Gore Christopher J, Bourdon Pitre C, Woolford Sarah M, Ostler Laura M, Eastwood Annette, Scroop Garry C
Department of Physiology, Australian Institute of Sport, Canberra, AUSTRALIA.
Med Sci Sports Exerc. 2006 Jun;38(6):1187-93. doi: 10.1249/01.mss.0000222848.35004.41.
A new method to estimate hemoglobin mass (Hbmass) requires capillary blood and rebreathing a carbon-monoxide (CO) bolus for 2 min. We hypothesized that incomplete circulatory mixing of CO could confound this method, so we compared capillary with venous blood to determine whether sampling site altered the percentage of carboxyhemoglobin (%HbCO) and the reliability and accuracy of the "2-min Hbmass." The conventional 20-min CO-rebreathing procedure was used as the Hbmass criterion.
In the first experiment (N=12), both fingertip capillary and antecubital venous blood were sampled 4 and 6 min after commencing 2 min of CO-rebreathing. Within 8 d, these subjects completed two 2-min and one 20-min CO-rebreathing periods. For the latter, capillary and venous blood were collected simultaneously after two 10-min periods of rebreathing. In a second experiment (N=6), both capillary and venous blood were sampled 4, 6, 8, 10, and 12 min after commencing 2 min of CO-rebreathing. A third experiment (N=6) evaluated the reliability of a modified 2-min CO-rebreathing test with capillary blood sampled at minutes 8 and 10.
Typical error (TE) for the first two 2-min tests was 1.1% (90% confidence limits 0.9-1.8%), but the average Hbmass from 2-min capillary blood was 4.8% lower than from venous blood for the 20-min procedure. In the second experiment, peak venous %HbCO occurred at minute 6, and the difference between capillary and venous values was minimal (mean+/-SD; 0.08+/-0.07, 0.01+/-0.09) at minutes 8 and 10. TE for the third experiment was 1.2% (0.8-2.5%).
A modified 2-min CO-rebreathing procedure using capillary or venous blood sampled 8 and 10 min after starting CO-rebreathing allows complete circulatory mixing and provides an accurate and reliable estimate of Hbmass.
一种估算血红蛋白质量（Hbmass）的新方法需要采集毛细血管血，并吸入一氧化碳（CO）团注2分钟。我们推测，CO的不完全循环混合可能会混淆该方法，因此我们比较了毛细血管血和静脉血，以确定采样部位是否会改变碳氧血红蛋白百分比（%HbCO）以及“2分钟Hbmass”的可靠性和准确性。传统的20分钟CO再呼吸程序用作Hbmass的标准。
在第一个实验（N = 12）中，在开始2分钟的CO再呼吸后4分钟和6分钟采集指尖毛细血管血和肘前静脉血。在8天内，这些受试者完成了两个2分钟和一个20分钟的CO再呼吸周期。对于后者，在两个10分钟的再呼吸周期后同时采集毛细血管血和静脉血。在第二个实验（N = 6）中，在开始2分钟的CO再呼吸后4、6、8、10和12分钟采集毛细血管血和静脉血。第三个实验（N = 6）评估了在第8分钟和第10分钟采集毛细血管血的改良2分钟CO再呼吸试验的可靠性。
前两个2分钟测试的典型误差（TE）为1.1%（90%置信限0.9 - 1.8%），但对于20分钟程序，2分钟毛细血管血的平均Hbmass比静脉血低4.8%。在第二个实验中，静脉血中%HbCO的峰值出现在第6分钟，在第8分钟和第10分钟时，毛细血管血和静脉血的值之间的差异最小（平均值±标准差；0.08±0.07，0.01±0.09）。第三个实验的TE为1.2%（0.8 - 2.5%）。
在开始CO再呼吸后8分钟和10分钟采集毛细血管血或静脉血的改良2分钟CO再呼吸程序可实现完全循环混合，并能准确可靠地估算Hbmass。
