Department of Internal Medicine and Aged Care, Cancer Care Services, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.
Intern Med J. 2011 Jul;41(7):537-43. doi: 10.1111/j.1445-5994.2009.02160.x.
Accurate knowledge of the glomerular filtration rate (GFR) is imperative in the intensive care unit (ICU) as renal status is important for medical decisions, including drug dosing.
Recently, an estimation of GFR (eGFR) was suggested as a method of estimating GFR. How well this formula predicts GFR in unwell patients with normal initial serum creatinine concentrations has not been examined.
The accuracy of the eGFR (before and after adjustment for actual body surface area (BSA)) was compared with measured and with estimated creatinine clearance using the Cockcroft Gault (CG) formula adjusted for total and lean body weight.
A total of 237 observations was recorded in 47 subjects. These were initially analysed independently, and then using the first observation only. Overall the mean difference between measured creatinine clearance and eGFR was -12 mL/min (95% confidence interval (CI) -20 to -3), between measured creatinine clearance and CG +17 mL/min (95% CI 9-24), between measured creatinine clearance and CG adjusted for ideal body weight +12 mL/min (95% CI 4-21) and between measured creatinine clearance and eGFR 'unadjusted' for BSA 5 mL/min (95% CI -2-13).
Using either eGFR or CG formulae to estimate renal function in ICU subjects with normal serum creatinine concentrations is inaccurate. Although correcting for BSA improves the eGFR, this requirement to measure height and weight removes a major attraction for its use. We suggest that eGFR should not be automatically calculated in the ICU setting.
在重症监护病房（ICU）中，准确了解肾小球滤过率（GFR）至关重要，因为肾脏状况对于包括药物剂量在内的医疗决策很重要。
最近，提出了一种估计 GFR（eGFR）的方法作为估计 GFR 的方法。尚未检查该公式在初始血清肌酐浓度正常的病情不佳的患者中预测 GFR 的效果如何。
比较了 eGFR（在根据实际体表面积（BSA）进行调整前后）与使用 Cockcroft-Gault（CG）公式根据总体重和去脂体重调整的估计肌酐清除率与实测肌酐清除率的准确性。
47 例患者共记录了 237 个观察值。这些观察值最初是独立分析的，然后仅使用第一次观察值。总体而言，实测肌酐清除率与 eGFR 之间的平均差异为-12 mL/min（95%置信区间（CI）-20 至-3），实测肌酐清除率与 CG 之间为+17 mL/min（95%CI 9-24），实测肌酐清除率与 CG 调整为理想体重之间为+12 mL/min（95%CI 4-21），实测肌酐清除率与未调整 BSA 的 eGFR 之间为+5 mL/min（95%CI -2-13）。
在血清肌酐浓度正常的 ICU 患者中，使用 eGFR 或 CG 公式估计肾功能均不准确。尽管通过 BSA 校正可以改善 eGFR，但这需要测量身高和体重，这使其使用失去了很大的吸引力。我们建议在 ICU 环境中不应自动计算 eGFR。
