mitigating airway obstruction during Drug-Induced Sleep Endoscopy (DISE). Report of case(s) We evaluated ten patients who had experienced failure with PAP therapy and were undergoing DISE to explore alternative treatment options for OSA. During DISE, we applied the previously prescribed PAP pressures using both oronasal and nasal masks. Additionally, we administered oxymetazoline to assess its effect on nasal passage patency. Airway obstruction was assessed using the Velum, Oropharynx, Tongue and Epiglottis (VOTE) classification system. The depth of sedation with propofol was tracked using the Bispectral Index (BIS). The masks were applied gently without strapping to minimize their impact on airway collapse. Our findings indicated that nasal masks were more effective than oronasal masks in relieving obstruction at the levels of the oropharynx and tongue base under therapeutic pressures. Notably, all patients were not mouth breathers, making chin lifts or chin straps unnecessary. Both the nasal and oronasal masks resulted in comparable expansion of the velum; however, the nasal masks demonstrated a significant improvement in the opening of the hypopharynx and the base of the tongue, effectively alleviating collapse in these areas. In contrast, even when unstrapped, the oronasal mask led to a notable worsening of collapse at the base of the tongue, often nearly completely obstructing the airway. No significant difference was observed in nasal passage patency with oxymetazoline. Conclusion CPAP delivered via nasal masks demonstrated superior efficacy over oronasal masks in alleviating airway obstruction in patients with OSA when observed under DISE conditions, particularly at the level of hypopharynx and base of the tongue. This potential for worsened upper airway collapse may be a contributor to many patients’ complaints of feeling claustrophobic with the full-face masks and should be taken seriously in the choice of PAP interface. Our findings support the need for tailored treatment approaches to enhance outcomes for patients with OSA. Support (if any)