White David E, Bartley Jim, Shakeel Muhammad, Nates Roy J, Hankin Robin K S
School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand.
Department of Otolaryngology - Head and Neck Surgery, Counties District Health Board, Manukau, Auckland, New Zealand; Department of Surgery, University of Auckland, Auckland, New Zealand.
J Biomech. 2016 Jun 14;49(9):1887-1890. doi: 10.1016/j.jbiomech.2016.04.034. Epub 2016 May 3.
The nasal cycle, through variation in nasal airflow partitioning, allows the upper airway to accommodate the contrasting demands of air conditioning and removal of entrapped air contaminants. The purpose of this study was to investigate the influence of nasal continuous positive airway pressure (nCPAP) breathing has on both nasal airflow partitioning and nasal geometry. Using a custom-made nasal mask, twenty healthy participants had the airflow in each naris measured during normal nasal breathing followed by nCPAP breathing. Eight participants also underwent magnetic resonance imaging (MRI) of the nasal region during spontaneous nasal breathing, and then nCPAP breathing over a range of air pressures. During nCPAP breathing, a simultaneous reduction in airflow through the patent airway together with a corresponding increase in airway flow within the congested nasal airway were observed in sixteen of the twenty participants. Nasal airflow resistance is inversely proportional to airway cross-sectional area. MRI data analysis during nCPAP breathing confirmed airway cross-sectional area reduced along the patent airway while the congested airway experienced an increase in this parameter. During awake breathing, nCPAP disturbs the normal inter-nasal airflow partitioning. This could partially explain the adverse nasal drying symptoms frequently reported by many users of this therapy.
鼻周期通过鼻气流分配的变化，使上呼吸道能够适应空气调节和清除截留的空气污染物这两种截然不同的需求。本研究的目的是调查鼻持续气道正压通气（nCPAP）呼吸对鼻气流分配和鼻腔几何形态的影响。使用定制的鼻面罩，20名健康参与者在正常鼻呼吸和nCPAP呼吸期间测量每个鼻孔的气流。8名参与者还在自主鼻呼吸期间接受了鼻腔区域的磁共振成像（MRI），然后在一系列气压下进行nCPAP呼吸。在nCPAP呼吸期间，20名参与者中有16名观察到通过通畅气道的气流同时减少，而在阻塞的鼻气道内气道流量相应增加。鼻气流阻力与气道横截面积成反比。nCPAP呼吸期间的MRI数据分析证实，通畅气道的气道横截面积减小，而阻塞气道的该参数增加。在清醒呼吸期间，nCPAP会扰乱正常的鼻间气流分配。这可以部分解释许多该疗法使用者经常报告的不良鼻干燥症状。
