Institute of Respiratory Monitoring and Support, Shandong University, Jinan, China.
Biomedical Engineering Institute, School of Control Science and Engineering, Shandong University, Jinan, China.
Clin Respir J. 2022 Feb;16(2):123-129. doi: 10.1111/crj.13459. Epub 2021 Dec 6.
From the point of view of machine construction and hydrodynamics, this paper innovatively proposes that the essence of high-flow nasal cannula (HFNC) is a constant-flow mode in noninvasive ventilator (NIVCFM). This study enrolled healthy adults as study subjects to assess the subjective comfort assessed by visual analog scoring scale of NIVCFM/HFNC and objective comfort measured by the noise level generated by NIVCFM/HFNC, aiming to provide a scientific basis for the rational clinical application of NIVCFM/HFNC.
Forty-four healthy adults participated in this study. The noise generated by NIVCFM/HFNC is measured, and the comfort is evaluated during NIVCFM delivery at flow rates of 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, and 60 L/min.
When the ventilator flow rate is 60 L/min, the maximum noise is 65.9 dB, increasing noise by 23.7 dB from a baseline of 42.2 dB at the flow rate of 0 L/min. There was a strong nonlinear positive correlation between the noise level and the flow rates. The median score for dry mouth, nose or throat, dysphagia, sore throat, and other discomfort was 0. The median score for dyspnea was 0 at 0-30 L/min, 1 at 35-55 L/min, and 2 at 60 L/min.
The grater the flow rate, the greater the noise generated by NIVCFM/HFNC (<65.9 dB). The maximum flow rate that most healthy adults can able to tolerate is 30 L/min, and the main discomfort is dyspnea.
从机器结构和流体力学的角度来看，本文创新性地提出高流量鼻导管（HFNC）的本质是无创通气（NIVCFM）中的恒流模式。本研究纳入健康成年人作为研究对象，通过视觉模拟评分量表评估 NIVCFM/HFNC 的主观舒适度和 NIVCFM/HFNC 产生的噪声水平来衡量的客观舒适度，旨在为 NIVCFM/HFNC 的合理临床应用提供科学依据。
共有 44 名健康成年人参与了这项研究。在 0、5、10、15、20、25、30、35、40、45、50、55 和 60 L/min 的流速下，测量 NIVCFM/HFNC 产生的噪声，并评估 NIVCFM 输送时的舒适度。
当呼吸机流量为 60 L/min 时，最大噪声为 65.9 dB，与流量为 0 L/min 时的 42.2 dB 基线相比，噪声增加了 23.7 dB。噪声水平与流速之间存在强烈的非线性正相关。口干、鼻或咽喉、吞咽困难、喉咙痛和其他不适的中位数评分为 0。0-30 L/min 时，呼吸困难的中位数评分为 0，35-55 L/min 时为 1，60 L/min 时为 2。
流速越大，NIVCFM/HFNC 产生的噪声越大（<65.9 dB）。大多数健康成年人能够耐受的最大流速为 30 L/min，主要不适为呼吸困难。
