Hansen Rasmus Søgaard, Revsholm Jesper, Sandberg Maria B, Jørgensen Louise H, Nybo Mads
Department of Clinical Biochemistry, Odense University Hospital, Odense C, Denmark.
Ann Clin Biochem. 2023 May;60(3):155-159. doi: 10.1177/00045632231152082. Epub 2023 Feb 7.
Studies comparing venous total carbon dioxide (tCO) and standard hydrogen carbonate (HCO(P,st)) has shown diverse results, and it is debatable whether these two parameters can be used interchangeably for workup of acid-base disorders in a hospital setting.
All patients with an HCO(P,st) requisition from any department at Odense University Hospital between 11th May 2021 and 1st June 2021 had tCO and HCO(P,st) analysed simultaneously. TCO was measured on Cobas® 8000, c702 module, while HCO(P,st) was calculated based on measurements on ABL835 Flex.
From 1210 patients, mean (standard deviation (SD)) was 22.9 (3.7) mmol/L for tCO and 22.5 (2.9) mmol/L for HCO(P,st). TCO range was 10.1-42.3 mmol/L and 11.7-41.4 mmol/L for HCO(P,st). Linear regression showed that tCO (mmol/L) = -2.90 + 1.15 × HCO(P,st) (mmol/L) with = 0.81. Bias (mean (SD) difference) between tCO and HCO(P,st)) was 0.4 (1.7) mmol/L with a -5.0-9.6 mmol/L range. Limits of agreement was -2.90-3.70 mmol/L. Comparison of classification within, above or below reference interval for tCO and HCO(P,st) showed that 984 samples (81%) retained their classification. Only one sample (0.1%) would be severely misclassified (outside the respective reference intervals) if HCO(P,st) was considered the gold standard. Of the samples investigated, 46.1% had a mean difference between tCO and HCO(P,st) of 0-1 mmol/L and 30.3% had 1.1-2.0 mmol/L.
Our results indicate that venous tCO and venous HCO(P,st) can be used interchangeably in a hospital setting for workup of acid-base disorders.
比较静脉血总二氧化碳（tCO）和标准碳酸氢盐（HCO(P,st)）的研究结果各异，在医院环境中，这两个参数是否可互换用于酸碱紊乱的检查仍存在争议。
对2021年5月11日至2021年6月1日期间奥登塞大学医院各科室所有申请检测HCO(P,st)的患者同时进行tCO和HCO(P,st)分析。tCO在Cobas® 8000、c702模块上测量，而HCO(P,st)则根据ABL835 Flex上的测量值计算得出。
在1210例患者中，tCO的均值（标准差（SD））为22.9（3.7）mmol/L，HCO(P,st)为22.5（2.9）mmol/L。tCO范围为10.1 - 42.3 mmol/L，HCO(P,st)范围为11.7 - 41.4 mmol/L。线性回归显示tCO（mmol/L） = -2.90 + 1.15×HCO(P,st)（mmol/L），相关系数为0.81。tCO与HCO(P,st)之间的偏差（均值（SD）差异）为0.4（1.7）mmol/L，范围为 - 5.0 - 9.6 mmol/L。一致性界限为 - 2.90 - 3.70 mmol/L。比较tCO和HCO(P,st)在参考区间内、之上或之下的分类情况表明，984个样本（81%）保持了其分类。如果将HCO(P,st)视为金标准，只有一个样本（0.1%）会被严重误分类（超出各自的参考区间）。在研究的样本中，46.1%的tCO与HCO(P,st)均值差异为0 - 1 mmol/L，30.3%的差异为1.1 - 2.0 mmol/L。
我们的结果表明，在医院环境中，静脉血tCO和静脉血HCO(P,st)可互换用于酸碱紊乱的检查。
