Figge J, Jabor A, Kazda A, Fencl V
Department of Medicine, St. Peter's Hospital, State University of New York, Albany, USA.
Crit Care Med. 1998 Nov;26(11):1807-10. doi: 10.1097/00003246-199811000-00019.
To show how hypoalbuminemia lowers the anion gap, which can mask a significant gap acidosis; and to derive a correction factor for it.
Observational study.
Intensive care unit in a university-affiliated hospital.
Nine normal subjects and 152 critically ill patients (265 measurements).
None.
Arterial blood samples analyzed for pH, PCO2, and concentrations of plasma electrolytes and proteins. Marked hypoalbuminemia was common among the critically ill patients: 49% of them had serum albumin concentration of <20 g/L. Each g/L decrease in serum albumin caused the observed anion gap to underestimate the total concentration of gap anions by 0.25 mEq/L (r2 = .94).
The observed anion gap can be adjusted for the effect of abnormal serum albumin concentrations as follows: adjusted anion gap = observed anion gap + 0.25 x ([normal albumin] [observed albumin]), where albumin concentrations are in g/L; if given in g/dL, the factor is 2.5. This adjustment returns the anion gap to the familiar scale of values that apply when albumin concentration is normal.
展示低白蛋白血症如何降低阴离子间隙，而这可能掩盖明显的间隙性酸中毒；并推导其校正因子。
观察性研究。
大学附属医院的重症监护病房。
9名正常受试者和152名重症患者（265次测量）。
无。
分析动脉血样本的pH值、PCO2以及血浆电解质和蛋白质浓度。明显的低白蛋白血症在重症患者中很常见：其中49%的患者血清白蛋白浓度<20g/L。血清白蛋白每降低1g/L，观察到的阴离子间隙会使间隙阴离子的总浓度低估0.25mEq/L（r2 = 0.94）。
观察到的阴离子间隙可根据血清白蛋白浓度异常的影响进行如下调整：校正后的阴离子间隙 = 观察到的阴离子间隙 + 0.25×（[正常白蛋白] - [观察到的白蛋白]），其中白蛋白浓度单位为g/L；若单位为g/dL，则校正因子为2.5。这种调整使阴离子间隙恢复到白蛋白浓度正常时适用的常见数值范围。
