General requirements for specimen collection are provided below and should be adhered to in order to prevent specimen rejection . For accurate, quality testing and results, correct collection, labeling and handling are essential. Improperly collected specimens are the leading cause of clinically inaccurate results or resulting delay. Refer to the Directory of Services for correct tube color, minimum draw volumes, handling, and shipment instructions.
- Specimens collected in mint green top tubes do not require clot time. They should be gently inverted 8-10 times to mix then centrifuged for 10-15 minutes. Centrifuging must be done within 2 hours of collection.
- Specimens collected in gold top tubes must be allowed to clot (30 minutes) then centrifuged for 10-15 minutes. Incomplete clot formation will result in incomplete separation of the specimen and cause clots and cells remaining in the serum. Incomplete specimen separation may jeopardize the quality of results or cause the specimen to be rejected. Centrifuging must be done within 2 hours of collection.
- Specimens collected in light blue or lavender top tubes contain additives for inhibiting coagulation. Immediately following the blood draw, gently invert the tube 8-10 for lavender and 3-4 times for light blue, to ensure mixing of additive.
- Urine specimens are to be submitted 1 aliquot per test requested. For tests requiring 24 hour collection, indicate urine volume on both the specimen container and requisition form.
- Refer to the Swab Chart (PDF - 588.1 KB) for questions on which swab to use
- Refer to the Stool Collection Chart (PDF - 44.0 KB) for collection instructions on stool samples
- Be sure all specimen containers are labeled with both the patient’s first and last name, and date of birth.
- Segregate specimens as to frozen, refrigerated or room temperature.
Order of Tube Draw
Below is the order of draw for tubes, additives in the tubes, and a brief description of common uses. The order in which tubes are drawn is important and should be followed to prevent cross-contamination of additives/anticoagulants:
|Tube color||Additive||Common use|
|Blood culture bottle||Usually drawn first because of sterile technique|
|Light blue top||Sodium citrate||Coagulation tests (Prothrombin time, Thrombin time, etc.)|
|Plain red top||No additive||Serum|
|Gold top (SST)||No additive||Serum, tube inversions mix blood and clot activator|
|Dark green top||Sodium heparin||Chromosome testing|
|Mint green top||Lithium heparin||Plasma, tube inversions prevent clotting|
|Lavender top||EDTA||Used for whole blood in Hematology|
|Pink top||EDTA||Blood bank for type and cross-match|
|Royal blue top (PDF - 310.3 KB)||EDTA||Trace element determinations, heavy metals|
|Tan top||EDTA||Lead determinators|
|Gray top||Potassium oxalate or Sodium fluoride||Glucose screening|
Please refer to the Directory of Services or the Epic Procedure Catalog for test specifics such as tube color and amounts to draw. The above list is only a partial list of common tube colors and is intended to be used as a guide for the draw order.