Anticoagulant Anticoagulant Is a substance that prevents blood

(Anticoagulant)

(Anticoagulant) • Is a substance that prevents blood from coagulation or clotting. • The most common hematology are: anticoagulants 1. EDTA: Ethylen Diamine Tetraacetic acid 2. Sodium citrate 3. Heparine used in

• EDTA and sodium citrate prevent coagulation by removing calcium which is one of the essential factors in coagulation from the blood by precipitation. • Heparin acts by forming compiler with plasma antithrombin, which inhibits thrombin and other stages of clotting factor activation.

1) EDTA: • Its used in a concentration of 1 to 2 mg/ml of blood • It may be used for both hematology and chemistry tests, and is the preferred anticoagulant for blood cell counts (CBC), ABO Blood grouping.

2) Sodium citrate: • The ratio is one part of 3. 8% aqueous solution to nine parts of whole blood. • Its used for blood coagulation and platelet function studies (PT &PTT) and can be used for Erythrocyte sedimentation rate (ESR).

3) Heparin: • Its concentration is 0. 1 to 0. 2 mg/ml of blood. • Its good for prevention of hemolysis but it is not satisfactory for leukocyte or platelet counts because of cell clumping. Its also produce a trouble some blue background in wrights stain.

Color code tube selection of anticoagulants commonly used Stopper color Additive Notes Red No additive • Used for blood bank, some chemistries. • Collection of serum Lavender (purple) EDTA • 10 -15 min is required to allow blood to clot before centrifugation • Collection of whole blood ( binds calcium)

Color code tube selection of anticoagulants commonly used Stopper color Green Additive Notes Sodium or lithium heparin • Inhibits thrombin activation. • chemistry studies Light blue Sodium citrate • Coagulation studies (bind calcium) (PT &PTT) (ESR).

Color code tube selection of anticoagulants commonly used Stopper color Gray Additive • Sodium fluoride & potassium • For glucose oxalate: inhibits enolase determination in (phosphopyrovate dehydrogenase) • Sodium iodoacetate: inhibits glocose-3 -phosphate dehydrogenase Yellow Notes Acid citrate dextrose (ACD) chemistry (stabilize glucose in plasma) • For use in blood bank studies, HLA phenotyping, DNA and paternity testing (preserves red cells)

• Blood collection: ü Blood sources for hematological tests are venous blood and capillary blood. • 1) venous blood: ü Some tests require a few cubic centimeter of blood. It is obtained from a vein. Vein puncture is usually obtained by drawing specimen of blood from a superficial vein wrist, hand, or ankles.

• 2) capillary blood: ü Some tests may be performed with a few drops of blood, the blood is obtained from the lobe of the ear, finger tips or heal surfaces (in case of infants).

Blood bags

Blood Containers • Blood must be collected into an FDA-approved container that is pyrogen-free and sterile and contains sufficient anticoagulant for the quantity of blood to be collected. • The container label must state the type and amount of anticoagulant and the approximate amount of blood collected. • Blood bags may be supplied in packages containing more than one bag. The manufacturer’s directions should be followed for the length of time unused bags may be stored in packages that have been opened. by Mohammed Abu-basha 13

Blood Collection • Whole blood is collected in clear plastic bags that contain different mixtures of anticoagulants: 1. Citrate: chelate calcium, preventing coagulation 2. Phosphate: prevents p. H from dropping 3. Dextrose: provides nutrients to RBCs during storage 4. Adenine: maintains ATP

Anticoagulants • Anticoagulants: – CPD • Citrate, Phosphate, and Dextrose • 21 day shelf life (at 1 -6°C) – CP 2 D • Citrate, Phosphate, and 2 Xdextrose • 21 day shelf life (at 1 -6°C) – CPDA-1 • Adenine added • 35 day shelf life Ø Additive Solutions prolong red cell survival for 42 days