SPECIMEN COLLECTION AND HANDLING
The quality of the information obtained from a laboratory test depends upon the proper collection and handling of
the specimen. Correct patient preparation, specimen collection, packing and transportation are important factors
in obtaining accurate results.
BLOOD COLLECTION TUBES
PLASMA/WHOLE BLOOD
When plasma or whole blood is the required specimen, use one of the tubes listed below. These tubes contain
various anticoagulants which can be identified by the color-coded tube tops. Select the appropriate tube
according to the Specimen Requirement listing under each test.
LIGHT BLUE TOP
Contains buffered citrate solution. Use to collect coagulation studies.
DARK BLUE TOP
Contains sodium EDTA. Use for trace elements.
GREEN TOP - No Gel
Contains sodium heparin. Tube of choice for preparing heparinized plasma or submitting a whole blood
specimen.
GRAY TOP
Contains sodium fluoride and potassium oxalate.
LAVENDER TOP (EDTA)
Contains EDTA (ethylene-diamine-tetra-acetic acid). Use to collect Hematology specimens (CBCs) and Blood
Bank specimens (Type & Antibody Screens).
SERUM
When serum is the required specimen, use one of the collection tubes listed below. Select the appropriate tube
according to the Specimen Requirement listing under each test.
RED TOP
Has no anticoagulant. Use for serum or submitting clotted whole blood. Allow
the blood to clot for 30 minutes, centrifuge the tube
for at least 10 minutes, and
place the serum into a separate plastic vial for transport.
This is the tube of choice for therapeutic drug testing.
When submitting the sample as clotted whole blood, DO NOT separate the serum from the
clot.
GOLD TOP
Serum separator tube. Contains no anticoagulant. Tube of choice for Chemistry testing. Allow
the blood to clot for 30 minutes, centrifuge the tube
for at least 10 minutes after clotting has occurred.
Submit entire tube unless serum is to be frozen.
PLASTIC VIALS
Use when transferring the serum or plasma from the collection tubes. Whenever the specimen is to be frozen,
always transfer the specimen to a plastic vial and place in the freezer or on dry ice.
Serum and plasma specimens should be frozen only if indicated in the Specimen Requirement section. Separate,
label, and freeze the samples as quickly as possible.
Submit a separate frozen sample for each requested test. DO NOT send one frozen sample for several tests.
Constituents that require freezing are sensitive to thawing/refreezing cycles. Repeated thaw/freeze cycles can
produce inaccurate results.
URINE COLLECTION
RANDOM COLLECTIONS
Submit a first morning specimen whenever possible. Avoid any contamination.
Specimens for cultures MUST be collected in a sterile container using the clean
catch, midstream method. Refrigerate immediately.
If a frozen sample is required, freeze immediately after collection.
Always record collection time on the container and request form.
24 HOUR COLLECTION
Proper collection and preservation of 24 hour urine collections are essential for accurate results. Please have the
patient follow these instructions:
Obtain a 24 hour container with the proper preservative from NGMC, or if using your own container, refer to
the Specimen Requirement section for the correct preservative.
Have the patient empty his/her bladder in the morning. Discard this specimen. DO NOT include this sample
in the 24 hour collection.
Have the patient collect the next voiding and add it as soon as possible to the 24 hour container. Add all
subsequent voidings to the container as collected. The last sample collected should be the first specimen
voided the following morning (24 hours after the
previous morning's first void was discarded).
During the collection period, keep the 24 hour container in a refrigerator or cooler
of ice.
Once collection is complete, mix the contents, measure and note the total volume. You may submit the entire
specimen instead.
Pour off the required aliquot (portion)
into a clean screw-top container.
Record the total volume on both the request form and container.
Refrigerate (or freeze if indicated) aliquot until it can be transported to the lab.
SPECIMEN LABELING AND HANDLING
In order to ensure proper specimen identification, please submit all specimens using the following
steps:
Label the specimen vial clearly with patient’s name, collection date and time, and test(s) requested. Proper
labeling protects both you and your patient.
Fill out the request form completely. Make sure all information is complete and accurate.
Place specimen and request form in plastic bag and seal.
Keep a copy of the request form for your records.
STORAGE:
Refrigerate specimen at 4 to
8°C, unless otherwise specified. Keep specimens that should be frozen in the freezer
until courier pickup, at which time it will be placed on dry ice for transport
