Method Comparison and Investigation of Interference Variables of a Hand-Held Hemoglobinometer(HemoCue Hb 201) in Cats.

Abstract

BACKGROUND: Regular blood sampling to monitor RBC mass in anemic cats can exacerbate anemia. Laboratory-based reporting can delay clinical decisions. A hand-held hemoglobinometer, HemoCue Hb 201(HC-201), requires only one drop of blood (10 μL) and provides results within 1 min. OBJECTIVES: This preliminary study aimed to evaluate the utility of HC-201 in cats and investigate the impact of potential interferents on its performance. METHODS: One hundred and fifty-four venous blood samples in EDTA from 93 cats were analyzed. Hemoglobin concentration was measured once using an ADVIA 2120 analyzer and compared to the mean of 2-3 replicate measurements from an HC-201. Agreement and systematic bias between HC-201 and ADVIA results, along with precision between HC-201 replicates, were assessed using Lin's concordance correlation coefficient, non-parametric Bland-Altman, Passing-Bablok regression, and intraclass correlation coefficient. The performance of HC-201 in the presence of anemia, leukocytosis, azotemia, lipemia, icterus, hemolysis, and peripheral versus jugular venipunctures was assessed using Wilcoxon rank-sum tests. RESULTS: Passing-Bablok analysis revealed a significant constant bias (intercept = -2.242, 95% CI: -4.042 to -0.667) but no significant proportional bias (slope = 1.015, 95% CI: 1.000-1.032). HC-201 demonstrated excellent agreement (ρ = 0.989) and precision (ICC = 0.997) with a median bias of -0.67 g/L (p = 0.001). The total observed error was 3.02%, within the allowable limits defined by international standards. Neither anemia, leukocytosis, azotemia, lipemia, nor venipuncture site influenced HC-201 measurements. Samples with icterus and hemolysis were insufficient in number for statistical comparison. CONCLUSIONS: This preliminary study indicates that HC-201 offers reliable point-of-care monitoring for hemoglobin concentration in cats.