Department of Physiology, Biomedical Discovery Institute, Monash University, Melbourne, VIC, Australia.
School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, QLD, Australia.
Chest. 2023 Sep;164(3):747-756. doi: 10.1016/j.chest.2023.03.025. Epub 2023 Mar 27.
CPAP delivered via an oronasal mask is associated with lower adherence, higher residual apnea-hypopnea index (AHI), and increased CPAP therapeutic pressure compared with nasal masks. However, the mechanisms underlying the increased pressure requirements are not well understood.
How do oronasal masks affect upper airway anatomy and collapsibility?
Fourteen patients with OSA underwent a sleep study with both a nasal and oronasal mask, each for one-half of the night (order randomized). CPAP was manually titrated to determine therapeutic pressure. Upper airway collapsibility was assessed using the pharyngeal critical closing pressure (P) technique. Cine MRI was done to dynamically assess the cross-sectional area of the retroglossal and retropalatal airway throughout the respiratory cycle with each mask interface. Scans were repeated at 4 cm HO and at the nasal and oronasal therapeutic pressures.
The oronasal mask was associated with higher therapeutic pressure requirements (ΔM ± SEM; +2.6 ± 0.5; P < .001) and higher P (+2.4 ± 0.5 cm HO; P = .001) compared with the nasal mask. The change in therapeutic pressure between masks was strongly correlated with the change in P (r = 0.73; P = .003). Increasing CPAP increased both the retroglossal and retropalatal airway dimensions across both masks. After controlling for pressure and breath phase, the retropalatal cross-sectional area was moderately larger when using a nasal vs an oronasal mask (+17.2 mm; 95% CI, 6.2-28.2, P < .001) while nasal breathing.
Oronasal masks are associated with a more collapsible airway than nasal masks, which likely contributes to the need for a higher therapeutic pressure.
与鼻罩相比，经口鼻面罩输送的 CPAP 与较低的依从性、较高的残余呼吸暂停低通气指数（AHI）和更高的 CPAP 治疗压力相关。然而，导致压力需求增加的机制尚不清楚。
口鼻面罩如何影响上气道解剖结构和塌陷性？
14 例 OSA 患者进行了一项睡眠研究，分别使用鼻罩和口鼻面罩各半晚（随机顺序）。手动滴定 CPAP 以确定治疗压力。使用咽腔临界关闭压力（P）技术评估上气道塌陷性。使用电影 MRI 动态评估每个面罩接口在整个呼吸周期中舌后和腭后气道的横截面积。在 4cmH2O 及鼻罩和口鼻罩治疗压力下重复扫描。
与鼻罩相比，口鼻面罩与更高的治疗压力需求（ΔM±SEM；+2.6±0.5；P<0.001）和更高的 P（+2.4±0.5cmHO；P=0.001）相关。面罩间治疗压力的变化与 P 的变化密切相关（r=0.73；P=0.003）。增加 CPAP 可增加两种面罩的舌后和腭后气道尺寸。在控制压力和呼吸相位后，使用鼻罩时，与使用口鼻面罩相比，腭后气道横截面积更大（+17.2mm；95%CI，6.2-28.2，P<0.001）。
与鼻罩相比，口鼻面罩与更易塌陷的气道相关，这可能是需要更高治疗压力的原因。
