My lab is collecting PMNs and we wish to calculated the donor RBC loss. Our counter gets fooled by the high WBC concentration and gives incorrect HCTs. I've found in the manual a means to adjust the HCT using the following: Adjusted Collect Hematocrit = ([RBC] - ([WBC]/1000) x MCV) / 10 Does anyone use this equation? Has anyone validated it and how? Thanks!