Comparison of small-volume tubes with vacuum blood tubes for complete blood count

Abstract

Comparison of small-volume tubes and vacuum blood tubes for complete blood count T he complete blood count (CBC) is one of the most commonly requested clinical laboratory tests [1]. Accurate measurement of the CBC is essential for the correct diagnosis, treatment, and follow-up of patients with hematological disorders. These measurements are now almost fully automated, and the right interpretation of the clinical significance of the results requires knowledge of the pre-analytical phases [2]. The blood collection tubes used for a CBC should contain anticoagulant ethylenediaminetetraacetic acid (EDTA), according to the recommendation of the Clinical & Laboratory Standards Institute (CLSI) [3]. EDTA salts are used for the anticoagulation of whole blood for hematological analyses because the cellular components of the blood are well preserved by EDTA [4]. Today, a CBC is typically performed with whole blood collected in tubes containing dipotassium EDTA (K2EDTA) as an anticoagulant. Blood collection tube additives and components are an important component of the pre-analytical phase in terms of a potential influence on laboratory test results. Although Objectives: A complete blood count (CBC) is one of the most commonly requested clinical laboratory tests. Vacuum blood tubes are used routinely, and now, new small-volume tubes (SVTs) containing dipotassium ethylenediaminetetraacetic acid (K2EDTA) are also in use. The aim of this research was to compare SVTs with vacuum blood tubes for use in a CBC. Methods: Venous blood samples were taken from 40 healthy volunteers and were collected in BD Vacutainer (Becton, Dickinson and Company, Franklin Lakes, NJ, USA) K2EDTA tubes and BD Microtainer (Becton, Dickinson and Company, Franklin Lakes, NJ, USA) K2EDTA tubes. CBC parameters were analyzed using an ABX Pentra DF 120 device (Horiba, Ltd., Kyoto, Japan). Results: Red blood cells (RBC), hemoglobin (HGB), hematocrit (HCT), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and basophil (BASO) levels were found to be statistically significantly higher, while platelet (PLT) levels were determined to be statistically significantly lower in the SVT analyses compared with those of the vacuum blood tubes. When the percentage difference was compared with the total allowable error, RBC, HGB, HCT, MCH, MCHC, red cell distribution width, white blood cell count, neutrophil, lymphocyte, monocyte, eosinophil, and BASO values demonstrated a general trend of positive bias, while PLT values demonstrated a general trend of negative bias on a Bland-Altman bias plot. Conclusion: The results of this study demonstrated that venous blood samples from SVTs generated a significant bias in the CBC results. In addition, clotted samples were observed more frequently among those collected in SVTs in this study. The design of SVTs may have an important and detrimental effect on the accuracy and efficacy of the results of a CBC.

Incomplete filling of spray-dried K2EDTA evacuated blood tubes: impact on measuring routine hematological parameters on Sysmex XN-10

“…The problem of blood tube underfilling has received much less attention in the area of hematological testing, wherein there is widespread perception that a perturbation of the ratio between whole blood and the reference anticoagulant for hematological testing (i.e., dipotassium ethylenediamine tetraacetic acid; K2EDTA) (4), may not generate clinically significant bias in most tests results. Thus, although small volume blood tubes have now become available in the market for pediatric blood collection and for reducing diagnostic blood loss (especially in anemic and critical patients), they were found to display a clinically significant bias compared to standard volume tubes for hemostasis assays (5), and also for hematological testing, with the bias of hemoglobin, hematocrit and red blood cell (RBC) values exceeding 14%, or with values becoming even lower than 10% for the platelet count (6).…”