Additional Test Requesting

Certain tests may be requested to be added on to the original Blood Science order. However, this is dependant upon the following criteria and may not always be possible:

  • type of additional test
  • time period from the original request
  • amount and type of original patient sample
  • requesting location
  • information received
Additional tests are not processed urgently and access to the sample can be limited during busy periods. For tests that are required urgently it is often better to take a new sample and arrange for it to be analysed urgently. If timing is crucial and the test must be done on an earlier sample please discuss this with the duty biochemist or lab staff on call.

Within 24 hours: All analytes except lactate and most Haematology tests

Up to 3 days: Most analytes except CO2, Phenytoin, Valproate and Carbamazepine

Up to 5 days: Most analytes except U/E, Phenytoin, Valproate and Carbamazepine.

5-7 days: Most other tests if the sample is still available.

For Blood Science all requests for additional tests from hospital in-patients and out-patients must be made using a green Add-On Request Form

GPs may request additional testing by contacting the appropriate laboratory by telephone (see Contact Us for contact details)

However all users are kindly requested to keep additional requesting to a minimum, since it can cause significant resource problems for the laboratory.

Failure to provide the laboratory specimen number for which you wish to add tests will delay the processing and may result in the laboratory failing to request the additional work.

All requests for additional tests must be made as soon as possible after the original request was placed. No guarantees can be made that sufficient patient material will be available, especially after 24 hrs.

Microbiology Additional Tests

All microbiology Samples are kept for 7 days after processing, with the exception of CSF samples (kept for 28 days). Any further requests on these tests must be made within this timescale.

NB: Not all samples will be suitable for further testing even within this timescale.