Effects of preanalytical factors on hemoglobin measurement: A comparison of two HemoCue® point-of-care analyzers.

BACKGROUND: In field studies, hemoglobin (Hb) is often measured using a battery-operated, portable HemoCue® hemoglobinometer.

METHODS: We compared the performance of 2 HemoCue® models (Hb-201+ and Hb-301) and investigated effects of preanalytical factors on Hb results by simulating unfavorable field conditions.

RESULTS: The Hb-301 produced 2.6% higher results compared to the Hb-201+. Hb had to be measured within 1min of filling the Hb-301 cuvette to avoid artificially elevated concentrations (1.3% per min). The Hb-301 cuvettes withstood elevated temperature (37°C) and humidity (72%) for 3weeks, while the Hb-201+ cuvettes degraded within 10min under those conditions. Both cuvette types withstood elevated temperature for 3weeks. Properly-collected venous and capillary blood produced comparable results. Pooled capillary blood produced comparable results to the second and third but not the fourth drop of blood (3.3% lower). Blood could be stored for ≤4days at 10-30°C before Hb-201+ measurement, but only for 1day at 10-23°C before Hb-301 measurement (≤1% change in Hb).

CONCLUSIONS: Higher Hb results obtained with the Hb-301 may influence the interpretation of anemia prevalence in health surveys. While the Hb-301 performed better in high humidity conditions, the Hb-201+ provided more user flexibility regarding delayed Hb reading.