POCT in Haematology

Question 1

What are the benefits of POCT

Answer 1

Speed
Portability
Analyte viability
Convenience
Decreases laboratory workload
Connectivity
Sample quality
Quality assurance

Question 2

What are the risk of POCT

Answer 2

Opportunity for intervention is lost
Once the test is run, the result is out there
Incorrect action can be taken on results
Incorrect interpretation of results
Pre, post and analytical risks
Results may differ from lab tests - trianing needed

Question 3

Give some sites for POTC

Answer 3

ICU
A&E
Operating theatres
Renal dialysis units
Neonatal units
Out-patient departments
Research laboratories
GPs
Independent treatment centres
Pharmacies
In home of patients

Question 4

What is the role of the lab in POCT

Answer 4

• Important that Lab is involved in any POCT system in the Hospital
• Lab acts as back up if POCT out of order
• Performs comparisons between POCT and lab instruments
• Include POCT in EQA systems
• Lab provide appropriate training
• POCT results integrated into Patient electronic record – not written on back of glove or slip of paper!
• POCT should be included in the scope of ISO inspection

Question 5

Write about the updated ISO 15189 to include POTC

Answer 5

The new version of ISO 15189 includes requirements for POCT, which was previously contained in a separate standard, ISO 22870 (which will now be withdrawn).

• Overall, the revisions to the standards focus squarely on patient care, from collecting and processing samples to results reporting.
• The ISO 15189 revisions underline the importance of continually improving quality standards.
• Updated standard is very ‘patient focused’.
• With POCT now integral to this standard, laboratory-supported POCT should be included in the scope of a lab’s quality management system and should follow the requirement of the standard.

Question 6

What are the key recommendations for POCT

Answer 6

• A POCT service should have in place a system for clinical, quality and managerial governance with responsibilities of all participating staff clearly identified
• Only trained and fully competent staff should perform POCT. Training and competency assessment should be on an ongoing basis
• Patient, training, and instrument-related data/records should be maintained and kept as per Data Protection Act 2018, the UKs implementation of GDPR 2018 (UK Government, 2018)
• Samples should be appropriately mixed if taken into a primary tube
• Limitations of POCT should be conveyed to end users through training and competency assessment. The importance of following correct pre-analytical procedures should also be reinforced to end users
• Quality Manual governance should ensure there is an internal and external (where applicable) audit schedule and risk management policy in place
• Where possible, IQC material separate from in-built internal checks should be used
• There should be a clear concise protocol for result interpretation, reflex testing and referral of results and patients for confirmation to a central or satellite laboratory.
• A POCT service should aspire to meet the requirements set out in the relevant ISO standard(s)

Question 7

Give some examples of POCT used

Answer 7

HemoCue for reading haemoglobin

Automated Haematology Analyser by Sysmex

Beckman Coulter analyser

PixCell HemoScreen Blood test analyser

Gene Xpert e.g. Xpert BCR-ABL Ultra

Anticoagulation monitoring

Question 8

What are the benefits of patient self-testing

Answer 8

Improves OAT control

Increases frequency of testing

Intensive education

Patient empowerment

Question 9

What are some user requirement specifications for INR POCT devices

Answer 9

Device must be CE marker
Ability to measure INR 1-8
Must have all elevtical safety features
Calibration and QC features
Storage and retrieval of results
Barcode scanning facilities
Password protected and lockout facilites
Connectivity

Question 10

What are the benefits of POCT for INR

Answer 10

Fast reliable results
Accurate results in one munite
Built in quality control checks every strip automatically
Lab-comparable accuracy
Simple fingerstick test
Improves patient outcomes -> patients who self test have been shown to spend more time in therapeutic range and have less thromboembolic events

Question 11

POCT for DOACs

Answer 11

DOAC dipstick by DOASENSE

Diagnostic urine test strip for qualitative detection of the presence or absence of DOACs

Used in critical care to see if patient has taken DOACs

Question 12

Write about INNOVANCE PFA-200 system

Answer 12

Provides automated assessment for inherited, acquired or drug-induced platelet dysfunction

It measures the process of primary haemostasis and aids in the rapid detection of platelet dysfinction

Question 13

Write about POCT in major haemorrhage

Answer 13

• Coagulation is a dynamic phenomenon, great
  changes in the nature and severity of
  coagulopathy may occur within few minutes in
  bleeding patient undergoing surgery
• Traditional lab tests may come back too slowly
• Treatment given blindly on the basis of “old” lab results often infective, blood products given
  unnecessarily
• Thromboelastometry (TEG), heparin monitoring systems, and platelet function analysers (Multiplate, PFA-100, VerifyNow, etc.) are all very useful.

Question 14

Write about thromboelastography and rotational thromboelastometry

Answer 14

• TEG rotates the cup, and ROTEM rotates the pin
• Real‐time assessment of viscoelastic clot strength in WB
• Liver transplant, cardiac surgery, trauma
• Predict transfusion requirements pre/intra-operatively
• Global picture of haemostatic process and clot dynamics
• Rate of clot formation
• Strength and elasticity of clot
• Quality and stability of clot
• Fibrinolysis/Hypercoagulation