The HemoCue®, a point of care B-hemoglobin photometer, measures hemoglobin concentrations accurately when mixed in vitro with canine plasma and three hemoglobin-based oxygen carriers (HBOC)

Purpose: Accuracy of measurement of low hemoglobin concentrations using the HemoCue(R), a B-hemoglobin photometer (HemoCue AB, Angelholm, Sweden) may exhibit significant variability. Infusion of hemoglobin-based oxygen carriers (HBOC) result in low concentrations of plasma hemoglobin. Our study assessed B-hemoglobin photometer measurement accuracy of three HBOC: (hemoglobin glutamer-200 (bovine; Oxyglobin(R), Biopure Corp., Cambridge, MA,USA); hemoglobin glutamer-250 (bovine; Hemopure(R), Biopure Corp, Cambridge, MA, USA), and hemoglobin-raffimer, (human; Hemolink(TM), Hemosol, Inc., Toronto, Ontario, Canada). Methods: In the laboratory, 45 split canine plasma samples were mixed with hemoglobin glutamer-200 (8.13, 16.25, 32.5 g(.)L(-1) concentrations), 45 samples were mixed with hemoglobin glutamer-250 (8.13, 16.25, 32.5 g(.)L(-1) concentrations), 45 with hemoglobin-raffimer (12.5, 25.0, 50.0 g(.)L(-1) concentrations), and measured. Plasma samples without HBOC served as control. Hemoglobin concentration was determined by a laboratory analyzer (Coulter Corporation, Hiafeah, FL, USA) and B-hemoglobin photometer (HemoCue(R), Angelholm, Sweden). Two independent technicians performed blinded sample measurements and randomly tested each sample five times. Results were analyzed according to Bland and Altman analysis. Results: B-hemoglobin photometer demonstrated high repeatability for all three HBOCs. Repeatability coefficients were 0,37 g(.)L(-1) and 0.48 g(.)L(-1) for hemoglobin glutamer-200, 0.39 g(.)L(-1) and 0.4 g(.)L(-1) for hemoglobin glutamer-250 and 1.07 g(.)L(-1) and 0.85 g(.)L(-1) for hemoglobin-raffimer. An acceptable agreement was found between the B-hemoglobin photometer and the laboratory analyzer for all three HBOCs tested. Conclusion: The B-hemoglobin photometer accurately determined the concentration of three HBOC solutions dissolved in canine plasma.