Page 179 - Registrar Orientation Manual 2016

Reference:
Effective date:
2015
Expiry date:
2018
Page:
5 of 28
Title: Laboratory Testing Guidelines (DRAFT)
Type:
Clinical Guideline
Version:
01
Authorising initials:
Common Tests and Repeat Testing
The ‘Choosing Wisely’ recommendations are shown in red.
DHB Shared Services Laboratory Test Referral Guidelines recommendations are in green.
Where there is no ‘Choosing Wisely’ or Shared Services recommendation or more details are needed we have made comments in black font and specific recommendations in bold black
We have grouped the tests under departments (Haematology, Biochemistry, Immunology and Microbiology) and in each section we have listed the tests in alphabetical order.
Haematology
Blood count (Cost approximatey $9)
A CBC is the single most costly test performed in Waikato. Nearly 200,000 tests are done every year, costing almost $2 million a year. Many tests are repeated unneccessarily.
The Choosing Wisely recommendations include the following relevant general recommendations which will apply to CBCs:
Don’t do regular tests but test in response to clinical questions.
Don’t do repeat tests if clinically stable; repeat only when clinically indicated.
Do not repeat laboratory tests for patients transferred into the ED who have laboratory results within reference ranges available from outside hospital.
Don’t do screening tests in low risk patients undergoing low risk surgery.
B12 and Folate ($5)
These are commonly requested and repeated without good clinical indications. We recommend:
Do not do B12 and folate unless there is a suspicion of deficiency or malabsorption, for example peripheral neuropathy or macrocytic anaemia, or in unexplained dementia.
Coagulation screen ($10)
The Choosing Wisely recommendations include the following:
Avoid coagulation studies unless there is a clearly defined specific clinical indication, such as for monitoring of anticoagulants, in patients with suspected severe liver disease or coagulopathy.
Cross- match ($54)
Blood is a precious and expensive product. Many patients who have a cross-match never get
transfused so blood is wasted. Unneccessary blood transfusions are common. We recommend:
Do not do a cross match unless the patient is going to be given blood for active bleeding and/or very likely to require an urgent blood transfusion.
Do not ‘order 2 if one will do’.
D-dimer ($28)
D-dimer has limited specificity and will be positive in many hospitalised patients without VTE.
We recommend that testing should be restricted to those patients with a high enough clinical suspicion of VTE to merit further investigation, not to rule out the remote possibility of VTE:
Do a D-dimer only in patients with low to intermediate probability VTE (DVT/PE) where there is a high enough suspicion to justify further investigation for VTE by imaging.
Do not do a D-dimer in post-operative patients.