Nicola Luca DE, Bellizzi Vincenzo, Minutolo Roberto, Cioffi Mario, Giannattasio Paolo, Terracciano Vincenzo, Iodice Carmela, Uccello Francesco, Memoli Bruno, Iorio Biagio Raffaele DI, Conte Giuseppe
Chair of Nephrology, School of Medicine, Second University of Naples, Italy.
Chair of Nephrology, School of Medicine, Lauria Hospital, Lauria, Italy.
J Am Soc Nephrol. 2000 Dec;11(12):2337-2343. doi: 10.1681/ASN.V11122337.
To evaluate the role of plasma tonicity in the postdialysis increment of plasma potassium (p[K(+)]), the outcome of two hemodiafiltration treatments that differed only in the Na(+) level in dialysate (Na(D))-143 mmol/L (high dialysate sodium concentration [H-Na(D)]) and 138 mmol/L (low dialysate sodium concentration [L-Na(D)])-were compared in the same group of uremic patients from the end of treatment (T0) to the subsequent 30 to 120 min and up to 68 h. Kt/V and intradialytic K(+) removal were comparable. At T0, plasma [Na(+)] was 145+/-1 and 137+/-1 mmol/L after H-Na(D) and L-Na(D), respectively (P<0.001). The difference in plasma tonicity persisted from T0 to T68 h. At T120, p[K(+)] was increased from the T0 value of 3.7+/-0.2 to 4.7+/-0.2 mmol/L (P<0.05) after H-Na(D), whereas it was unchanged after L-Na(D). The change of p[K(+)] was still different after 68 h (+76+/-10% and +50+/-7% in H-Na(D) and L-Na(D), respectively; P<0.05). Of note, in the first 2 h after the end of treatment, bioimpedance analysis revealed only in H-Na(D) a significant 11+/-3% decrement of phase angle that is compatible with a decrease of intracellular fluid volume at the expense of the extracellular volume. Similarly, within the same time frame, in H-Na(D), a significant reduction of mean corpuscular volume of red cells, associated with a 2 +/-1% decrease of the intracellular [K(+)], was observed. In contrast, mean corpuscular volume of red cells did not change and erythrocyte [K(+)] increased by 6+/-1% after L-Na(D) (P<0.005 versus H-Na(D)). Thus, hypertonicity significantly contributes to the increase of p[K(+)] throughout the whole interdialytic period by determining intracellular fluid volume/extracellular volume redistribution of water and K(+).
为评估血浆渗透压在透析后血浆钾（p[K⁺]）升高过程中的作用，在同一组尿毒症患者中比较了两种血液透析滤过治疗的结果，这两种治疗仅透析液中钠（Na(D)）水平不同——143 mmol/L（高透析液钠浓度 [H-Na(D)]）和138 mmol/L（低透析液钠浓度 [L-Na(D)]）——从治疗结束时（T0）至随后的30至120分钟以及长达68小时。Kt/V和透析期间钾（K⁺）清除率相当。在T0时，H-Na(D)和L-Na(D)后血浆[Na⁺]分别为145±1和137±1 mmol/L（P<0.001）。血浆渗透压的差异从T0持续到T68小时。在T120时，H-Na(D)后p[K⁺]从T0时的3.7±0.2 mmol/L升高至4.7±0.2 mmol/L（P<0.05），而L-Na(D)后则无变化。68小时后p[K⁺]的变化仍有差异（H-Na(D)和L-Na(D)分别为+76±10%和+50±7%；P<0.05）。值得注意的是，在治疗结束后的最初2小时内，生物电阻抗分析显示仅在H-Na(D)中有相角显著下降11±3%，这与细胞内液体积以细胞外液体积为代价减少相一致。同样，在同一时间范围内，在H-Na(D)中，观察到红细胞平均体积显著减小，同时细胞内[K⁺]降低2±1%。相反，L-Na(D)后红细胞平均体积未改变，红细胞[K⁺]增加6±1%（与H-Na(D)相比，P<0.005）。因此，高渗状态通过决定水和K⁺的细胞内液体积/细胞外液体积再分布，在整个透析间期显著促成p[K⁺]升高。
