Laboratory Haematology &
Transfusion Medicine Intern Orientation Week
25 January 2019
Overview •Patient blood management •Diagnostic haematology
• Diagnostic errors – pre-analytical stage • Blood film morphology reviews • Coagulation studies
•Laboratory haematology consultation service
Patient Blood Management
What do you need to know about transfusion medicine?
Specimen collection • Identification of the patient is paramount!
• Label blood tubes straight after taking the sample • Ensure the right patient’s information is on the blood tube • Incorrect labelling → Wrong blood in tube → Wrong blood
component transfused → Death or further injury to the patient • Zero tolerance for errors
AABB Transfusion Guidelines (2016)
• Red Cells • Consider the haemoglobin level, overall clinical
context and alternatives to transfusion • Variables to consider: rate of decline in Hb, volume
status, symptoms of anaemia (e.g. shortness of breath, chest pain)
• Restrictive RBC transfusion threshold: not indicated until Hb is 70g/L for hospitalised patients
• For those undergoing orthopaedic surgery, cardiac surgery or pre-existing cardiovascular disease: 80g/L
Documentation • Why are you wanting the patient transfused? What product?
Quality improvement
audits
Product reconciliation
Investigating transfusion
related events
To ensure a complete legal
record of patient’s visit
Consent
• NSW Health Policy requires informed consent prior to transfusion of any blood product
• Documented on general ‘Consent for Medical Procedure’ form, or alternate surgical procedure form (for those undergoing surgery)
• Valid for whole admission, or for 12 months for those on long-term treatment plans
• Resources to help with gaining consent on intranet page
Patient Information • Should be provided to
patients / carers when discussing consent
• Available in 15 different languages
• Downloadable on Blood Management Intranet page
** Please note that at Westmead apheresis cryo is used, which is not reflected in the protocol, so the number of units is half the specified (2 instead of 4) as apheresis cryo is twice the volume and twice the fibrinogen content as pooled cryoprecipitate
Diagnostic Haematology
Source of errors in laboratory (haematology) testing
• Analytical issues
Extra-analytical (pre- and post-) issues
Pre-analytical pitfalls lead to erroneous results
• Delays in getting test results • Unnecessary re-draws/re-tests • Increased cost • Decreased patient satisfaction • Incorrect diagnosis/treatments • Morbidity and mortality
Preanalytical issues
• Patient factors • Specimen collection
• Patient identification • Draw technique, appropriate tube and volume • Mixing
• Specimen transportation • Specimen processing
≥ 1 min
Venous stasis
Note on request form if difficult/traumatic collection!
Whole Blood: Cells + Plasma + Anticoagulant
(EDTA)
Whole Blood: Cells + Plasma + Anticoagulant
(Citrate)
↑ coagulation time
Excess citrate
& dilution
Correct Citrate: Plasma
ratio
Coagulation - Citrate (blue top) samples especially susceptible to preanalytical errors
<90% >55%
Mixing
• Insufficient mixing -> microclots • Platelet count, haematocrit, haemoglobin • Coagulation studies
• Low fibrinogen • Shortening of APTT and PT
• Excessive mixing or vigorous inversions • Haemolysis -> sample rejection
FBC & Blood Film Journey
21
Blood film review - Microscopy
Haemostasis testing • Routine coagulation
tests • PT/INR, APTT, TT,
Fibrinogen, D-Dimer • Specialised
haemostasis tests • LMWH (anti-Xa) assay • NOAC quantitative
assays* • Factor assays, factor
inhibitors, VWF, platelet function
• Thrombophilia tests
NOACs and tests of coagulation Coagulation
test Effect of
Anti-Xa NOACs (Rivaroxaban)
Anti-Xa NOACs
(Apixaban)
Anti-IIa NOACs (Dabigatran)
PT/INR ++ (+) +
APTT + (+) ++
TT - - ++
Anti-Xa ++ ++ -
Favaloro et al. Pathology 2011; 43: 682–92 Favaloro & Lippi. Biochemia Medica, 2012;22:329-41 Di Minno et al. Semin Thromb Hemost. 2013;39:840–846
Key contacts Transfusion Lab: • 57644 • Emergencies: 57700 • Senior Scientist: 57650 Laboratory Haematology Specialists: Leo Pasalic: 56352 Elizabeth Tegg: 56352 Laboratory Haematology AT on call: • pg 27150 • 0409 392 151 Jo-Anne Greaves ( Transfusion CNC): • 0427 237 562 • 57580