PHLEBOTOMY

      Purple or lavender: EDTA is a strong anticoagulant; purple tubes are used for complete blood counts or blood smear preparation i.e. where whole blood is required.

      Phlebotomy is a procedure that removes blood from the body. Regular phlebotomy treats people who have too much iron in their blood, such as with hemochromatosis, or who are producing too many red blood cells, such as with polycythemia. Removing blood regularly decreases iron levels in the body by reducing the number of iron-rich red blood cells.

      Health professionals perform phlebotomy in a medical clinic. The process is similar to donating blood. A health professional inserts a needle into a vein in your arm and removes about 500 mL (17 fl oz) of blood. The procedure takes about 30 minutes. You do not need to fast or make special preparations before phlebotomy. But try to eat a good meal and drink plenty of fluids before phlebotomy. This will prevent dizziness or fainting.

      Health professionals will have you sit or lie down. During the procedure, they monitor your blood pressure and pulse.

      Phlebotomy- Meaning of Color Coded Top for Tubes

      The meanings of the different colors are standardized across manufacturers. Gold or ‘Tiger’ Red/Black top: No additive, Serum Separator tube (SST) Clot activator and gel for serum separation on centrifugation. Used in chemistry, immunology and serology. Orange or Grey/Yellow ‘Tiger’ Top: Contain Thrombin, a rapid clot activator, for STAT serum chemistry testing.

      Green: Plasma determinations of lithium level use sodium heparin and for ammonia levels sodium or lithium heparin is used. Contains Sodium Heparin or Lithium Heparin as anticoagulants. Light Green or Green/Gray Tiger: Blood chemistry determination uses this additive when plasma is used for analysis. PST gel separates plasma at the bottom of the tube.

      These tubes contain potassium salt of EDTA, which forms calcium salts to remove calcium. Purple tubes are useful for blood type and screening. These tubes require full volume and proper mixing 6-8 times to prevent platelet clumping. Grey: Sodium fluoride inhibits enzymes so substrate glucose is not metabolized; Potassium oxalate is added as an anticoagulant. These tubes require full draw for blood glucose determination.

      Light blue: These tubes are used for coagulation assays since they contain citrate which is a reversible anticoagulant. Proper dilution factor is attained by filling the tube full since liquid citrate dilutes the blood. Dark Blue: Anticoagulant sodium heparin is present or EDTA or no additive. These tubes are used for toxicology and trace metal analysis. Pink: Blood banking and Molecular/viral load testing application. Similar to purple tubes in that it also contains EDTA.