在重症患者中,电离和总之间的关联:前性队列研究
Eyrun A Kristinsdottir1,2, Svajunas Statkevicius1, Martin I Sigurdsson3,4
1Department of Perioperative and Intensive Care, Skåne University Hospital, Lund, Sweden.
概括
总 (tMg) 和电离 (iMg) 具有很强的相关性,但在较高度下,tMg 越来越偏离生物活性 iMg. 这表明使用tMg来估计iMg在临床应用中是不可靠的.
科学领域:
- 临床化学 临床化学
- 生物化学 生物化学
- 医学诊断 医学诊断 医学诊断
背景情况:
- 临床实验室通常测量总 (tMg),包括电离 (iMg) 和结合形式.
- 只有的电离分数 (iMg) 是生物活性.
- 诸如酸状态和蛋白质度等因素可以影响tMg和iMg之间的关系.
研究的目的:
- 评估总 (tMg) 和电离 (iMg) 测量之间的关系和一致性.
- 评估在临床环境中使用tMg来估计生物活性IMg的可靠性.
主要方法:
- 一项多中心观察性研究,使用在2小时窗口内收集的配对tMg和iMg样本.
- 统计分析包括线性回归,皮尔森相关系数和布兰德-阿尔特曼分析.
- 多变量回归确定了独立与度相关的因素.
主要成果:
- 电离 (iMg) 占总 (tMg) 的77.9%.
- 在iMg和tMg之间发现了强烈的相关性 (r=0.916).
- 布兰德-阿尔特曼分析显示出比例偏差,在较高度下,差异越来越大.
结论:
- 虽然iMg和tMg有很强的相关性,但比例偏差表明tMg在更高水平的iMg中是一个越来越不可靠的指标.
- 从tMg估计iMg的衍生方程由于观察到的偏差,因此在临床上不可靠.
- 临床决策应考虑使用tMg作为iMg的替代品的局限性,特别是在高度时.
相关概念视频
Common Ion Effect
47.7K
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Châtelier’s principle. Consider the dissolution of silver iodide:
47.7K
Roles of Electrolytes: Chloride and Bicarbonate
1.3K
Chloride ions contribute to the osmotic pressure gradient distinguishing the intracellular fluid (ICF) from the extracellular fluid (ECF). They counterbalance positively charged ions in the ECF and ensure its electrochemical stability. The renal system's process of chloride absorption and release generally mirrors that of sodium ions.
Conditions such as hypochloremia can arise from insufficient chloride reabsorption by the kidneys, often compounded by extended bouts of diarrhea, vomiting,...
Conditions such as hypochloremia can arise from insufficient chloride reabsorption by the kidneys, often compounded by extended bouts of diarrhea, vomiting,...
1.3K
Ionic Association
155
The ionic association is the association of oppositely charged ions in an electrolyte solution to form ion pairs. Bjerrum defined ion pairs as two oppositely charged ions whose electrostatic attraction exceeds the thermal energy of the system, typically expressed as 2kT. Electrostatic attraction depends on ionic charge, separation distance, and the dielectric constant of the medium. Thermal energy, represented by kT, reflects the tendency of ions to move independently due to molecular motion.
155
Ionic Strength: Overview
3.4K
The ionic strength of a solution is a quantitative way of expressing the total electrolyte concentration of a solution. This concept was first introduced in 1921 by two American physical chemists, Gilbert N. Lewis and Merle Randall, while describing the activity coefficient of strong electrolytes. During the calculation of ionic strength (I or μ), all the cations and anions are considered. However, the concentration (c) of an ion with a greater charge number (z) has a greater contribution...
3.4K
Qualitative Analysis
27.5K
For solutions containing mixtures of different cations, the identity of each cation can be determined by qualitative analysis. This technique involves a series of selective precipitations with different chemical reagents, each reaction producing a characteristic precipitate for a specific group of cations. Metal ions within a group are further separated by varying the pH, heating the mixture to redissolve a precipitate, or adding other reagents to form complex ions.
For instance, group IV...
For instance, group IV...
27.5K
Ionic Strength: Effects on Chemical Equilibria
3.0K
The addition of an inert ionic compound increases the solubility of a sparingly soluble salt. For example, adding potassium nitrate to a saturated solution of calcium sulfate significantly enhances the solubility of calcium sulfate. Le Châtelier's principle cannot predict this shift in the equilibrium. Instead, this could be explained in terms of changes in the effective concentration of the ions in solution in the presence of added inert salt.
In this solution, the primary...
In this solution, the primary...
3.0K


