The effect of haemolysis on blood glucose meter measurement

A study was performed to assess the effect of varying degrees of sample haemolysis on the measurement of blood glucose by the Accutrend, Companion 2, ExacTech, Glucometer II, Glucometer 4, One Touch II, and Reflolux II blood glucose meters. Fresh venous blood was sonicated to induce complete haemolysis and then added in increasing proportions to homologous untreated blood to obtain nine samples with free haemoglobin concentrations up to 50 g l-1. The Accutrend meter showed the only significant (p < 0.05) linear relationship to degree of haemolysis (r = 0.988, p < 0.0001). For every 7% of red cells lysed, the Accutrend value increased by 15%. All other meters gave results which were within 15% of the non-haemolysed value. However, extreme (100%) haemolysis not only affected the Accutrend (glucose value 108% greater than reference) but also the ExacTech (+98%), the Glucometer II (-32%), and the Companion 2 (-41%). Thus, unwitting use of a haemolysed sample to measure whole blood glucose may, with the Accutrend in particular, lead to erroneous results.