Impact of Upper Airway Sensory Dysfunction on Respiratory Events during Sleep in Patients with Obstructive Sleep Apnea

Abstract

Objective: To assess the influence of upper airway sensory dysfunction on the respiratory events during sleep in patients with obstructive sleep apnea syndrome (OSAS). Methods: Our study was performed over 30 patients with OSAS. The patients underwent a second night polisomnography (PSG) after bupivacaine application to uvula and soft palate and the outcomes of both PSG results were compared. Results: In PSG-2, the mean Apnea-hypopnea index (AHI), AHI-supine, AHI-right lateral, AHI-REM and AHI-nonREM values were significantly higher than the same data acquired in PSG-1 (p<0.001, p=0.001, p<0.001, p<0.001, and p=0.001, respectively). In PSG-2, mean and minimum arterial O2 saturation were significantly lower compared to PSG-1 (p=0.021 and p=0.039, respectively). The correlation analysis of PSG-2 showed that AHI-nonREM and AHI-supine are more effected from the sensorial blockade. Conclusion: Our study showed that, when the protective neuromuscular mechanism is removed by upper airway sensory blockage, the severity of OSAS increases. Upper airway sensorial blockade more influentially effects respiratory events in supine position and in non-REM phase.