Labeling
Blood
Frozen Samples
Plasma
Serum
Urine
Labeling of Samples
All specimens must be clearly labeled with the patient's identification (first and last name and identification number), date and time drawn/collected, and initials of phlebotomist/collector. Samples inadequately labeled will be rejected for testing and floor/physician promptly notified. If the sample submitted is one which cannot be recollected (i.e. ventricular or spinal fluid, FNA from difficult site, patient no longer available, etc.), the sample may be tested, but the report will bear a notation as to the inadequate labeling of the sample. There may be a delay in the testing. Blood samples for compatibility testing will be rejected if the request form and firmly attached label does not bear the recipient's first and last names, identification number and the date of sample collection. Samples accompanied by request forms which are incomplete, inaccurate, or illegible will not be accepted for testing.
When whole blood is requested, draw the full amount into the Vacutainer tube as indicated by the specimen requirements. This is necessary for the proper blood: anticoagulant dilution. Lavender top (L), green top (Gn), and blue top (B1) as well as other tubes contain preservatives and/or anticoagulants. Gently mix blood by immediately inverting these tubes 10-12 times. Do not shake the tube as this may produce hemolysis.
Top ^ Frozen Specimens
Some specimens must be submitted in the frozen state because of limited stability of the component to be assayed. Keep frozen specimens separate from others, tag them with the frozen specimen stickers and, whenever possible, inform our service representative to keep these specimens on dry ice.
Draw sufficient blood into the proper Vacutainer tube. Mix the specimen by immediately inverting the tube 10-12 times. Separate plasma from cells within one hour by centrifugation if indicated by specific test procedures elsewhere in this booklet.
Draw sufficient blood to yield the necessary serum volume. Use a plain red top or red top separator gel tube (e.g., "CORVAC," "SST," etc.). If a gel tube is used, mix the blood by gently inverting the tube six times. Do not shake the blood. Allow blood to clot at room temperature for 25 to 30 minutes. Without removing the stopper, centrifuge the tube for 20 to 25 minutes. Make sure that the gel has formed a thick, solid, intact barrier between the serum and the clotted cells. If gel trails into bottom of tube, recentrifuge the tube. If using a plain red top tube, transfer serum to appropriate transfer tube. Avoid hemolysis. Certain determinations will be invalidated by hemolysis, particularly glucose, some enzymes, potassium and phosphorus.
IMPORTANT:
Always draw a serum collection (red top) tube before any other tubes. This prevents any carryover of anticoagulants to the serum tube.
For random urine specimens, the patient should collect a portion of urine in a clean vessel. When the volume required is 25 to 100 mL, simply use the aliquot bottles furnished by the laboratory.
For many quantitative assays in which urine is employed, a 24-hour collection is required. Unless otherwise directed by the physician, request the patient to drink less liquid than usual and abstain from alcoholic beverages. Give the patient the appropriate 24-hour urine container as indicated by the specimen requirement. Instruct the patient to discard the first urine voided upon awakening in the morning, and thereafter to save all urine specimens in the 24-hour container including the first morning voiding of the following day. Measure the 24-hour volume and record on both the container and the test request form. Suggestion: Have the patient collect the urine in a clean wide-mouth bottle, and immediately transfer each portion to the 24-hour container. |
