In vitro exposure of whole blood to a cannabinoid mixture impairs the quality of red blood cells and platelets.

backgroundIn a recent study, 13.8% of blood donors had reported cannabis use in the 72 hours preceding their donation, and these donors are not deferred under existing criteria in Canada. This high prevalence raises concerns about the potential impact of cannabis use on the quality of blood products. The current study assessed the impact of a cannabinoid mixture on the quality of red blood cells and platelets, from the time of collection and processing to their storage. MATERIALS AND

methodsTo mimic pre-donation cannabis use, whole blood was collected and exposed (in vitro) to varying concentrations (range: 1-24 μg/mL) of a cannabinoid mixture (CM) overnight. Whole blood was then separated into red blood cells (RBCs) and platelets-rich plasma (PRP), which were stored at 4°C (for RBCs) or at room temperature (for PRP). Flow cytometry analyses, hemolysis measurements and biochemical analyses were performed during the processing stage and throughout storage.

resultsIn the RBC fraction, free hemoglobin levels were increased in a dose-dependent manner after the addition of a cannabinoid mixture to whole blood. Hemolysis and methemoglobin levels were significantly higher in CM-exposed RBCs than CM-free controls, after processing and throughout storage. Furthermore, platelet counts and CD62P expression (on day 7 post-separation) were significantly lower in CM-exposed PRP than cannabinoid-free PRP controls. The aggregation potential of CM-exposed platelets was significantly lower than that of cannabinoid-free controls, after the processing and throughout storage. DISCUSSION: An in vitro exposure to a cannabinoid mixture hemolyzed RBCs, impaired oxygen transport by RBCs, reduced platelet counts, and impaired platelet function. These results suggest that pre-donation cannabis use might impair the quality of blood products.