Royal Joshua T, Fisher Jason T, Mlinar Tinkara, Mekjavic Igor B, McDonnell Adam C
Department of Automation, Biocybernetics, and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia.
Jozef Stefan International Postgraduate School, Ljubljana, Slovenia.
Front Physiol. 2022 Nov 24;13:1021588. doi: 10.3389/fphys.2022.1021588. eCollection 2022.
Haemoglobin mass (Hbmass) assessment with the carbon monoxide rebreathing method is a more accurate estimate than other measures of oxygen-carrying capacity. Blood may be collected by several means and differences in the measured variables may exist as a result. The present study assessed the validity and reliability of calculated Hbmass and intravascular volumes obtained from capillary blood (CAP) when compared to venous blood (VEN) draws. Twenty-two adults performed a carbon monoxide rebreathing procedure with paired VEN and CAP draws at baseline, pre-rebreathing and post-rebreathing (POST). Thirteen of these participants performed this protocol on two occasions to assess the data reliability from both blood sampling sites. In a second experiment, 14 adults performed a 20-min seated and a 20-min supine rest to assess for the effect of posture on haematological parameters. Haemoglobin mass (CAP = 948.8 ± 156.8 g; VEN = 943.4 ± 157.3 g, = 0.108) and intravascular volume (CAP = 6.5 ± 1 L; VEN = 6.5 ± 0.9 L, = 0.752) were statistically indifferent, had low bias (Hbmass bias = 14.45 ± 40.42 g, LoA -64.78 g-93.67 g) and were highly correlated between sampling techniques. Reliability analysis demonstrated no difference in the mean change in variables calculated from both sampling sites and good to excellent intraclass correlation coefficients (>0.700), however, typical measurement error was larger in variables measured using CAP (VEN Hbmass TE% = 2.1%, CAP Hbmass TE% = 5.5%). The results indicate that a supine rest prior to the rebreathing protocol would have a significant effect on haemoglobin concentration and haematocrit values compared to a seated rest, with no effect on carboxyhaemoglobin %. The present study demonstrates that CAP and VEN were comparable for the calculation of Hbmass and intravascular volumes in terms of accuracy. However, reduced reliability and increased error in the CAP variables indicates that there are methodological considerations to address when deciding which blood drawing technique to utilise. To reduce this CAP error, increased replicate analyses are required.
与其他氧携带能力测量方法相比，采用一氧化碳重呼吸法评估血红蛋白总量（Hbmass）更为准确。血液可通过多种方式采集，这可能导致测量变量存在差异。本研究评估了与静脉血（VEN）采集相比，从毛细血管血（CAP）获得的计算Hbmass和血管内容积的有效性和可靠性。22名成年人在基线、重呼吸前和重呼吸后（POST）进行了一氧化碳重呼吸程序，同时采集配对的VEN和CAP血样。其中13名参与者分两次执行该方案，以评估两个采血部位数据的可靠性。在第二个实验中，14名成年人进行了20分钟的坐姿休息和20分钟的仰卧休息，以评估姿势对血液学参数的影响。血红蛋白总量（CAP = 948.8±156.8 g；VEN = 943.4±157.3 g，P = 0.108）和血管内容积（CAP = 6.5±1 L；VEN = 6.5±0.9 L，P = 0.752）在统计学上无差异，偏差较低（Hbmass偏差 = 14.45±40.42 g，一致性界限为-64.78 g至93.67 g），且两种采样技术之间高度相关。可靠性分析表明，两个采样部位计算的变量平均变化无差异，组内相关系数良好至优秀（>0.700），然而，使用CAP测量的变量的典型测量误差更大（VEN血红蛋白总量TE% = 2.1%，CAP血红蛋白总量TE% = 5.5%）。结果表明，与坐姿休息相比，重呼吸方案前的仰卧休息对血红蛋白浓度和血细胞比容值有显著影响，对碳氧血红蛋白%无影响。本研究表明，就准确性而言，CAP和VEN在计算Hbmass和血管内容积方面具有可比性。然而，CAP变量的可靠性降低和误差增加表明，在决定使用哪种采血技术时，需要考虑方法学问题。为减少这种CAP误差，需要增加重复分析。
