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Safe Anticoagulation Management using Point of Care Dr. Tony Avades Sr. Consultant and Head of Chemistry, Endocrinology and POCT Sections DLMP Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Point of Care testing (POCT) • Tests that are performed at the bedside ..near patient.. physician office = Point of care. • All diagnostic tests evolved from Point of care • Example is urine test at the bedside> moved to>>side room>>moved inside the lab Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section POCT Technology • New technological innovation is delivering – Improved – Simple – Shorter analysis time – Smaller Devices • Laboratory concerns – Non-lab personnel carrying out lab work – Quality Assurance – Encroaching on the lab territory Department of Laboratory Medicine & Pathology 3 Point of Care Testing (POCT) Section Evolution of healthcare and laboratory medicine Home Doctors clinic Future for health care provider and POCT Hospital Reversal of Centralization, since centralization can lengthen the diagnostic decision But more economically from the lab standard 4 Doctor ↔ Patient Prepare request form Record result in EMR Transmit result Phlebotomy Report result Sample transport Validate result Register sample Prepare sample Quality control Analyze sample 5 Point of Care Testing • POCT tests designed to be used at or near the site where the patient is located, that do not require permanent dedicated space, are performed outside the physical facilities of the clinical laboratories and that is performed by non-laboratory personnel. College of American Pathologists (CAP) Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section POCT HMC Policy 7211 • The policy is formulated for all Hamad Medical Corporation services and staff for the establishment of a safe and functional POCT program. • It is for all laboratory tests approved by the POCT Coordinating and Steering Committee. The availability of the result within minutes of asking the clinical question improves the outcome BUT have to ensure safety and quality Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Defining Risk for POCT • Risk is the chance of suffering harm / error and it can be estimated from the probability of the event and the severity of the harm. • Safe POCT is achieved by application of the approved policy, procedures and practices to the task of analysing, evaluation, controlling and monitoring risk. • Risk management of POCT activities is by validating the tests before use, trouble shooting of failed QC, performing maintenance, ensuring operators are trained, inventory control. Main risks of POCT • Unqualified lab users-Nurses – Have minimum lab skills perform POCT testing – They are focused on patient care • Quality Control – A liquid sample of known concentration – Preferably two levels are used to prove stability of the testing. – It detects systemic error not random error Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Role of POCT co-ordiator • • • • • • Training Competency assessment Quality control, internal and external Writing and reviewing the Operating procedures Devices and inventory control Ensuring Results are – reported with an appropriate reference ranges – documented with patient record which are accessible by all care giver Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Anti Coagulation POCT • PT/INR • ACT • TEG Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Why do we need anticoagulant study? Clotting is associated with disease conditions Artificial heart valve replacement Myocardial Ischaemia Atrial fibrillation (AF) Deep Vein Thrombosis (DVT) Pulmonary embolus Hereditary disorders ~ deficiencies in blood proteins or production of antibodies that cause the blood to clot or prevent the blood from clotting Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Why Do We Need PT/INR • PT = Prothrombin Time. It is a measure of how quickly blood clots. • INR = International Normalized Ratio • The ideal target INR range will vary from person to person depending on a variety of factors such as; • Reason for taking anticoagulants • Medical conditions • Other issues. • The traditional way to run a PT-INR test is to have blood drawn and sent to a lab, where the test is conducted Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section PT/INR • Measure of the extrinsic pathway • POCT devices strips containing thromboplastin reagents (variable sources) • Fresh whole blood • Clot detection – The lab uses either optical or mechanical means – POCT • Capillary or pump-induced movement • Oscillation change of a magnetic particle • Electro-current by alteration of fluorescence Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section HMC POCT PT/INR devices Instrument Manufacturer Fresh whole blood Citrated whole blood Citrated plasma Sample size CoagCheck Roche Yes No No 10 – 25ul Hemochron ITC Yes No No 25ul Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Roche CoaguChek XS Pro System Components CoaguChek XS Pro Handheld Base Unit* Handheld Battery Pack* Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section 19 Principle • The CoaguChek test strip contains recombinant thromboplastin reagent. • When the whole blood sample is applied, the reagent is solved and an electrochemical reaction takes place which is transformed into a clotting time value being displayed on the meter screen in INR values. • The international sensitivity index (ISI) for the system has been established as 1 Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Hemochron Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Hemochron Signature Elite Components Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section 22 Hemochron Jr. Test Cuvettes • Test type is read automatically from the cuvette. Cuvette ACT-LR ACT+ Intended Use Specimen Reporting Unit Monitors low to moderate heparin doses up to 2.5 units/mL of blood. Used in procedures such as cardiac catherization, Extracorporeal Membrane Oxygenation (ECMO), dialysis and Pertaneous Transluminal Cornary Angioplasty. Whole blood Celite Equivalent Seconds Monitors moderate to high levels of heparin (16 units/mL ). Unaffected by aprotinin upto 500 KIU/mL of blood, hypothermia, and hemodilution. Whole blood Celite Equivalent Seconds Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section ACT • Coagulation initiated by an activator • Clot detection is change in pump driven blood movement • Strong activator kaolin or celite Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Why use ACT • Monitoring hemostatsis for heparin anticoagulant therapy Bleeding clotting Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section • Rapid TAT • Rapidly adjust anticoagulant dose • Heparin – half life varies by patient – Dose required varies by patient – Potency varies by lot • Direct thrombin inhibitors – very short half life – Require immediate intervention – No antidote available Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section ACT • • • • • • • • Cardiac surgery Percutaneous coronary intervention (PCI) Interventional cardiology ECMO Critical care Interventional radiology Electrophysiology Vascular surgery Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section • • • • ACT APTT Activated clotting time • Activated partial POC Only thromboplastin time Low, moderate or high • Laboratory dose heparin • Low dose heparin only System dependent • System dependent upper limit Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Challenges • Variation in tests results based on the device used • INR corrects for variation, not with ACT • End-user knowledge of the pre-analytical variables- Training – Sample type: cap avoid messaging, arterial or venous avoid trauma – Size: – timing of collection-immediately • Quality assurances Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section Thromboelastograph (TEG) • TEG measures viscoelastic properties (viscosity) of whole blood. • The clot viscoelasticity depends on – Fibrinogen – Platelets – Coagulation – Fibrinolytic proteins TEG TEG- abnormal hemostasis and fibronolysis • Hepatic disease • Cardiac Surgery • ECMO • Assessment of bleeding peri-operatively and following trauma Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section TEG and NICE guidelines • Viscoelastometric POC MAY be useful to help determine if bleeding is because of a problem with the blood’s ability to clot, or because of a surgical bleed. This helps the right treatment to stop the bleeding. • Using these systems MAY mean that patients are less likely to need a blood transfusion during surgery or need more operations to investigate further bleeding. • TEG is recommended to help monitor blood clotting during and after heart surgery by healthcare professionals who have had appropriate training NICE August 2014 Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section THANK YOU Department of Laboratory Medicine & Pathology Point of Care Testing (POCT) Section