In vitro alteration of hematological parameters and blood viscosity by the perfluorocarbon: Oxycyte

While perfluorocarbons (PFCs) may be useful in some clinical situations, previous studies have shown that interferences with chemistry analytes can occur with blood samples containing PFCs. This in vitro study focused on how the PFC Oxycyte may affect hematology measurements in blood samples. Swine blood diluted with Oxycyte or saline (Controls) were analyzed for Hemoglobin (Hb), Mean Corpuscular Volume (MCV),Hematocrit (Hct) and Fluorocrit (Fct) using a HemaVet, ABL-735 (ABL), or microhematocrit. Ancillary tests (blood viscosity, electrolytes, cell counts, and red blood cell morphology) were performed secondarily. Increasing Oxycyte resulted in increases in MCV, Hct, and visible cell shape change and morphology vs. Controls. Effects correlated with lower sodium in Oxycyte samples vs. Controls. With increasing Oxycyte, Hb became higher than Controls or became unpredictable depending on the instrument (HemaVet or ABL, respectively). Fct was smaller than predicted and likely represented the heaviest components of Oxycyte. At ≥50 % Oxycyte, RBC hemolysis rendered further measurements impractical. Viscosity first increased then decreased with increasing Oxycyte, peaking at ~40 % Oxycyte. Hct, MCV, Hb, and RBC morphology may be affected by Oxycyte. These observations correlated with lower sodium and increasing Oxycyte, causing hemolysis at high Oxycyte concentrations. These changes were due to alterations in the blood samples in vitro and this should be considered when interpreting hematology parameters from in vivo studies.