Patient Assessment and Management Flashcards
What are the potential barriers to successful use of anticoag medication and management.
financial hardship transportation literacy health literacy communication language barrier
what anticoagulants can be used in pregnancy?
UFH
(LMWH over UFH except during the final wks of pregnancy for fast reversal for delivery)
Less info on Fonda/argatroban/danaparoid
Why cant you use warfarin in pregnancy
crosses the placenta and can cause miscarriage’s, embryopathy (early exposure), Fetal bleeding, Intracranial hemorrhage (late exposure)
why cant you use DOAC in pregnancy (what can it cause)
Miscarriages, embryopathy (facial dimorphism, limb deformity, cardiac defect)
when do you switch from LWMH to UFH when pregnant
at 36-37 wk gestation, to minimize the risk, or stop LMWH 24 hours prior to delivery
what anticoagulants can be used while breastfeeding
LMWH, UFH, Fonda, Warfarin
DO NOT USE DOAC
Pradaxa is the only DOAC that can be used in Children in what ages and for what indication has it been FDA approved
children 3 months to less than 12 years old with venous thromboembolism
what is the preferred anticoagulation therapy in children
LMWH Fragmin (Dalteparin ONLY one FDA approved)
although unfractionated heparin and warfarin remain frequently used. Other anticoagulants, including fondaparinux, direct thrombin inhibitors, and the newer target-specific oral anticoagulants are also discussed.
what are the advantages of using DOAC in children
oral dosage formulations, including oral suspension; minimal laboratory monitoring; predictable pharmacokinetics; and no food interactions
Preferred anticoagulant in elderly pts greater than 75
apixaban
what is the preferred Anticoagulant in pts with hepatic failure
warfarin
Then can consider dabigatran
what is the preferred anticoagulant in pts with renal failure
Unfractionated heparin (UFH)
can consider apixaban
what is the ISI when calculating INR?
ISI indicates how particular a batch of tissue factor compares to an international reference tissue factor
how does POC vs Venous testing affect the correlation between INR values
It loses correlation once INR is over 4 (or per manufacturer)
Define Prothrombin time (PT)
measures the time it takes plasma to clot when exposed to tissue factor (which assesses the extrinsic and common pathways of coagulation. Its performed by recalcifying citrated patient plasma in the presence of tissue factor and phospholipid and determining the time it takes to form a fibrin clot. The formation of a fibrin clot is detected by visual, optical, or electromechanical methods. The result is measured in seconds and reported along with a control value and/or an INR.)
what can an INR result be useful for?
INR is standardized and can be evaluated regardless of time/location
evaluation of bleeding in patient/ warfarin monitoring
assessment of liver synthetic function
Disseminated intravascular coagulation (DIC) is a serious disorder in which the proteins that control blood clotting become overactive.
what can prolong the INR
warfarin, DOACs, heparins, Vit K deficiency, liver disease, DIC, APLS HCT greater than 55%
Define Activated partial thromboplastin time (aPTT)
(not standardized - location specific)
measures the time it takes plasma to clot when exposed to substances that activate the contact factors, which assesses the intrinsic and common pathways of coagulation. It is performed by recalcifying citrated plasma in the presence of a thromboplastic material that does not have tissue factor activity (hence the term partial thromboplastin) and a negatively charged substance (eg, celite, kaolin [aluminum silicate], silica), which results in contact factor activation, thereby initiating coagulation via the intrinsic clotting pathway.
For heparin monitoring aPTT range should be what?
- 2-0.4 units/mL by protamine or
0. 3-0.7 anti-factor Xa units/mL
what is aPTT used for
Evaluating bleedign, DIC, UFH monitoring or DTI monitoring
what can prolong aPTT
DIC, vWB (von wildebrand factor), hemophilia A (def FVIII), and B (FIX), oritavacin (binds phospholipids), Lupus anticoag type inhibitors
Definite TT (Thrombin time) (not for initial screening but can be used to eval pts with prolonged PT and aPTT, inherited fibrinogen disorder)
measures the final step of coagulation, the conversion of fibrinogen to fibrin. It is performed by incubating citrated plasma in the presence of dilute thrombin (bovine [cow] or human) and measuring the time to clot formation
What can prolong TT (thrombin time)?
Heparin, LMWH, Bilval, argatroban, acquired fibronioge disorders, DIC, liver disease, hypoalbuminemia, paraproteinemias, bovine thrombin exposure
How is Anti-Xa assay performed?
adding patient plasma to reagent factor Xa and measuring the activity of factor Xa using an artificial factor Xa substrate that releases a colored compound when cleaved (ie, chromogenic assay) but NOT chromogenic factor Xa level!
Must be calibrated for specific agents