Department of Renal Medicine, Tan Tock Seng Hospital, Singapore, Singapore,
Nephron. 2020;144(6):299-303. doi: 10.1159/000507260. Epub 2020 May 5.
Drug dosing in patients with acute kidney injury (AKI) is based on the Cockroft-Gault (CG) equation-derived estimated Creatinine clearance (CGeCrCl) for historical reasons due to the lack of a validated method for estimating glomerular filtration rate (GFR) when Cr is rapidly changing. The kinetic equation (kinetic estimated GFR [KeGFR]) estimates GFR for the nonsteady-state Cr level. It is being validated in patient cohorts and could potentially be used for drug dosing when the Cr level is in the nonsteady state.
The aim of the study was to measure the concordance and the degree of agreement between KeGFR-, CGeCrCl, and MDRD eGFR-based drug dosing categories in patients with nonsteady Cr levels.
In the pilot study published previously, 80 adult patients with a significant change in Cr level after admission to the acute medical ward were classified as per the Acute Kidney Injury Network (AKIN) criteria and compared to a KeGFR-based criterion. The CG equation and the MDRD equation were applied retrospectively to the same dataset, and the concordance of the eGFR categories between the 3 methods was studied. The 3 eGFR categories (<30, 30-49, and >50 mL/min) were chosen to reflect the frequently used drug dosing categories in patients with renal impairment.
The concordance between CGeCRCL and KeGFR for drug dosing categories was only 62%, with 27 (90%) of the 30 discordant subjects falling into a higher eGFR category when KeGFR was used. The agreement between KeGFR and CGeCrCl was also unsatisfactory. There was better concordance (75%), but the agreement was also not satisfactory between MDRD eGFR and KeGFR for the drug dosing categories.
In AKI, compared to CGeCrCL, using KeGFR may affect drug dosing significantly by changing the eGFR category. Further studies of KeGFR for drug dosing will need therapeutic drug monitoring and pharmacokinetic studies for validation.
由于缺乏快速变化时 Cr 水平的肾小球滤过率（GFR）验证方法，出于历史原因，在急性肾损伤（AKI）患者中，药物剂量是基于 Cockroft-Gault（CG）方程衍生的估计肌酐清除率（CGeCrCl）。动力学方程（动力学估计肾小球滤过率[KeGFR]）用于估计 Cr 水平处于非稳态时的 GFR。它正在患者队列中进行验证，并且当 Cr 水平处于非稳态时，它可能被用于药物剂量。
本研究的目的是测量 KeGFR、CGeCrCl 和 MDRD eGFR 基于药物剂量分类在 Cr 水平非稳定患者中的一致性和吻合度。
在之前发表的试点研究中，80 名因入院至急性内科病房而 Cr 水平显著变化的成年患者根据急性肾损伤网络（AKIN）标准进行分类，并与基于 KeGFR 的标准进行比较。CG 方程和 MDRD 方程被应用于同一数据集的回顾性分析，并研究了 3 种方法的 eGFR 分类的一致性。选择 3 个 eGFR 类别（<30、30-49 和>50 mL/min）以反映肾功能不全患者中常用的药物剂量类别。
CGeCRCL 和 KeGFR 用于药物剂量类别的一致性仅为 62%，当使用 KeGFR 时，27（90%）个不一致的患者中有 27 个进入了更高的 eGFR 类别。KeGFR 和 CGeCrCl 之间的一致性也不理想。在药物剂量类别方面，MDRD eGFR 和 KeGFR 之间的一致性（75%）更好，但也不理想。
在 AKI 中，与 CGeCrCL 相比，使用 KeGFR 可能会通过改变 eGFR 类别而显著影响药物剂量。还需要治疗药物监测和药代动力学研究来验证 KeGFR 用于药物剂量。
