Observation of the changes of plasma proteins after long term plasmapheresis.

The influence of long term plasmapheresis on the health of donors was examined in two groups of plasma donors that donated mean volume of 411 ml of plasma during 176 weeks and 670 ml of plasma during 123 weeks (p less than 0,05). The control group consisted of 27 whole blood donors. Statistically no significant differences (p greater than 0,05) were found in the concentrations of total proteins, albumin, gammaglobulins, immunoglobulins, alpha 1 antitrypsin, alpha 2 macroglobulin, plasminogen, fibrinogen, factor V, factor VIII, GPT and alkaline phosphatase. Although the difference was significant for bilirubin and GOT the mean values were within the normal range. Significant elevations were found in alpha 1 globulins, and alpha 2 globulins in the group that donated 411 ml of plasma/week after 35 sessions. In this latter group of donors the elevation of beta globulins was observed after 100 sessions. On the basis of these results we suggest that plasma donors should not donate more than 500 ml of plasma per week and that the maximal number of regular plasmapheresis should not exceed 70. The yearly number of sessions should therefore not exceed 50 and the yearly donated volume of plasma should be not more than 25 liters.