体内和体外镁离子和钙离子的关系。

In vivo and in vitro relationship between ionized magnesium and ionized calcium.

机构信息

Central Diagnostic Laboratory, University Medical Center Utrecht and University Utrecht, Utrecht, the Netherlands.

出版信息

Clin Biochem. 2024 Dec;133-134:110815. doi: 10.1016/j.clinbiochem.2024.110815. Epub 2024 Sep 4.

DOI:10.1016/j.clinbiochem.2024.110815

PMID:39241903

Abstract

OBJECTIVES

The objective of this study was to determine the in vivo correlation of ionized magnesium (iMg) with ionized calcium (iCa), total calcium, albumin and pH. In addition, the analytical interference of iCa on iMg measurement on the Stat Profile Prime Plus (Nova Biomedical) and vice versa was defined.

METHODS

In vivo correlation of iCa, iMg and pH was studied in 238 paired blood gas samples of 109 different patients admitted to the intensive care unit. Albumin and total magnesium (tMg) were measured in heparinized plasma samples. Measurement of iMg was performed with the ion selective magnesium electrode (ISE) of the Stat Profile Prime Plus (Nova Biomedical) and iCa and pH were measured with a Rapid Point 500 blood gas analyzer (Siemens). Albumin, total calcium and total magnesium were analyzed with a Siemens Atellica CH. Analytical interference of iCa with iMg and vice versa was investigated using unbuffered saline solutions.

RESULTS

In the studied patient population, no significant correlations were observed between iMg and iCa, albumin, and pH. An inverse relationship was observed between iCa and Mg-ISE. For every 0.1 mmol/L change in iCa concentration, the iMg concentration deviated by 0.01 mmol/L at an iMg concentration of 0.5 mmol/L and by 0.013 mmol/L at an iMg concentration of 1.0 mmol/L. The measurement of iCa was not affected by iMg.

CONCLUSIONS

In vivo, no correlation was observed between iMg with iCa, albumin and pH. Interference of iCa on iMg measurement was noted, with a maximum deviation of ±0.02 mmol/L iMg across the reference range of iCa (1.15-1.32 mmol/L). Additionally, the iCa measurement was not affected by the iMg concentration.

摘要

目的

本研究旨在确定离子化镁（iMg）与离子化钙（iCa）、总钙、白蛋白和 pH 值的体内相关性。此外，还定义了 iCa 对 Stat Profile Prime Plus（Nova Biomedical）上 iMg 测量的分析干扰以及反之亦然。

方法

对入住重症监护病房的 109 名不同患者的 238 对血气样本进行了 iCa、iMg 和 pH 值的体内相关性研究。在肝素化血浆样本中测量白蛋白和总镁（tMg）。iMg 的测量使用 Stat Profile Prime Plus（Nova Biomedical）的离子选择性镁电极（ISE）进行，iCa 和 pH 值使用 Rapid Point 500 血气分析仪（Siemens）进行测量。白蛋白、总钙和总镁使用 Siemens Atellica CH 进行分析。使用无缓冲生理盐水溶液研究了 iCa 对 iMg 和反之亦然的分析干扰。

结果

在所研究的患者人群中，未观察到 iMg 与 iCa、白蛋白和 pH 值之间存在显著相关性。观察到 iCa 与 Mg-ISE 之间存在反比关系。当 iCa 浓度每变化 0.1 mmol/L 时，在 iMg 浓度为 0.5 mmol/L 时，iMg 浓度偏差 0.01 mmol/L，在 iMg 浓度为 1.0 mmol/L 时，iMg 浓度偏差 0.013 mmol/L。iCa 的测量不受 iMg 的影响。