Anticoagulants and Blood Collection Tubes

Flashcards covering the mechanisms, applications, and tube types for EDTA and Sodium Citrate anticoagulants.

Anticoagulants

Substances that prevent blood from clotting.

EDTA

Ethylenediaminetetraacetic acid, used in concentrations of $1.5\,mg/ml$ of whole blood.

EDTA MOA

Removes ionized calcium ($Ca^{2+}$) through irreversible chelation.

Versene

Disodium $Na_{2} EDTA$ (dry anticoagulant).

Sequestrene

Tripotassium $K_{3} EDTA$ (liquid anticoagulant).

Platelet satellitosis

An occurrence in EDTA anticoagulated whole blood where platelets encircle the periphery of neutrophils, causing falsely low platelet counts.

Platelet satellitosis remedy

Re-collect blood using sodium citrate anticoagulant and multiply the platelet count by $1.1$.

Effects of excess EDTA

Produces shrinkage of RBCs, swelling of platelets, and falsely decreased ESR and low hematocrit readings.

Purple top tube

Contains EDTA; used for routine hematology and HBA1C.

Pink top tube

Contains EDTA; used for blood bank.

Tan top tube

Contains EDTA; used for lead determination.

Royal blue top tube

Contains EDTA; used for trace elements.

White top tube

Contains EDTA; used for molecular testing (PCR testing).

Sodium citrate (Blue top)

Used for coagulation studies in a $3.2\%$ concentration with a blood to anticoagulant ratio of $9:1$.

Sodium citrate (Black top)

Used for the Standard Westergren ESR method in a $3.8\%$ concentration with a blood to anticoagulant ratio of $4:1$.

Plumbism

Another term for lead poisoning.

Gray top tube

Contains sodium fluoride.

Sodium citrate MOA

Binds to calcium to prevent clotting of blood.

Labile coagulation factors

Factor V and VIII, which are preserved by sodium citrate.