Anaesthesiology and Resuscitation Department, Ramón y Cajal University Hospital, Ramón y Cajal Institute of Health Research, IRYCIS, Acute Kidney Failure Research Consortium, CIFRA, Madrid, Spain.
Nefrologia. 2012;32(1):53-8. doi: 10.3265/Nefrologia.pre2011.Oct.11102. Epub 2011 Nov 11.
The current definition and classification of acute kidney injury is based on consensus criteria (RIFLE and AKIN systems). Creatinine is the most commonly used of the recommended parameters (creatinine, glomerular filtration rate and diuresis). If the baseline value is not known, it can be calculated based on the simplified MDRD equation, assuming a filtration rate of 75 ml/min/1.73 m2 for the calculation. The aim of this study was to evaluate the diagnostic impact of using estimated baseline creatinine compared to the actual value measured in patients undergoing cardiac surgery.
Analysis of patients undergoing major cardiac surgery, who were prospectively included in a database. The maximum RIFLE stage reached was calculated for each patient using the measured and estimated baseline creatinine levels. The impact on the diagnosis was analysed using intraclass correlation coefficients, concordance analysis and Bland-Altman plots.
The incidence of postoperative acute kidney injury in 2103 cases between 2002 and 2007 was 29.1%, according to estimated creatinine (14.3% with the measure). This represents an overestimation of 104%, with an intraclass correlation of 0.12. By excluding patients with known chronic kidney disease (glomerular filtration rate [<60 ml/min/1.73 m2), both the overestimation (2.4%) and the correlation (0.57) improved.
The calculation of baseline creatinine using the MDRD equation overestimates the incidence of acute kidney injury after cardiac surgery, and is an inadequate method for detection when the baseline value is unknown.
急性肾损伤的当前定义和分类基于共识标准（RIFLE 和 AKIN 系统）。肌酐是推荐参数中最常用的（肌酐、肾小球滤过率和利尿）。如果不知道基线值，可以根据简化的 MDRD 方程进行计算，假设计算时滤过率为 75 ml/min/1.73 m2。本研究的目的是评估在接受心脏手术的患者中使用估计的基线肌酐与实际测量值相比的诊断影响。
对接受大型心脏手术的患者进行前瞻性分析，将其纳入数据库。使用测量和估计的基线肌酐水平计算每位患者达到的最大 RIFLE 阶段。使用组内相关系数、一致性分析和 Bland-Altman 图分析诊断的影响。
2002 年至 2007 年间，2103 例患者术后急性肾损伤的发生率为 29.1%，根据估计肌酐（14.3%为实测值）。这表示高估了 104%，组内相关系数为 0.12。排除已知慢性肾脏病患者（肾小球滤过率 [<60 ml/min/1.73 m2）后，高估（2.4%）和相关性（0.57）均有所改善。
使用 MDRD 方程计算基线肌酐会高估心脏手术后急性肾损伤的发生率，并且在基线值未知时，这是一种不充分的检测方法。
