Wolff PAD Flashcards
MOA of Cilostazol?
- type 3 PDEI, this prolongs life of cAMP in platelets and cells
Effects and clinical application of Cilostazol?
- Used for intermittent claudication
- inhibits platelet aggregation
- acts as vasodilator
AE of Cilostazol?
- HA
- Diarrhea
- Palpitations
- dizzy
- peripheral edema
BBW for Cilostazol?
Contraindicated in those with HF, its use decreases survival in class III and IV HF
Unfractionated Heparin MOA?
- mix of long polysaccharide chains
- Pentasaccharide sequence found along length that binds and activates antithrombin III to inhibit factor Xa via formation of thrombin
Effects and clinical use of heparin?
- Blocks generation of thrombin and inactivates thrombin
- prevents red clot formation
- Used for PE, stroke, DVT, DIC, MI
- Can be used in pregnancy
Antidote to Heparin and pharmacokinetics?
- protamine, with many positive charges that bind ionically with negative heparin
- Given IV or SC as can’t cross cell mem
- intensive monitoring of plasma levels with PTT
Contraindications/warnings for Heparin?
- thrombocytopenia and uncontrollable bleeding
- surgeries involving brain eye or spinal cord
- liver/kidney disease
- HITT
What is enoxaparin and it’s MOA?
- low molecular weight heparin
- shorter length heparin that inhibits factor Xa preventing red clots
Clinical application of Enoxaparin?
- prevent DVT after surgery
- tx DVT w/wo PE
- Prevent ischemic complications
- safe in pregnancy
Pharmacokinetics of Enoxaparin?
- easier to use with predictable dosing
- first choice for tx/prevent DVT
- long half life
- costly
Toxicities of Enoxaparin?
- bleeding (protamine is antidote)
- HITT
- severe neurologic injury with spinal puncture or epidural
What is Fondaparinux and MOA/effects?
- Synthetic pentasaccharide identical to antithrombin binding structure of heparin
- Selectively inhibits factor Xa preventing conversion of prothrombin to thrombin
- slightly more effective than enoxaparin but increased risk of bleeding
Use of fondaparinux?
- prevent/tx DVT
- tx PE use with warfarin
Toxicities of Fondaparinux?
- bleeding NOT reversible with protamine
- does not cause heparin induced thrombocytopenia
Compare Heparin vs LMW Heparin MOA?
- Heparin inhibits factor Xa and thrombin and requires PTT monitoring
- LWM Heparin only blocks Xa and doesn’t require monitoring
What is Bivalirudin?
- Blocks thrombin directly
- reversibly inhibits thrombin at the catalytic site and substrate binding site
Uses of Bivalirudin and pharmacokinetics?
- in combo with aspirin to patients undergoing coronary angioplasty
- Given IV
- Expensive
Bivalirudin toxicities?
- As effective as Heparin and doesn’t require antithrombin and causes less bleeding
- NO antidote
- anaphylaxis with repeated use
Argatroban MOA, use and pharmacokinetics, and toxicities?
- Directly binds catalytic site of thrombin
- Prophylaxis and tx of thrombosis in patients with HIT
- Efficacy monitored by PTT
- Given IV short half life
- Risk of hemorrhage and hematuria
Warfarin MOA?
- Vitamin K antagonist
- Decreases production of biologically active forms of calcium dependent clotting factors II, VII, IX and X, protein C and S
Clinical uses of Warfarin?
- Most widely used for long term prophylaxis of thrombosis for prevention of:
- DVT
- Thromboembolism with mechanical heart valves
- A. fib
- not useful in emergency
Contraindications for Warfarin?
- Severe thrombocytopenia or uncontrolled bleeding
- any surgery with eye brain or spinal cord
- hemophilia ulcer or alcoholic patients
Pharmacokinetics of Warfarin?
- 100% bioavailability
- eliminate by liver in bile
- Slow onset and offset
- monitored with prothrombin time ratio
- want INR of 2-3
Warfarin toxicites?
- Bleeding
- if occurs discontinue and administer vitamin K slowly
- fresh whole blood/ plasma if urgent
- Crosses placenta and causes death
Rivaroxaban MOA and effects and advantage over warfarin?
- Direct inhibiitor of activated factor X
- directly inhibits production of thrombin
- Advantages:
- rapid onset
- fixed dose
- lower bleeding risk
- fewer drug interaction
- no need for iNR
Clinical uses of Rivaroxaban?
- prevent DVT and PE after surgery
- prevention of stoke in patients with nonvalvular atrial fib
- andexanet alfa is antidote
- used off label for HIT
Toxicities of Rivaroxaban? (7)
- bleeding
- epidural hematoma
- major intracranial retinal bleeds
- adrenal bleeds
- avoid with hepatic/renal impairment
- unsafe for pregnancy
- don’t combine with other anticoagulatns
- interacts with CYP3A4
What is apixaban comparable to, but better than?
Rivaroxaban, it has same benefits but with less bleeding
Dabigatran MOA?
- Direct oral anticoagulant that inhibits thrombin
- directly blocks thrombin
Dabigatran 5 advantages over Warfarin?
- rapid onset
- no need to monitor
- few drug/food interactions
- low risk of bleeding
- same dose for all patients
Dabigatran uses, contraindications, and pharmacokinetics?
- prevent stroke and systemic embolism with nonvalvular a fib
- contraindicated for those with mechanical heart valves
- pills are unstable and kept in specific environment
Toxicities of Dabigatran and antidote?
- bleeding
- antidote is idarucizumab
How do you monitor heparins, warfarins, DOAC factor Xa inhibtors, and DOAC direct thrombin inhibitors?
- heparin
- PTT
- Warfarin
- INR
- Factor Xa inhibitor
- anti-Xa
- Direct thrombin inhibitor
- diluted TT
