Department of Critical Care, Pulmonary Unit, Evangelismos Hospital, National and Kapodistrian University of Athens, Medical School, Athens, Greece.
Anesthesiology Department, St. Elizabeth's Medical Center, Tufts Medical School, Boston, MA, United States of America.
PLoS One. 2018 Nov 26;13(11):e0207603. doi: 10.1371/journal.pone.0207603. eCollection 2018.
We aimed to examine the predictive value of a novel mathematical formula based on the law of conservation of mass in calculating sodium changes in intensive care unit patients and compare its performance with previously published formulae.
178 patients were enrolled from 01/2010 to 10/2013. Plasma and urine were collected in two consecutive 8-hour intervals and the sodium was measured. The predicted sodium concentration was calculated based on previous equations and our formula. The two 8-hour period (epoch 1 and 2) results were compared. Variability of predicted values among the measured range of serum sodium levels were provided by Bland-Altman plots with bias and precision statistics. Comparison of the results was performed with the statistical model of the Percentage Similarity.
47.19% patients had dysnatremias. The bias ± SD with 95% limits of agreement for sodium levels were -1.395±3.491 for epoch 1 and -1.623 ±11.1 for epoch 2 period. Bland-Altman analysis for the epoch 1 study period had the following results: -0.8079±3.447 for Adrogué-Madias, 0.56±9.687 for Barsoum-Levine, 0.1412±3.824 for EFWC and 0.294±4.789 for Kurtz-Nguyen formula. The mean similarity, SD and coefficient variation for the methods compared with the measured sodium are: 99.56%, 3.873, 3.89% epoch 1, 99.56%, 1.255, 1.26% for epoch 2, 99.77%, 1.245, 1.26% for Adrogue-Madias, 100.1%, 1.337, 1.34% for Barsoum-Levine, 100.1%, 1.704, 1.7% for Nguyen, 100.1%, 1.370, 1.37% for ECFW formula.
The law of conservation of mass can be successfully applied for the prediction of sodium changes in critically ill patients.
我们旨在检验一种基于质量守恒定律的新数学公式在计算重症监护病房患者钠变化方面的预测价值，并将其与先前发表的公式进行比较。
2010 年 1 月至 2013 年 10 月期间，连续 178 例患者入选。在两个连续的 8 小时间隔内采集血浆和尿液，并测量钠浓度。根据以前的方程和我们的公式计算预测的钠浓度。比较两个 8 小时期间（第 1 个和第 2 个时期）的结果。通过 Bland-Altman 图和偏倚和精度统计数据提供预测值在血清钠水平测量范围内的变异性。使用百分比相似性的统计模型进行结果比较。
47.19%的患者存在电解质紊乱。第 1 个时期的钠水平的偏倚±SD 和 95%一致性界限分别为-1.395±3.491 和-1.623±11.1。第 1 个时期的 Bland-Altman 分析结果如下：Adrogué-Madias 为-0.8079±3.447，Barsoum-Levine 为 0.56±9.687，EFWC 为 0.1412±3.824，Kurtz-Nguyen 公式为 0.294±4.789。与测量钠值相比，各方法的平均相似度、标准差和变异系数为：第 1 个时期为 99.56%、3.873、3.89%，第 2 个时期为 99.56%、1.255、1.26%，Adrogue-Madias 为 99.77%、1.245、1.26%，Barsoum-Levine 为 100.1%、1.337、1.34%，Nguyen 为 100.1%、1.704、1.7%，EFWC 为 100.1%、1.370、1.37%。
质量守恒定律可成功应用于预测重症监护病房患者的钠变化。
