Baptista João Pedro, Neves Marta, Rodrigues Luis, Teixeira Luísa, Pinho João, Pimentel Jorge
Centro Hospitalar Universitário Coimbra, Coimbra, Portugal,
J Nephrol. 2014 Aug;27(4):403-10. doi: 10.1007/s40620-013-0036-x. Epub 2014 Jan 21.
Accuracy of glomerular filtration rate (GFR) estimates has been questioned and several authors recommend routine use of measured renal creatinine clearance (CLCR) as a surrogate of GFR in the intensive care unit (ICU). Our purpose was to compare estimates of GFR using Cockroft-Gault (CG), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease Study (MDRD) equations with 8h-CLCR, within a population of critically ill patients with a wide range of measured CLCR.
Through a prospective, observational study of 54 patients with normal serum creatinine (sCr) admitted to ICU, daily 8h-CLCR (reference method) and GFR estimates (644 paired samples) were matched and compared. Augmented renal clearance (ARC) was defined as 8h-CLCR >130 ml/min/1.73 m(2).
No significant difference was found between mean 8h-CLCR (135.5 ml/min/1.73 m(2)) and CG equation (135.7 ml/min/1.73 m(2)), but significant differences (p < 0.01) were found for the MDRD (124.4 ml/min/1.73 m(2)) and CKD-EPI (107.6 ml/min/1.73 m(2)) equations. Correlation between 8h-CLCR and all estimates was weak (R = 0.2, 0.19 and 0.34, respectively). We observed poor agreement in terms of precision (40.9, 39.8 and 33.4%, respectively). Analysing subgroups, we observed that all equations significantly underestimated 8h-CLCR >120 ml/min/1.73 m(2) and overestimated 8h-CLCR <120 ml/min/1.73 m(2) (p < 0.05). The incidence of ARC patients was 55.6%.
Estimates of GFR using CG, CKD-EPI and MDRD formulae are flawed in the critically ill with normal sCr, significantly underestimating renal function in those with ARC and overestimating it in those with normal or decreased 8h-CLCR. Globally, the population exhibited ARC on more than half of the ICU admission days.
肾小球滤过率（GFR）估算的准确性受到质疑，多位作者建议在重症监护病房（ICU）常规使用测量的肌酐清除率（CLCR）作为GFR的替代指标。我们的目的是在一组测量的CLCR范围广泛的重症患者中，比较使用Cockcroft-Gault（CG）、慢性肾脏病流行病学协作组（CKD-EPI）和肾脏病饮食改良研究（MDRD）方程估算的GFR与8小时CLCR。
通过对54例入住ICU且血清肌酐（sCr）正常的患者进行前瞻性观察研究，将每日的8小时CLCR（参考方法）和GFR估算值（644对样本）进行匹配和比较。将强化肾清除率（ARC）定义为8小时CLCR>130 ml/min/1.73 m²。
8小时平均CLCR（135.5 ml/min/1.73 m²）与CG方程（135.7 ml/min/1.73 m²）之间未发现显著差异，但MDRD方程（124.4 ml/min/1.73 m²）和CKD-EPI方程（107.6 ml/min/1.73 m²）存在显著差异（p<0.01）。8小时CLCR与所有估算值之间的相关性较弱（分别为R = 0.2、0.19和0.34）。我们观察到在精密度方面一致性较差（分别为40.9%、39.8%和33.4%）。分析亚组时，我们观察到所有方程均显著低估8小时CLCR>120 ml/min/1.73 m²的情况，而高估8小时CLCR<120 ml/min/1.73 m²的情况（p<0.05）。ARC患者的发生率为55.6%。
在sCr正常的重症患者中，使用CG、CKD-EPI和MDRD公式估算GFR存在缺陷，显著低估了ARC患者的肾功能，而高估了8小时CLCR正常或降低患者的肾功能。总体而言，该人群在超过一半的ICU住院日表现出ARC。
