Department of Medical Life Science, Faculty of Medical Bioscience, Kyushu University of Health and Welfare, Nobeoka, Japan; Department of Clinical Laboratory Sciences, Faculty of Health Sciences, Yamaguchi University Graduate School of Medicine, Ube, Japan.
Department of Clinical Laboratory Sciences, Faculty of Health Sciences, Yamaguchi University Graduate School of Medicine, Ube, Japan.
Clin Chim Acta. 2017 Sep;472:131-135. doi: 10.1016/j.cca.2017.07.022. Epub 2017 Jul 19.
We investigated postural effects on concentrations of commonly measured serum analytes and sought for optimal duration of sitting before venipuncture in an outpatient setting.
Seven healthy volunteers changed posture serially at 30-minute (min) intervals from lying, sitting, slowly walking, sitting, and to lying again. At the end of the first lying posture, wing-needle was inserted into cubital vein and 3mL of blood was drawn every 5min. All the serum was stored at -80°C until the time of collective measurements for 16 major chemistry analytes two weeks later.
Concentrations of macromolecular analytes (albumin, total cholesterol, alkaline phosphatase, etc.) in supine position were increased (on average 5-7%) after 30min of sitting and further increased (10-14%) during 30min of walking. After slow walking, time required for return of values to the levels of sitting posture took approximately 20min. Concentrations of small molecules (sodium, urea, etc.) did not show any variation by the postural changes. Potassium and inorganic phosphate showed walking-related increase in concentrations. Creatinine was lowered in sitting posture, which implicates postural changes in renal flow.
It is generally recommended to sit for 20min or more before venipuncture, although the effect of prior physical movement remains a little longer for potassium and inorganic phosphate.
我们研究了体位对常见血清分析物浓度的影响，并在门诊环境中寻找最佳的静脉穿刺前静坐时间。
7 名健康志愿者每隔 30 分钟（min）连续改变体位，从卧位、坐位、缓慢行走、坐位到再次卧位。在第一次卧位结束时，将翼状针插入肘静脉，每隔 5 分钟抽取 3mL 血液。所有血清均在-80°C 下储存，两周后再进行 16 项主要化学分析物的集体测量。
大分子分析物（白蛋白、总胆固醇、碱性磷酸酶等）在仰卧位时，坐 30 分钟后浓度升高（平均升高 5-7%），行走 30 分钟后进一步升高（升高 10-14%）。缓慢行走后，恢复到坐姿所需的时间约为 20 分钟。小分子（钠、尿素等）浓度不受体位变化的影响。钾和无机磷的浓度随着行走而增加。肌酐在坐姿时降低，这表明肾血流量的变化。
一般建议在静脉穿刺前静坐 20 分钟或更长时间，尽管钾和无机磷的体位变化影响仍会持续更长时间。
