Leypoldt John K, Cheung Alfred K, Deeter R Barry, Goldfarb-Rumyantzev Alexander, Greene Tom, Depner Thomas A, Kusek John
VA Salt Lake City Health Care System, Salt Lake City, Utah, USA.
Kidney Int. 2004 Oct;66(4):1669-76. doi: 10.1111/j.1523-1755.2004.00934.x.
Daily short hemodialysis (HD) is often prescribed by simply doubling treatment frequency and halving treatment time; however, the effect of this prescription approach on the equilibrated HD dose (urea eKt/V) and whole body clearance for beta(2)-microglobulin has not been established.
We compared urea and beta(2)-microglobulin kinetics during and 60 minutes after a short HD treatment and a conventional HD treatment in a crossover study on 22 maintenance HD patients: 16 male and 6 female, 61 +/- 18 (mean +/- standard deviation) years of age. One patient in each treatment modality was excluded from certain analyses because of missing data. Short and conventional HD treatments were essentially identical, except for treatment times, which were 116 +/- 14 and 241 +/- 27 minutes, respectively. Blood samples were collected at regular intervals during and after treatments, and additional blood and dialysate samples were collected at 60 minutes of treatment to evaluate dialyzer clearances.
Plasma water urea clearances measured directly across the dialyzer during short and conventional HD treatments were not different (255 +/- 23 mL/min and 255 +/- 28 mL/min, respectively). The 60-minute postdialysis blood urea nitrogen concentration rebounded more (P < 0.01) after short HD than conventional HD (5.9 +/- 3.1 vs. 4.0 +/- 1.5 mg/dL, respectively). Calculated urea eKt/V values using the Daugirdas-Schneditz rate equation were not different from those measured during conventional HD using the 60-minute postdialysis concentration but significantly overestimated measured urea eKt/V values during short HD. Postdialysis rebound of beta(2)-microglobulin concentrations was variable but similar after short and conventional HD treatments (0.1 +/- 3.4 vs. 0.7 +/- 1.8 mg/L, respectively). Whole body clearances of beta(2)-microglobulin calculated from predialysis and immediate (10-second) postdialysis serum concentrations during short and conventional HD treatments were not different from each other (42.9 +/- 24.1 vs. 41.9 +/- 22.4 mL/min, respectively).
These observations show that the Daugirdas-Schneditz rate equation is accurate in predicting urea eKt/V during conventional, but not during short, HD. In contrast, whole body clearances of beta(2)-microglobulin during short and conventional HD treatments were similar. We conclude that calculation of accurate estimates of urea eKt/V, but not clearances of beta(2)-microglobulin, differ during short and conventional HD treatments.
每日短时血液透析（HD）通常通过简单地将治疗频率加倍和治疗时间减半来进行处方；然而，这种处方方法对平衡HD剂量（尿素eKt/V）和β2微球蛋白的全身清除率的影响尚未明确。
我们在一项交叉研究中比较了22例维持性HD患者（16例男性和6例女性，年龄61±18岁，均值±标准差）在短时HD治疗和传统HD治疗期间及治疗后60分钟的尿素和β2微球蛋白动力学。由于数据缺失，每种治疗方式中有1例患者被排除在某些分析之外。短时和传统HD治疗基本相同，只是治疗时间分别为116±14分钟和241±27分钟。在治疗期间和治疗后定期采集血样，并在治疗60分钟时采集额外的血液和透析液样本以评估透析器清除率。
在短时和传统HD治疗期间直接通过透析器测得的血浆水尿素清除率无差异（分别为255±23 mL/分钟和255±28 mL/分钟）。短时HD后60分钟的透析后血尿素氮浓度反弹比传统HD更明显（P<0.01）（分别为5.9±3.1 vs. 4.0±1.5 mg/dL）。使用Daugirdas-Schneditz速率方程计算的尿素eKt/V值与使用透析后60分钟浓度在传统HD期间测得的值无差异，但在短时HD期间显著高估了测得的尿素eKt/V值。β2微球蛋白浓度的透析后反弹是可变的，但在短时和传统HD治疗后相似（分别为0.1±3.4 vs. 0.7±1.8 mg/L）。在短时和传统HD治疗期间，根据透析前和透析后即刻（10秒）血清浓度计算的β2微球蛋白全身清除率彼此无差异（分别为42.9±24.1 vs. 41.9±22.4 mL/分钟）。
这些观察结果表明，Daugirdas-Schneditz速率方程在预测传统HD期间的尿素eKt/V时准确，但在短时HD期间不准确。相比之下，短时和传统HD治疗期间β2微球蛋白的全身清除率相似。我们得出结论，在短时和传统HD治疗期间，准确估计尿素eKt/V的计算方法不同，但β2微球蛋白清除率的计算方法相同。
