[Lyophilized plasmas for the control of thromboplastin time values and calibration of thromboplastins]

Abstract

The paper deals with the production of normal and pathological plasmas for the calibration of thromboplastin. Calibration is performed according to WHO principles. We compared single charges of thromboplastin (Sevac, CSSR, human brain) with each other and a selected reference charge with British thromboplastin. Lyophilised reference plasmas produced (20-50 healthy blood donors) and plasmas taken from patients treated with coumarin derivates (single and mixtures) could replace their fresh equivalents which was confirmed by testing 4 different batches. The stability of these plasmas (for a time of at least 12 months) was proved by repeated checks. These plasmas also served as controls in other laboratories in Czechoslovakia.