Results can be adversely affected by a number of factors which can lead to a delay in blood product provision or a request being denied and a repeat sample being requested.
Common problems affecting results and causing a delay in testing and blood allocation are listed below.
Request Card/Sample Labelling Errors
The laboratory operates a zero tolerance policy on request form and sample labelling. The patients Blackpool Victoria Hospital number, surname, forename, date of birth must be clearly hand written on the sample tube. The laboratory does not accept samples labelled with printed stickers. Please do not use pens which smudge easily such as gel pens. The sample must be signed by the collector with the date and time of collection clearly detailed.
The request form should also be correctly completed and exactly match the patient identification details on the sample. The use of patient addressograph labels is encouraged on the request card. This can help minimise the risk of errors. Always check the label used and ensure that details have not been cut off.
The person taking the sample must also complete the ID Verification Box (bottom left on request form), printing their name, signing and writing the date/time the sample was taken.
The request form should be signed by a requesting Doctor/practitioner, and any blood product/batch product requests clearly stated.
Sample Contamination
Contamination may occur when taking samples from a line arm, or when taking multiple blood samples in the incorrect order. Different sample tubes contain different preservatives or anticoagulants, therefore the Trust Venepuncture procedure must be closely followed.
Ensure thorough and instant mixing of blood with anticoagulant and NEVER transfer blood from one bottle to another.
Sample transport delay
Delays in sending sample to the laboratory can cause erroneous results in some tests.
Haemolysed samples
Haemolysed samples can cause problems when performing testing on the analysers therefore care should be taken when undertaking venepuncture to minimise chances of sample haemolysis.
Clotted samples
Clotted samples cannot be processed. Care must be taken when taking samples from patients that are difficult to bleed, as clot formation may occur within the sample.
Monoclonal antibody therapy
Monoclonal antibody medications such as Daratumumab and Isatuximab cause interference with antibody screen results and the ability to successfully crossmatch and provide compatible red cells.
Patients will require crossmatching at NHSBT. Please give maximum notice if blood products are required and contact the laboratory for further information.
