Marshall S Gregory, Henry Nicholas R, Russian Christopher J
Department of Respiratory Care, Texas State University, San Marcos, Texas.
Respir Care. 2016 Apr;61(4):397-404. doi: 10.4187/respcare.04169. Epub 2015 Nov 17.
Nasal cycling may present negative consequences for oxygen-dependent patients using a nasal cannula. This study investigates the effects of nasal cycling on the delivered F(IO2) via nasal cannula in an anatomic model following a baseline study comparing right and left prong nasal cannula oxygen flow delivery.
Flow from right and left nasal cannula prongs were measured simultaneously using thermal mass flow meters while delivering 0.5-6-L/min oxygen for 5 nasal cannulas from different manufacturers. An adult mannikin head with an anatomically correct upper airway was connected to a QuickLung Breather test lung. Nasal cannula-delivered F(IO2) was recorded using a polarographic oxygen analyzer with naris occlusion simulated by inserting a 5.0 endotracheal tube into the naris and inflating the endotracheal tube cuff. Data were recorded with both nares open, for right naris occluded and left naris patent, and for left naris occluded and right naris patent at 0.5-6 L/min.
A paired t test demonstrated statistical differences between right and left nasal cannula prong oxygen flows (P < .01). Multivariate analysis of variance demonstrated no significant differences in nasal cannula prong flow between nasal cannula manufacturers. Repeated measures analysis of variance demonstrated significant differences for measured inspired F(IO2) (P < .01) when alternating nares were occluded and patent. The Bonferroni post hoc test showed significant differences for measured F(IO2) between patent nares and right naris patent-left naris occluded (P < .01) and between patent nares and left naris patent-right naris occluded (P < .01). Measured F(IO2) decreased by as much as 0.1 when one naris was occluded.
Oxygen delivery by nasal cannula may be inefficient in the presence of the nasal cycle. Delivered nasal cannula oxygen concentrations decreased when bilateral nasal patency changed to unilateral nasal patency. Although statistically different, nasal cannula prong oxygen flow may not be clinically important across the full range of flows.
对于使用鼻导管的依赖氧气的患者而言，鼻周期可能会产生不良后果。在一项比较左右鼻导管吸氧流量的基线研究之后，本研究在解剖模型中探究了鼻周期对通过鼻导管输送的吸入氧分数（F(IO2)）的影响。
使用热式质量流量计同时测量来自不同制造商的5种鼻导管左右两个管头的流量，同时输送0.5 - 6升/分钟的氧气。一个具有解剖学上正确上呼吸道的成年人体模型头部连接到QuickLung Breather测试肺。通过将一根5.0的气管插管插入鼻孔并充盈气管插管的气囊来模拟鼻孔阻塞，使用极谱式氧分析仪记录鼻导管输送的F(IO2)。在两个鼻孔均开放、右鼻孔阻塞左鼻孔通畅以及左鼻孔阻塞右鼻孔通畅的情况下，以0.5 - 6升/分钟的流量记录数据。
配对t检验显示左右鼻导管管头的氧气流量存在统计学差异（P < 0.01）。多因素方差分析表明不同制造商的鼻导管管头流量无显著差异。重复测量方差分析表明，当交替的鼻孔阻塞和通畅时，测量的吸入F(IO2)存在显著差异（P < 0.01）。Bonferroni事后检验显示，通畅鼻孔与右鼻孔通畅 - 左鼻孔阻塞时测量的F(IO2)之间存在显著差异（P < 0.01），以及通畅鼻孔与左鼻孔通畅 - 右鼻孔阻塞时测量的F(IO2)之间存在显著差异（P < 0.01）。当一个鼻孔阻塞时，测量的F(IO2)下降多达0.1。
在存在鼻周期的情况下，通过鼻导管输送氧气可能效率低下。当双侧鼻腔通畅变为单侧鼻腔通畅时，鼻导管输送的氧气浓度会降低。尽管在统计学上存在差异，但在整个流量范围内，鼻导管管头的氧气流量可能在临床上并不重要。
