Slow thaw siphon technique for cryoprecipitate production.

The efficacy of the slow thaw siphon technique for making cryoprecipitate was evaluated. A hundred consecutive bags of cryoprecipitate were subjected to analysis. The average Factor VIII:C level in donors plasma was 1.02 IU/ml with slightly lower levels of Factor VIII:C in O group persons and in the older age group. The average Factor VIII:C content per bag of cryoprecipitate was 132 units with the average Factor VIII:C yield of 57.8 per cent. Recovery of the cryoprecipitates made by this method was tested in vivo in ten haemophiliacs with less than 1 per cent activity. An average increment of 1.91 per cent in Factor VIII:C levels was obtained by infusion of 1 IU/kg body weight.