Comparison of Copper (II) Sulphate to Hemocue Analyser in the Estimation of Haemoglobin among Voluntary and Replacement Blood Donors at Bugando Medical Centre

Abstract

Background Pre-donation haemoglobin (Hb) screening is among the foremost test done on blood donors to determine whether an individual is fit to donate with the intention of preventing inadvertent donation from an anaemic donor. The National Blood Transfusion Service (NBTS) in Tanzania uses the Copper II Sulphate (CuSO4) gravimetric method to estimate haemoglobin (Hb) in blood donors. The accuracy of the copper II sulphate method for the rapid screening of prospective blood donors has been questioned because this rapid screening method may lead to false deferral of truly eligible prospective blood donors. However, this and other point-of-care method may provide false results. Methods This was a cross-sectional study conducted among 236 eligible blood donors attending BMC transfusion centre at Mwanza, Tanzania. The blood donors were asked for their consent to participate in this study from 1st May to 1st August 2024. Capillary blood samples were obtained for Hb estimation by CuSO4 and HemoCue methods, and 3mls of venous blood were also collected for Hb quantification by AHA (gold standard). Descriptive statistics were used to analyse the demographic details of the donor. Kappa statistics were used to determine the level of agreement between the two methods of Hb estimation. Results The median age of the study participants was 30 years (IQR: 25-36). The proportion of false eligible donors was 5.5%, and false deferral donors were 2.3% using the CuSO4 gravimetric method. The specificity, sensitivity, positive and negative predictive values, and Kappa agreement for CuSO4 were 53.8%, 94.7%, 93.8%, 58.3%, and 0.51, respectively. In contrast, the specificity, sensitivity, positive and negative predictive values, and Kappa agreement for HemoCue were 63.6%, 97.9%, 96%, 77.7%, and 0.67, respectively. Conclusion. The current study revealed that, the performance of the CuSO4 gravimetric method is relatively poor, with a high proportion of false eligible donors than the HemoCue method. These findings warrant further studies to evaluate the quality control measures for CuSO4 gravimetric method and explore alternative point-of-care methods for Hb estimation among blood donors in similar resource limited-settings.