Request Form 

Combined Pathology Blood form (Yellow/Black or Blue for GP's) or
Microbiology form (Green)

Availability

On request up to 22:00.  Outside normal working hours, the on-call Microbiologist MUST be contacted via the hospital switchboard to request that this test be performed

Specific Criteria

Clotted blood should be collected:
a) Pre-dose immediately prior to the drug being given
b) Post-dose 1 hour after dose
It is acceptable/preferable to send pre- and post-dose samples together, with one request form, but the samples MUST be clearly labelled as pre- or post-dose and with the time of collection

Patient Preparation

Dosage should be 12 hourly preferably arranged for 09:00 and 21:00
First assays should be undertaken on the the third or fourth doses, whichever coincides with the 09:00 dose
Subsequent assays should also be timed to coincide with the 09:00 dose

Turnaround Time

All tests will be performed on the same normal working day, provided that the sample is received in Microbiology by 17:00

If Gentamicin assay is required between 17:00 and 22:00 on weekdays, or at weekends 09:00 - 22:00, please contact the on call Microbiologist via the hospital switchboard

Gentamicin assays are NOT available between 22:00 and 09:00 

Specimen

Serum

Volume

5 ml

Container

Yellow top (SST) tube
For patients on haemodialysis, blood in a green top (Lithium heparin) tube is preferred

Collection

Samples should be transported to laboratory immediately

Lab. Handling

Perform the assay assay soon as possible

Causes for Rejection

Unlabelled sample
Not meeting specific criteria for analysis
Delay in sample reaching laboratory

Reference Range

Pre-dose -    <2.0 mg/L          (multiple dose regime)
                   <0.5 mg/L          (single dose regime)

Post-dose -    6.0 - 10.0 mg/L (multiple dose regime)