长度与血清肌酐比值不能预测危重症儿童的实测肌酐清除率。

Length/serum creatinine ratio does not predict measured creatinine clearance in critically ill children.

作者信息

Fong J, Johnston S, Valentino T, Notterman D

机构信息

Division of Pediatric Critical Care, New York Hospital-Cornell Medical Center, NY 10021, USA.

出版信息

Clin Pharmacol Ther. 1995 Aug;58(2):192-7. doi: 10.1016/0009-9236(95)90197-3.

DOI:10.1016/0009-9236(95)90197-3

PMID:7648769

Abstract

OBJECTIVE

Information regarding renal function is important in critically ill children to adjust the dosage of drugs that are eliminated by the kidneys. Methods for estimating glomerular filtration rate (GFR) based on age and serum creatinine level have shown good agreement with measured creatinine clearance (CLCR) in children without critical illness but have not been examined in critically ill children.

METHODS

CLCR (24 hours) was measured (CLCR-measured) in 100 individuals (aged 5.6 years [range, 0.1 to 20.8 years]) admitted to a pediatric intensive care unit. Urine was collected by indwelling bladder catheters. Serum levels were determined. CLCR was calculated (CLCR-measured) according to the standard formula. GFR was estimated (CL-estimated) according to a published method, in which GFR is based on serum creatinine levels, patient length, and a constant that varies with the age and sex of the child. For each patient, the percentage difference between methods was calculated as the difference between the methods divided by the average obtained by the two methods and expressed as a percentage. Bias was calculated as the absolute value of the percentage difference.

RESULTS

CLCR-measured and CL-estimated were significantly correlated (CLCR-measured = 0.57 CL-estimated + 16.8; r = 0.68; p < 0.001). However, CL-estimated was greater than CLCR-measured in 84 patients. The difference ranged from -230 to +123 ml/min/1.73 m2 (mean -25.9 ml/min/1.73 m2 [95% confidence interval, -18.1 to 33.7 ml/min/1.73 m2]). The mean percentage difference between the methods was also large (-38.1% [95% confidence interval, -47.1% to 29.2%]) and ranged from -153.2% to 102.1%. The mean bias was 45.2% (95% confidence interval, 37.7% to 52.8%). In 36 of 100 patients the discrepancy between the two methods was greater than 50%. Adjusting for weight percentile, as a proxy for abnormal muscle mass, did not improve the model.

CONCLUSION

A method to estimate GFR in children that is based on age and sex, but not critical illness, does not correspond with measured 24-hour CLCR. Use of this method to adjust dosage of drugs eliminated by the kidney might result in significant overdosage in most critically ill children.

摘要

目的

对于危重症儿童而言，有关肾功能的信息对于调整经肾脏排泄的药物剂量很重要。基于年龄和血清肌酐水平估算肾小球滤过率（GFR）的方法，在非危重症儿童中与测得的肌酐清除率（CLCR）显示出良好的一致性，但尚未在危重症儿童中进行检验。

方法

对收入儿科重症监护病房的100名个体（年龄5.6岁[范围为0.1至20.8岁]）测量其24小时CLCR（实测CLCR）。通过留置膀胱导尿管收集尿液。测定血清水平。根据标准公式计算CLCR（实测CLCR）。根据一种已发表的方法估算GFR（估算CL），该方法中GFR基于血清肌酐水平、患者身高以及一个随儿童年龄和性别而异的常数。对于每位患者，计算两种方法之间的百分比差异，即两种方法的差值除以两种方法所得平均值并以百分比表示。偏差计算为百分比差异的绝对值。

结果

实测CLCR与估算CL显著相关（实测CLCR = 0.57估算CL + 16.8；r = 0.68；p < 0.001）。然而，在84例患者中估算CL大于实测CLCR。差异范围为 -230至 +123 ml/min/1.73 m²（平均 -25.9 ml/min/1.73 m² [95%置信区间，-18.1至 -33.7 ml/min/1.73 m²]）。两种方法之间的平均百分比差异也很大（-38.1% [95%置信区间，-47.1%至29.2%]），范围为 -153.2%至102.1%。平均偏差为45.2%（95%置信区间，37.7%至52.8%）。100例患者中有36例两种方法之间的差异大于50%。将体重百分位数作为异常肌肉量的替代指标进行校正，并未改善该模型。