The first step in performing a mixing study is the creation of a 1:1 mix of patient plasma and pooled normal plasma.
It is important to ensure that the pooled normal plasma that the laboratory uses has normal coagulation factor levels before beginning the mixing study; often manufacturers will supply this information.
The creation of the mix can be achieved by aliquoting equal parts of patient plasma to pooled normal plasma. The sample must be mixed by gentle inversion, or by using a pipette to slowly pipette the mixture up and down. This ensures proper incorporation of the factors in the sample.