[Comparison of the therapeutic effectiveness of membrane and centrifugation plasmapheresis]. / Srovnání úcinnosti lécebné membránové a centrifugacní plazmaferézy.

The authors compared 10 pairs of membrane plasmaphereses on an apparatus A 2008 PF and filter Plasmaflux P 2 with 10 centrifugation plasmaphereses on an apparatus Fenwal CS 3000. They evaluated the effectiveness by changes of plasma concentrations of total protein, albumin, beta 2 microglobulin, IgG, IgA, C3 complement, IgM, circulating immune complexes, urea, creatinine, uric acid, cholesterol, triacylglycerols and the clearance of these substances. Changes of plasma concentrations caused by plasmapheresis with the methods used did not differ in any of the investigated substances. The clearance of membrane plasmapheresis was for all substances higher than when the centrifugation method was used. Among values from which the clearance is determined no difference was proved between the two methods in the volume of exchanged plasma, the concentration of the substance in the removed plasma and its mid plasma concentration during the operation. The higher clearance of membrane plasmapheresis was due to the more rapid plasma exchange.

[Plasma proteins and other substances in membrane plasmapheresis. Relation to possibilities and limitations of this therapeutic method]. / Sledování plazmatických bílkovin a dalsích látek pri membránové plazmaferéze. Vztah k moznostem a omezením této lécebné metody.

The authors investigated the effectiveness of therapeutic membrane plasmapheresis and its influence on plasma concentrations of 17 proteins, cholesterol, triacylglycerols, urea, creatinine and uric acid. To this end they made 30 operations on monitors A 2008 PF with filters Plasmaflux P 2, where they exchanged one volume of plasma and replaced it with isooncotic albumin. They assessed the plasma concentrations of the investigated substances before, in the course of and after the operation, estimated sieving coefficients during the 15th and 90th minute and the clearance. Under conditions in vivo they confirmed that the sieving coefficients of the investigated substances approach the value of "1" and the clearance of the filtration rate, i.e. that the investigated substances pass easily through the plasmafilter and that plasmapheresis removes the substances non-selectively. They demonstrated that the assessment of plasma concentrations alone can lead to underestimation of the effectiveness of the operation. Assessment of sieving coefficients and clearance makes more adequate evaluation of the effectiveness of the procedure possible. Assessment of sieving coefficients and clearance made it obvious that plasma concentrations do not depend only on the amount of substance removed by plasmapheresis but also on other factors which must be investigated. The authors' findings support efforts to introduce methods for the selective removal of pathogenetic substances.