Change of obstruction level during drug-induced sleep endoscopy according to sedation depth in obstructive sleep apnea

Abstract

Objectives/hypothesis: We evaluated the change in upper airway collapse according to the depth of sedation during drug-induced sleep endoscopy (DISE), as well as characteristics possibly associated with that change.

Study design: Prospective, single center, observational study.

Methods: Twenty-nine patients with upper airway collapse were twice evaluated using DISE according to the depth of sedation, as confirmed by the bispectral index (BIS), which is a measure of the level of consciousness. Changes in the site and degree of obstruction according to the change in sedation depth at the retropalatal and the retroglossal levels were evaluated. The possible contributing factors of this change were explored.

Results: As DISE sedation deepened, the upper airway became narrower in 37% of patients at the retropalatal level and in 44.8% of patients at the retroglossal level. No clinical, polysomnographic, or cephalometric variables showed any association with the change in the degree of retroglossal airway narrowing, with the exception of mouth breathing during DISE.

Conclusions: The degree of upper airway narrowing can be aggravated according to the sedation depth. The monitoring of sedation depth during DISE is critical, especially in patients with mouth breathing.

Keywords: Sleep apnea; bispectral index; drug-induced sleep endoscopy; mouth breathing; nasendoscopy.