Pedrini L A, Cozzi G, Faranna P, Mercieri A, Ruggiero P, Zerbi S, Feliciani A, Riva A
Nephrology and Dialysis Department, Bolognini Hospital of Seriate, Bergamo, Italy.
Kidney Int. 2006 Feb;69(3):573-9. doi: 10.1038/sj.ki.5000110.
The aim of the present study was transmembrane pressure (TMP) modulation in high-volume mixed hemodiafiltration (HDF) to optimize efficiency and minimize protein loss. The optimal flow/pressure conditions in on-line mixed HDF assisted with a feedback control of TMP were defined in this prospective randomized study in order to obtain maximal efficiency in solute removal while minimizing potential side effects. Two different TMP profiles in mixed HDF were compared in 12 unselected patients who underwent two study periods of 2 weeks each in cross-over randomized sequence: (A) constant TMP at around 300 mmHg and (B) profiled TMP, in which TMP was slowly increased from a low initial value to the maximal value. In both procedures, the mean volume exchange was 10.6+/-1.4 l/h. Mean filtration fraction was 53%. Instantaneous beta2-microglobulin (beta2-m) clearance was higher at the start of the session with profiled TMP (207+/-35 vs 194+/-28 ml/min, P<0.005), whereas no differences were found at the end (135+/-19 vs 132+/-19 ml/min). Profiled TMP resulted in a higher mean beta2-m clearance of the session (97.0+/-15.4 vs 87.8+/-18.3 ml/min, P<0.01), in lower albumin loss in the first 30 min (0.62+/-0.14 vs 0.98+/-0.18 g, P<0.0001), and, in the whole session (3.98+/-1.19 vs 5.24+/-0.77 g, P<0.001), in higher dialyzer ultrafiltration coefficients and lower resistance indexes. This study showed that the TMP feedback modulation in mixed HDF was highly effective in maintaining very high ultrafiltration rates and filtration fractions, and minimized potential side effects as a result of the improved preservation of membrane permeability and more favorable dialyzer pressure regimen.
本研究的目的是在高容量混合血液透析滤过（HDF）中调节跨膜压（TMP），以优化效率并使蛋白质损失最小化。在这项前瞻性随机研究中，确定了在线混合HDF中借助TMP反馈控制的最佳流量/压力条件，以便在溶质清除方面获得最大效率，同时将潜在副作用降至最低。在12例未经挑选的患者中比较了混合HDF中的两种不同TMP模式，这些患者以交叉随机顺序接受了两个为期2周的研究期：（A）恒定TMP在300 mmHg左右，（B）分段TMP，即TMP从低初始值缓慢增加到最大值。在这两种操作中，平均容量交换为10.6±1.4 l/h。平均滤过分数为53%。在分段TMP模式下，透析开始时的即时β2-微球蛋白（β2-m）清除率较高（207±35对194±28 ml/min，P<0.005），而结束时未发现差异（135±19对132±19 ml/min）。分段TMP导致透析期间的平均β2-m清除率更高（97.0±15.4对87.8±18.3 ml/min，P<0.01），在前30分钟内白蛋白损失更低（0.62±0.14对0.98±0.18 g，P<0.0001），并且在整个透析期间（3.98±1.19对5.24±0.77 g，P<0.001），透析器超滤系数更高且阻力指数更低。这项研究表明，混合HDF中的TMP反馈调节在维持非常高的超滤率和滤过分数方面非常有效，并且由于改善了膜通透性的保存和更有利的透析器压力方案，使潜在副作用最小化。
