Rodriguez M, Pederson J A, Llach F
Kidney Int. 1985 Nov;28(5):808-13. doi: 10.1038/ki.1985.202.
The effect of regular dialysis and isolated ultrafiltration on plasma osmolality, plasma colloid osmotic pressure (COP), plasma volume, and vascular refilling rate was evaluated in maintenance dialysis patients. Nineteen patients underwent regular dialysis and 11 isolated ultrafiltration. Blood samples from these subjects were obtained from arterial or venous dialysis system ports and peripheral veins. For any decrease in plasma volume, there was an increment in COP with each procedure in both venous and arterial ports and the presence of a progressive decrease of plasma osmolality was observed only during regular dialysis. Second, five additional patients underwent 2 hrs of regular dialysis and isolated ultrafiltration in separate sessions removing comparable amounts of fluid (approximately 2.5 liter); after 2 hrs, there were no differences in the changes of plasma volume and COP, but again plasma osmolality decreased only during regular dialysis. These studies demonstrate that moderate changes in plasma osmolality do not affect COP. Furthermore, the ability of the plasma to recruit fluid and generate vascular refilling (as assessed by COP) is similar during regular dialysis and isolated ultrafiltration, provided the rates of ultrafiltration are the same.
在维持性透析患者中评估了常规透析和单纯超滤对血浆渗透压、血浆胶体渗透压（COP）、血浆容量和血管再充盈率的影响。19例患者接受常规透析，11例接受单纯超滤。这些受试者的血样取自动脉或静脉透析系统端口以及外周静脉。对于血浆容量的任何减少，在静脉和动脉端口的每个操作过程中COP都会增加，并且仅在常规透析期间观察到血浆渗透压逐渐降低。其次，另外5例患者在单独的疗程中分别进行了2小时的常规透析和单纯超滤，去除相当量的液体（约2.5升）；2小时后，血浆容量和COP的变化没有差异，但同样仅在常规透析期间血浆渗透压降低。这些研究表明，血浆渗透压的适度变化不会影响COP。此外，在常规透析和单纯超滤期间，只要超滤速率相同，血浆募集液体并产生血管再充盈的能力（通过COP评估）是相似的。
