2 Tube Colors and Additives Free Online FlashCards

Why can’t tube color alone determine a tube’s contents?

Tube colors are clues, not guarantees: additives and uses can vary by manufacturer, facility, and test. Check the tube label and current laboratory instructions.

What is a light-blue tube commonly used for?

Light-blue tubes typically contain sodium citrate and produce citrated plasma for coagulation tests such as PT/INR and aPTT.

Which additive and common tests are associated with lavender-top tubes?

Lavender or purple tubes commonly contain EDTA and are used for whole-blood hematology tests such as CBC; many laboratories also use them for HbA1c.

What is a common use for a pink-top tube?

Pink tubes commonly contain a blood-bank-specific EDTA formulation and are used for testing such as type and screen.

What is the purpose of the glycolysis inhibitor in a gray-top tube?

Gray tubes commonly contain sodium fluoride with potassium oxalate, or another glycolysis-inhibiting formulation. They are used for glucose and selected tests requiring glycolysis inhibition.

What do gold or tiger-top SST tubes contain?

Gold or tiger-top SST tubes contain a clot activator and gel separator and commonly produce serum for chemistry and serology tests.

What is the purpose of blood culture bottles or yellow SPS tubes?

Yellow-top blood culture bottles may contain sodium polyanethol sulfonate (SPS) and collect whole blood in culture medium to detect bloodstream infection.

What additive and specialized uses are associated with yellow ACD tubes?

Yellow ACD tubes contain acid citrate dextrose and are used for selected specialized tests, such as certain cellular or genetic studies.

What should you verify before using a royal-blue tube for trace-element testing?

Royal-blue tubes may be plain, EDTA, or heparin. They are often designed to minimize trace-element contamination, so use the exact tube specified for the test.

What is serum?

Serum is the liquid portion collected after blood clots.

What is plasma?

Plasma is the liquid portion of anticoagulated blood after the cells are separated.

What is the usual order of draw for common blood collection tubes?

The usual sequence is sterile blood cultures, light blue, serum tubes, green, lavender/purple or pink, then gray. Follow the facility’s approved procedure, especially for specialty tubes.