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Is there a list of specimen collection tubes and their uses?

The following is a list of tubes referred to in Mayo Medical Laboratories' specimen requirements:

Green-Top Tube (Sodium Heparin): This tube contains sodium heparin -- used for collection of heparinized plasma or whole blood for special tests. Note: After tube has been filled with blood, immediately invert tube several times to prevent coagulation.

Grey-Top Tube (Potassium Oxalate/Sodium Fluoride): This tube contains potassium oxalate as an anticoagulant and sodium fluoride as a preservative -- used to preserve glucose in whole blood and for some special chemistry tests. Note: After tube has been filled with blood, immediately invert tube several times to prevent coagulation.

Lavender-Top Tube (EDTA): This tube contains EDTA as an anticoagulant -- used for most hematological procedures. Note: After tube has been filled with blood, immediately invert tube several times to prevent coagulation.

Light Blue-Top Tube (Sodium Citrate): This tube contains sodium citrate as an anticoagulant -- used for drawing blood for coagulation studies. Note: It is imperative that the tube be completely filled. The ratio of blood to anticoagulant is critical for valid prothrombin time results. Immediately after draw, invert tube 6 to 10 times to activate the anticoagulant.

Red-Top Tube: This tube is a plain VACUTAINER® containing no anticoagulant -- used for collection of serum for selected chemistry tests as well as clotted blood for immunohematology.

Royal Blue-Top Tube: There are two types of royal bluetop Monoject® tubes -- one with the anticoagulant EDTA and the other plain. These are used for collection of whole blood or serum for trace element analysis. To determine tube type necessary, refer to individual metals in individual test listings.

Serum Gel Tube: This tube contains a clot activator and serum gel separator -- used for various laboratory tests. Note: Invert tube to activate clotting; let stand for 20 to 30 minutes before centrifuging for 10 minutes. If frozen serum is required, pour off serum into plastic vial and freeze. Do not freeze VACUTAINER(S)®.

Special Collection Tubes: Some tests require specific tubes for proper analysis. To obtain correct tubes for metal analysis or other tests as identified in individual test listings, contact us at 800-533-1710 or 507-266-5700 prior to patient draw.

Yellow-Top Tube (ACD): This tube contains ACD -- used for drawing whole blood for special tests.

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