Background: Several studies have shown that various anticoagulants used for collection of blood samples produce varying effects on haematological analyses. Tripotassium ethylenediamine tetra-acetic acid (K3EDTA), sodium citrate and lithium heparin remain the most used anticoagulants employed in hematological analysis. There is paucity of data on the effect of these anticoagulants on haematological parameters in humans in Ghana. We assessed the suitability of K3EDTA, sodium citrate and lithium heparin for routine Full Blood Count (FBC) investigation.
Method: A laboratory-based analytical cross-sectional study was conducted using blood samples from 55 conveniently sampled apparently healthy tertiary students from January 2021 to October 2021. Blood samples were taken from each participant into 3 anticoagulant tubes: K3EDTA, sodium citrate and lithium heparin and FBC parameters estimated using the Mindray automated haematology analyzer. One-way ANOVA Kruskal-Wallis test, Mann-Whitney U, Intra-class correlation coefficient (ICC) analysis, Bland-Altman's plot and Lin's concordance correlation coefficient were used where appropriate to ascertain the level of variation, consistency, and agreements among and between results. Normality testing using Shapiro-Wilk test statistic revealed non-Gaussian distribution of data, hence, were presented as median, minimum, and maximum. Data generated were analyzed using STATA v15 and MedCalc v20 where appropriate for statistical analysis. P-values <0.05 were considered statistically significant.
Results: The study comprised 34 males and 21 females. The median age for males (23 years: min = 20, max = 34) was statistically comparable (p = 0.2652) to that of females (22 years: min = 18, max = 34). We observed excellent consistency in the estimation of MCV (ICC = 0.94), MCH (ICC = 0.98), MCHC (ICC = 0.91), GRAN# (ICC = 0.92) and LYMPH% (ICC = 0.91) across the three anticoagulants. Heparin and K3EDTA largely agreed on most of the FBC parameters, 50.0% (7/14) including HGB, MCV, MCH, PLT, LYMPH#, GRAN# and GRAN%. Meanwhile using K3EDTA as a standard, heparin produced almost perfect agreement only in the assessment of RBC (CCC = 0.992) while a substantial agreement was observed in the assessment of HGB (0.971), HCT (0.958) and MCH (0.987). Citrate agreed substantially with K3EDTA in the assessment of LYMPH% (CCC = 0.964) and moderately in the assessment of MCV (CCC = 0.948) and MCH (0.913). Overall, compared to K3EDTA, heparin was highly precise and accurate in the estimation of HGB, RBC, HCT and MCH while citrate determined MCV and MCH more accurately and precisely.
Conclusion: Citrated blood consistently produced lower FBC values compared to heparin and K3EDTA and hence suggests not reliable in the assessment of FBC among humans. Heparin agreed largely with K3EDTA in the estimation of FBC parameters and may be used as a better alternative anticoagulant in the absence of K3EDTA however with great caution.
Keywords: Anticoagulant; Ethylenediamine tetra-acetic acid; Full blood fount; Haematological; Lithium heparin; Sodium citrate.
© 2023 The Authors.