Healthcare professionals know that the correct selection of a blood collection tube is a fundamental step in the diagnostic process. Each tube color corresponds to specific additives and a designated purpose, directly influencing the accuracy of test results. Using an improper tube can lead to sample rejection or erroneous data, impacting patient care. This guide outlines the common blood collection tube types and their primary applications in clinical settings.
Tubes for Hematology and Coagulation Studies
Two tube types are frequently used for evaluating blood cells and clotting function. The lavender-top tube, containing EDTA (Ethylenediaminetetraacetic acid), is essential for whole blood hematology determinations. These tests include complete blood counts (CBCs) and are also used for blood type verification. For assessing the coagulation system, the light blue-top tube is required. This PT tube uses 3.8% sodium citrate as an anticoagulant in a precise 1:9 ratio with blood. A related variant, the black-top ESR tube, uses a 3.2% sodium citrate solution in a 1:4 ratio, specifically for erythrocyte sedimentation rate testing.
Tubes for Clinical Biochemistry and Immunology
When the required test involves analyzing serum or plasma for chemistry panels, a different set of tubes is employed. The red-top plain tube, which contains no anticoagulant, is designated for collecting samples in clinical biochemistry and immunology. For a more streamlined process, the gold-top GEL tube contains a clot activator and a separating gel. This setup is used for quickly obtaining serum for measurement and various immunology tests. These tubes are workhorses in laboratories processing a high volume of general chemistry profiles.
Specialized Tubes for Metabolic and Anticoagulation Tests
Certain tests require very specific additive properties to preserve the sample’s integrity. The gray-top fluoride tube, for instance, contains potassium oxalate and sodium fluoride. These additives inhibit glycolysis, making this tube type necessary for accurate blood glucose level testing. For tests requiring plasma, the green-top plasma tube is used. It contains lithium heparin or sodium heparin, which prevents clotting. This allows the tube to be used for a range of routine and emergency clinical biochemistry tests, as well as some analyses in hematology.
A clear grasp of blood collection tube protocols is a component of laboratory quality control. The right tube ensures the sample integrity needed for reliable diagnostics. At WEGO Medical, we supply a range of high-quality blood collection tubes designed to meet these precise clinical requirements. Our products are developed to support the exacting standards of modern laboratories, contributing to the dependable workflow that healthcare professionals rely on every day.
