Objective    To evaluate if routine leukocyte filtration for fresh frozen plasma (FFP) is necessary

so as to provide experimental base for appropriate uses of FFP.      Methods    Nine plasma preparation conditions were tested

in which plasma separation time and plasma residual were adjusted. A preparation method that could effectively decrease the leukocyte residual in plasma was found. Leukocyte residual in FFP from four blood centers was investigated. Five home-made plasma filters were used for FFP filtration and their effectiveness on leukocyte reduction in plasma was observed.      Results    Prolonged plasma separation time and increased plasma residual could decrease the leu

kocyte residual effectively and make it reach the leukocyte reduction standard (

<

1×10

6

/U). Leukocyte residual in most FFP from 4 blood centers was less than 1×10

6

/U. The home-made plasma filters did not have any adverse impact on the quality of plasma

but their leukocyte reduction effectiveness was limited with a high plasma loss rate.      Conclusion    Compliance to standard plasma preparation procedures makes unnecessary routine leukocyte filtration for FFP. Plasma filtration could be used in some special clinical therapy

such as plasma replacement. The filtration effect of some home-made plasma filters needs to be improved.