STORAGE STABILITY OF FRESH-FROZEN PLASMA - RESULTS OF A 6-MONTH STORAGE AT -20-DEGREES-C AND -25-DEGREES-C - RING STUDY OF THE WORKING GROUP BLOOD-PLASMA CONSTITUENTS OF THE DEUTSCHE GESELLSCHAFT FUR TRANSFUSIONSMEDIZIN UND IMMUNHAMATOLOGIE (DGTI)

Background: In October 1995 the working group 'Blood Plasma Constituen ts' of the DGTI has begun a multicenter study with three types of fres h-frozen plasma (FFP) to determine their storage stability at four tem peratures (-20 degrees C; -25 degrees C; -30 degrees C; -40 degrees C) , since the European Pharmacopoeia (EP) monography on 'Human Plasma fo r Fractionation' gives no information for its storage stability. Aim o f the ring study was the determination of the storage stability of FFP at four temperatures by testing characteristic plasma proteins. Mater ial and Methods: The FFPs were manufactured by three different blood b anks in Germany. Two FFPs were manufactured from whole blood which was pooled and frozen in aliquots in blood bags within 6 h to 24 h after the blood donation. The third FFP pool was manufactured from plasmaphe resis plasma and frozen in aliquots within 4 h after the plasma donati on. The storage stability of the FFPs was tested by measuring the acti vity of the coagulation factors FVIII, FIX, FV and fibrinogen, the act ivation products TAT (thrombin/antithrombin complex) and prothrombin f ragment Fl and F2, the inhibitors antithrombin and C1-esterase inhibit or, the IgG content, and the anti-HBs titer. 13 laboratories from Euro pe participated in the ring study. Proteins and protein activities wer e determined using commercial reagents. Results: The storage stability of the FFPs was investigated for 6 months at storage temperatures -20 degrees C and -25 degrees C by testing characteristic proteins of the Fm. The comparison of the measured values for the different proteins tested at the beginning of the storage and after 6 months showed no si gnificant changes of these values, with one exception, the FVIII aciti vity of the FFP which was manufactured from whole blood and frozen wit hin 4 h after the blood donation. The FVIII content of this plasma was diminished by 9% compared with the starting value. Conclusion: In the ring study of the DGTI Working Group No. 2 the investigation of the s torage stability of the FFPs will be conducted over a time period of 3 years to allow a statement on the storage stability of these Fms afte r this time and the influence of the different storage temperatures.