Specimen collection
Details of the type and volume of specimen required for particular assays are given in the appropriate sections and are summarised in the table "Specimen Requirements". Small specimens from young children or neonates can be analysed, but the range of tests and sensitivity of detection may be limited. Some assays are prone to interference from materials in certain types of blood and urine specimen container. The use of blood tubes with 'gel' separators should always be avoided. The use of preservatives such as boric acid should also be avoided. If in doubt please contact the laboratory for further advice.
TUBE TYPES v CAP COLOURS
| Tube Type | Cap colour |
| Fluoride Oxalate | Yellow |
| Lithium Heparin | Orange |
| EDTA | Red |
| Plain (Clotted) - no gel | White |
| Sodium Citrate | Green |
Request forms
Assay request forms are available from the Laboratory. A completed request form must accompany each specimen or batch of specimens. Please ensure that the patient's name, date of birth, location and requesting doctor's name are legible. A telephone number is essential for reporting urgent results. All patient requests must be authorised by a registered medical practitioner.
Specimen packaging
Screw all specimen container tops on firmly, wrap the specimen in absorbent wadding to absorb any fluid leakage, and place in a self-sealing plastic bag. Insert the request form and any other paperwork into the secondary pocket of the specimen bag. Please make clear any serious infection hazards which may be associated with the specimens.
Pack specimens in either a strong cardboard box with a full depth lid or a grooved polystyrene box and seal with self-adhesive tape. Avoid using padded envelopes. NEVER USE STAPLES TO SEAL ANY PACKAGE CONTAINING CLINICAL SPECIMENS.
Specimen Storage (Prior to Despatch)
If specimens need to stored prior to despatch to the laboratory:
Urine samples can be stored either frozen or at +4oC. If they are frozen, they should not be unfrozen until despatch to the laboratory.
Blood samples should be kept at +4oC.
Serum & plasma samples can be stored either frozen or at +4oC. If they are frozen, they should not be unfrozen until despatch to the laboratory.
Transport
All "routine" requests should be sent by first-class post or hospital transport. Urgent requests within normal laboratory hours (08.30 - 17.30) should be delivered by taxi or courier service directly to the laboratory.
Out-of-hours urgent specimens should be delivered to the West Midlands Poisons Unit (Ward D8) in the City Hospital.
NOTE:
Please telephone before sending urgent requests.
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Assay Availability & Specimen Requirements