Lucas Brian P, D'Addio Antonietta, Clark Jennifer, Block Clay, Manning Harold, Remillard Brian, Leiter J C
Medicine Service, White River Junction VA Medical Center, 215 North Main Street, White River Junction, VT.
Geisel School of Medicine at Dartmouth College, Hanover, NH.
J Clin Ultrasound. 2017 Oct;45(8):488-496. doi: 10.1002/jcu.22491. Epub 2017 May 8.
Central vein point-of-care ultrasonography must be reproducible to detect intravascular volume changes. We sought to determine which measurement step, image acquisition or interpretation, could be more compromising for reproducibility.
Three investigators each acquired inferior vena cava (IVC) and internal jugular (IJV) vein ultrasonographic sequences (US) from a convenience sample of 21 hospitalized general medicine participants and then interpreted each US three separate times. We partitioned the random errors of acquisition and interpretation, attributing wider dispersions of each to larger reductions in reproducibility.
We analyzed 351 interpretations of 39 IVC and 432 interpretations of 48 IJV US. Reproducibility of the maximum (standard error of measurement 3.3 mm [95% confidence interval, CI 2.7-4.2 mm]) and minimum (4.8 mm [3.9-6.3 mm]) IVC diameter measurements were worse than that of the mediolateral (2.5 mm [2.0-3.2 mm]) and anteroposterior (2.5 mm [2.0-3.1 mm]) IJV diameters. The dispersions of random measurement errors were wider among acquisitions than interpretations.
Among our investigators, central vein diameter measurements obtained by point-of-care ultrasonography are not sufficiently reproducible to distinguish clinically meaningful intravascular volume changes from measurement errors. Reproducibility could be most effectively improved by reducing the random measurement errors of acquisition. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:488-496, 2017.
中心静脉即时超声检查必须具有可重复性，以检测血管内容量变化。我们试图确定哪个测量步骤，即图像采集还是解读，对可重复性的影响更大。
三名研究人员分别从21名住院普通内科参与者的便利样本中获取下腔静脉（IVC）和颈内静脉（IJV）的超声序列（US），然后对每个US进行三次独立解读。我们划分了采集和解读的随机误差，将每个误差的更广泛离散归因于可重复性的更大降低。
我们分析了39个IVC US的351次解读和48个IJV US的432次解读。IVC最大直径（测量标准误差3.3毫米[95%置信区间，CI 2.7 - 4.2毫米]）和最小直径（4.8毫米[3.9 - 6.3毫米]）测量的可重复性比IJV的中外径（2.5毫米[2.0 - 3.2毫米]）和前后径（2.5毫米[2.0 - 3.1毫米]）更差。随机测量误差的离散在采集之间比在解读之间更广泛。
在我们的研究人员中，即时超声检查获得的中心静脉直径测量的可重复性不足以将临床上有意义的血管内容量变化与测量误差区分开来。通过减少采集的随机测量误差可以最有效地提高可重复性。© 2017威利期刊公司。《临床超声杂志》45:488 - 496，2017。
