Blood Coating - Edubirdie

University:
The University Of Western Ontario
Course:
Pathology 3500B | Human Pathology
Academic year:

2023
Views:

130

Pages:

2
Author:

Kyuwon J.

● Blood coating ○ Anticoagulant agents preventing clotting of blood samples ○ Applied in FBC bottles + other sample containers ■ Full blood count ■ Prevents clot to from = blood remain in liquid, usable states for analysis ● EDTA ○ Ethylenediaminetraacetic acid ■ Used as anticoagulant coatings in hematology ■ Ca2+ = essential for clotting of cascades = prevention of coagulation ■ Used in Purple-top tubes for CBC/FBC ■ EDTA slides ● RBC shown in pale pink ● EDTA will assist in maintaining size + shapes ● Small purple granules are platelets ○ Clumping could be observed ● WBC ○ Larger darker stained cell ○ Scattered in backgrounds ○ Heparine ■ Enhancement of antithrombin 3 activity ● Inhibition of thrombin + factor Xa ■ Used in greentop tubes for CBC/FBC ○ Citrate ■ Binds with calcium (reversibly) ● Coagulation studies ● Blue top tests ● Clotting preservations for PT, aPTT tests ○ Oxalate + Fluorides ■ Oxalate ● Prevention of coagulation of precipitating calcium ■ Fluorides ● Inhibition of glycolysis ■ Gray top tubes Clinical relevance ● Laboratory testings ○ Coatings are selected on which type the blood test in running ● Prevention of clotting ○ For accurate measurements of blood components ● Patient cares ○ Tube type error may result in inaccurate lab results ○ Misdiagnosis ○ Treatment errors Tube Cap Color Anticoagulant Mechanism of Action Common Tests Purple / Lavender EDTA (Ethylenediaminetetraacetic acid) Chelates Ca²⁺ → prevents clotting CBC (Complete Blood Count), ESR, Blood film, Reticulocyte count Blue Sodium Citrate Binds Ca²⁺ reversibly → preserves clotting factors Coagulation studies: PT, aPTT, D-dimer, INR Green Heparin (Lithium or Sodium Heparin) Activates antithrombin III → inhibits thrombin & factor Xa Plasma biochemistry, Cardiac enzymes, Ammonia, Lactate Gray Fluoride + Oxalate Oxalate precipitates Ca²⁺ (anticoagulant) + Fluoride inhibits glycolysis Glucose, Lactate, Blood alcohol level Red / Gold (SST) No anticoagulant / Clot activator Allows blood to clot → serum separation Serology, Chemistry panels, Hormone assays