Department of General Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, 113-8510, Japan.
Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, The Warren Alpert Medical School of Brown University, Providence, RI, 02903, USA.
Lung. 2024 Feb;202(1):83-90. doi: 10.1007/s00408-023-00662-2. Epub 2023 Nov 29.
Measurements of diaphragm function by ultrasonography are affected by body position, but reference values in the seated position have not been established for an Asian population. This study aimed to determine reference values for diaphragm thickness, thickening fraction, and dome excursion by ultrasonography and to investigate the effects of sex, height, and body mass index.
Diaphragm ultrasonography was performed on 109 seated Japanese volunteers with normal respiratory function who were enrolled between March 2022 and January 2023. Thickness, thickening fraction, and excursion were measured. Reference values and the measurement success rate were calculated. Multivariate analysis adjusted for sex, height, and body mass index was performed.
The measurement success rate was better for thickness than for excursion. The mean (lower limit of normal) values on the right/left sides were as follows. During quiet breathing, thickness at end expiration(mm) was 1.7 (0.9)/1.6 (0.80), thickening fraction(%) was 50 (0.0)/52 (0.0), and excursion(cm) was 1.7 (0.5)/1.9 (0.5). During deep breathing, the thickening fraction was 111 (24)/107 (22), and the excursion was 4.4 (1.7)/4.1 (2.0). In multivariate analysis, body mass index was positively associated with thickness but not with the thickening fraction.
The reference values in this study were smaller than those in previous reports from Europe. Considering that thickness is influenced by body mass index, using Western reference values in Asia, where the average body mass index is lower, might not be appropriate. The thickening fraction in deep breathing is unaffected by other items and can be used more universally.
超声测量膈肌功能受体位影响，但尚未建立亚洲人群坐位时的参考值。本研究旨在确定超声测量膈肌厚度、增厚分数和穹顶位移的参考值，并探讨性别、身高和体重指数的影响。
2022 年 3 月至 2023 年 1 月期间，对 109 名呼吸功能正常的日本坐位志愿者进行膈肌超声检查。测量厚度、增厚分数和位移。计算参考值和测量成功率。对性别、身高和体重指数进行多元分析调整。
厚度的测量成功率优于位移。右侧/左侧的平均值（正常下限）如下。在静息呼吸时，呼气末厚度（mm）为 1.7（0.9）/1.6（0.80），增厚分数（%）为 50（0.0）/52（0.0），位移（cm）为 1.7（0.5）/1.9（0.5）。在深呼吸时，增厚分数为 111（24）/107（22），位移为 4.4（1.7）/4.1（2.0）。多元分析显示，体重指数与厚度呈正相关，与增厚分数无关。
本研究中的参考值小于欧洲以前报告的参考值。考虑到厚度受体重指数影响，在亚洲使用平均体重指数较低的西方参考值可能并不合适。深呼吸时的增厚分数不受其他因素影响，可更广泛地使用。
