背景:目前阻塞性睡眠呼吸暂停(OSA)的标准治疗方法,持续气道正压通气(CPAP),由于各种因素,包括回路依赖的二氧化碳(CO2)再呼吸,不同的因素会加剧这种情况,如低PAP,使用自动滴定PAP或斜坡。然而,在临床实践中,再呼吸的危险因素往往被忽视或了解甚少.因此,我们的目标是评估不同PAP中常用CPAP面罩的再呼吸程度,潮气量,和呼吸频率。
方法:在一项实验室研究中,我们评估了9个面罩的再呼吸频率,该面罩通过CPAP与肺部模拟器连接,提供不同的呼吸呼吸频率(15或20次呼吸/分)和潮气量(400,500,600,700和750mL).此外,建立了一个理论模型来描述在各种呼吸设置下,四种不同面罩再呼吸CO2的可能性.
结果:总体而言,在以低PAP为特征的情况下,所有面罩的性能较差,潮气量大,和高呼吸率。然而,梦幻服装,细微差别,午睡,Vitera,尤其是V2面罩表现出更大的再呼吸敏感性,与F20,P10,Brevida,和里约口罩,用于相同的PAP或通气参数变化。数学模型表明里约再呼吸的风险,对于10次呼吸/分钟或以下的呼吸频率,P10和Nuance面罩可以忽略不计。
结论:循环依赖的CO2再呼吸可能是常见的情况,需要在开始CPAP治疗时仔细选择面罩以获得最佳临床结果。
BACKGROUND: The current standard treatment for obstructive sleep apnea (OSA), continuous positive airway pressure (CPAP), is characterized by a low adherence rate due to various factors including circuit-dependent carbon dioxide (CO2) rebreathing, which can exacerbated by disparate factors, such as low PAP, use of auto-titrating PAP or ramps. However, risk factors for rebreathing are often overlooked or poorly understood in clinical practice. Therefore, our objective was to evaluate the extent of rebreathing occurring with commonly used CPAP masks across varying PAPs, tidal volumes, and respiratory rates.
METHODS: In a bench study, we assessed the rebreathing rate of nine masks interfacing a CPAP with a lung simulator providing different breathing respiratory rates (15 or 20 breaths/min) and tidal volumes (400, 500, 600, 700 and 750 mL). Additionally, a theoretical model was developed to describe the likelihood of CO2 rebreathing from four different masks at various breathing settings.
RESULTS: Overall, all masks performed worse in situations characterized by low PAPs, high tidal volumes, and high respiratory rates. However, Dreamwear, Nuance, Siesta, Vitera, and particularly V2 masks exhibited greater susceptibility to rebreathing compared to F20, P10, Brevida, and Rio masks for the same variations of PAPs or ventilatory parameters. The mathematical model suggested that the risk of rebreathing for Rio, P10 and Nuance mask is negligible for respiratory rates of 10 breaths/min or below.
CONCLUSIONS: Circuit-dependent CO2 rebreathing can be a common occurrence and warrants careful mask selection upon CPAP therapy initiation for optimal clinical outcomes.