连续性静脉-静脉血液滤过对急性肾损伤患者胱抑素C浓度的影响

The effect of continuous renal replacement therapy in patients with acute kidney injury on the serum levels of urea,creatinine and cystatin C

目的:观察连续性静脉-静脉血液滤过(CVVH)置换剂量和持续时间对急性肾损伤(AKI)患者胱抑素C(CysC)浓度的影响。方法:将AKI伴少尿需行肾脏替代治疗患者纳入研究,予CVVH连续治疗24h以上,根据病情设定置换剂量分别为2L/h或4L/h。于CVVH治疗前及治疗第4、12、24小时抽取滤器前血液,第4小时抽取滤器后血液及超滤液,检测常用肾功能指标即尿素氮(BUN)、肌酐(SCr)和CysC的浓度。比较不同置换剂量和治疗时间点上述各指标的下降率,并计算滤器清除率和浓度时间曲线下面积(AUC)。结果:共纳入15例患者,其中2L/h剂量组7例,4L/h剂量组8例,两组间年龄构成、性别比例均无差异。CVVH治疗前2L/h剂量组BUN、SCr浓度均低于4L/h剂量组(P<0.05),CysC浓度差异无统计学意义。2L/h剂量组CVVH治疗第4、12、24小时滤器前BUN浓度较治疗前分别平均下降13.7%、43.0%、49.5%;SCr浓度分别平均下降12.7%、28.1%、54.5%;CysC浓度分别平均下降8.0%、23.0%、29.3%。CysC浓度下降率均低于同期BUN、SCr浓度下降率(P均<0.05)。2L/h剂量组BUN、SCr和CysC中位清除率分别为23.0ml/min、26.8ml/min和10.4ml/min,AUC分别为0.306mg/(L.h),0.252mg/(L.h),和0.190mg/(L.h)。4L/h剂量组CVVH治疗第4、12、24小时滤器前BUN浓度较治疗前分别平均下降12.3%、33.4%、56.5%,SCr浓度分别平均下降14.5%、29.4%、49.6%,CysC浓度分别平均下降10.2%、17.6%、29.7%。第12和24小时CysC浓度下降率均低于同期BUN、SCr浓度下降率(P均<0.05)。4L/h剂量组对BUN、SCr和CysC中位清除率分别为46.3ml/min、41.8ml/min和21.7ml/min,AUC分别为0.271mg/(L.h)、0.216mg/(L.h)和0.310mg/(L.h)。结论:CVVH置换剂量和持续时间对AKI患者的CysC浓度及清除率的影响均远低于BUN、SCr,提示用其反映肾功能的变化相对更为可靠。

Objective：Continuous veno-venous hemofiltration （CVVH） can affect the serum concentrations of usually used biomarkers to indicate renal function, like urea （ BUN ）, creatinine （SCr） and cystatin C （ CysC ）. In this study we investigate to what extent CVVH affects the concentrations of BUN, SCr and CysC independent on renal function change. Methodology ：Fifteen patients with oliguric acute AKI requiring CVVH were enrolled. Seven of them received CVVH in predilution mode at dose of 2 L/h and eight received CVVH in predilution mode at dose of 4 L/h. Samples were obtained from the afferent and efferent lines of the extracorporeal circuit and from the uhrafiltrate line at 4 different time points（O,4,12 and 24h） for measurement of BUN, SCr and CysC. Changes of serum levels of biomarkers over time, clearance of biomarkers and area under the curve（AUC） were analyzed. Results：Serum levels of BUN, SCr and CysC were gradually decreased at 4,12 and 24h during CVVH at dose of 2 L/h. Mean decreases of BUN at 4h, 12h,24h were 13. 7% ,43.0% and 49. 5% ; mean decreases of SCr were 12. 7% ,28. 1% and 54. 5% ; mean decreases of CysC were 8. 0% ,23.0% and 29. 3% ,respectively. Decreases of CysC at 24h were significantly less than the decreases of BUN and SCr （both P 〈 0. 05 ）. Mean clearance of BUN,SCr and CysC were 23.0 ml/min, 26. 8 ml/min and 10. 4 ml/min, and AUC of BUN, SCr and CysC were 0. 306 mg/（L＇h） ,0. 252 mg/（L＇h） and 0. 190 mg/（L.h）. Serum levels of BUN,SCr and CysC were gradually decreased at 4h,12h and 24h during CVVH at dose of 4 L/h. Mean decreases of BUN at 4h, 12h, 24h were 12. 3%, 33.4% and 56. 5% and 49. 5% ; mean decreases of SCr were lg. 5% ,29. 4% and 49.6% ; mean decreases of CysC werel0. 2% ,17.6% and 29. 7%, respectively. Decreases of CysC at 12h and 24h were significantly less than the decreases of BUN and Scr （both P 〈0. 05）. Mean clearance of BUN,SCr and CysC were 46. 3 ml/min,41.8 ml/min and 21.7 ml/min ,and AUC of BUN,SCr and CysC were 0.271 mg/（L-h）,0.216 mg/（L.h） and 0.310 mg/（L.h）. Conclusion：The alteration of serum levels of Cys C during CVVH is comparable with BUN and SCr.