Use of segments for the quality control of the factor VIII: coagulant activity of fresh frozen plasma.

The storage of fresh frozen plasma (FFP) for short periods at -20 degrees C for 6 weeks, -30 degrees C for 12 weeks, or -40 degrees C for 12 weeks, did not result in significant deterioration in factor VIII: coagulant (factor VIII:C) activity in the primary packs. In studies examining whether plasma segments could be used for quality control purposes, the mean factor VIII:C activity of the primary pack was found to be identical to that of the attached segments of plasma for units of FFP which were thawed within 2 h after preparation. This was also true for FFP units stored at -40 and -60 degrees C for up to 12 weeks. There was, however, a loss in factor VIII:C activity in the segments of FFP units stored at either -20 or -30 degrees C for 6 and 12 weeks, respectively. Thus for units of FFP stored at temperatures colder than -40 degrees C, segments are suitable for assessing the factor VIII:C activity in the primary pack but not for FFP units stored at -20 or -30 degrees C.

The role of sulfinpyrazone in the prevention of arterio-venous shunt thrombosis.

The effect of sulfinpyrazone on the incidence of thrombosis of arterio-venous shunts was investigated in a double-blind crossover study in 45 patients on chronic hemodialysis over a period of 12 months. The incidence of thrombosis was reduced from 0.64 thrombi per patient month when on placebo to 0.21 thrombi per patient month when on sulfinpryazone (P less than 0.001). The therapeutic effect was more striking in men than in women and became evident within a week of starting the drug. The side effects were minimal, requiring withdrawal from the study of only one patient. This crossover study strengthens the findings in the previous report that sulfinpyrazone is of value in the prevention of thrombosis.