Wolff PAD Flashcards
1
Q
MOA of Cilostazol?
A
- type 3 PDEI, this prolongs life of cAMP in platelets and cells
2
Q
Effects and clinical application of Cilostazol?
A
- Used for intermittent claudication
- inhibits platelet aggregation
- acts as vasodilator
3
Q
AE of Cilostazol?
A
- HA
- Diarrhea
- Palpitations
- dizzy
- peripheral edema
4
Q
BBW for Cilostazol?
A
Contraindicated in those with HF, its use decreases survival in class III and IV HF
5
Q
Unfractionated Heparin MOA?
A
- mix of long polysaccharide chains
- Pentasaccharide sequence found along length that binds and activates antithrombin III to inhibit factor Xa via formation of thrombin
6
Q
Effects and clinical use of heparin?
A
- Blocks generation of thrombin and inactivates thrombin
- prevents red clot formation
- Used for PE, stroke, DVT, DIC, MI
- Can be used in pregnancy
7
Q
Antidote to Heparin and pharmacokinetics?
A
- 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
8
Q
Contraindications/warnings for Heparin?
A
- thrombocytopenia and uncontrollable bleeding
- surgeries involving brain eye or spinal cord
- liver/kidney disease
- HITT
9
Q
What is enoxaparin and it’s MOA?
A
- low molecular weight heparin
- shorter length heparin that inhibits factor Xa preventing red clots
10
Q
Clinical application of Enoxaparin?
A
- prevent DVT after surgery
- tx DVT w/wo PE
- Prevent ischemic complications
- safe in pregnancy
11
Q
Pharmacokinetics of Enoxaparin?
A
- easier to use with predictable dosing
- first choice for tx/prevent DVT
- long half life
- costly
12
Q
Toxicities of Enoxaparin?
A
- bleeding (protamine is antidote)
- HITT
- severe neurologic injury with spinal puncture or epidural
13
Q
What is Fondaparinux and MOA/effects?
A
- 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
14
Q
Use of fondaparinux?
A
- prevent/tx DVT
- tx PE use with warfarin
15
Q
Toxicities of Fondaparinux?
A
- bleeding NOT reversible with protamine
- does not cause heparin induced thrombocytopenia
16
Q
Compare Heparin vs LMW Heparin MOA?
A
- Heparin inhibits factor Xa and thrombin and requires PTT monitoring
- LWM Heparin only blocks Xa and doesn’t require monitoring
17
Q
What is Bivalirudin?
A
- Blocks thrombin directly
- reversibly inhibits thrombin at the catalytic site and substrate binding site
18
Q
Uses of Bivalirudin and pharmacokinetics?
A
- in combo with aspirin to patients undergoing coronary angioplasty
- Given IV
- Expensive
19
Q
Bivalirudin toxicities?
A
- As effective as Heparin and doesn’t require antithrombin and causes less bleeding
- NO antidote
- anaphylaxis with repeated use
20
Q
Argatroban MOA, use and pharmacokinetics, and toxicities?
A
- 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
21
Q
Warfarin MOA?
A
- Vitamin K antagonist
- Decreases production of biologically active forms of calcium dependent clotting factors II, VII, IX and X, protein C and S
22
Q
Clinical uses of Warfarin?
A
- Most widely used for long term prophylaxis of thrombosis for prevention of:
- DVT
- Thromboembolism with mechanical heart valves
- A. fib
- not useful in emergency
23
Q
Contraindications for Warfarin?
A
- Severe thrombocytopenia or uncontrolled bleeding
- any surgery with eye brain or spinal cord
- hemophilia ulcer or alcoholic patients
24
Q
Pharmacokinetics of Warfarin?
A
- 100% bioavailability
- eliminate by liver in bile
- Slow onset and offset
- monitored with prothrombin time ratio
- want INR of 2-3
25
Warfarin toxicites?
* Bleeding
* if occurs discontinue and administer vitamin K slowly
* fresh whole blood/ plasma if urgent
* **Crosses placenta and causes death**
26
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
27
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
28
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
29
What is apixaban comparable to, but better than?
Rivaroxaban, it has same benefits but with less bleeding
30
Dabigatran MOA?
* Direct oral anticoagulant that inhibits thrombin
* directly blocks thrombin
31
Dabigatran 5 advantages over Warfarin?
* rapid onset
* no need to monitor
* few drug/food interactions
* low risk of bleeding
* same dose for all patients
32
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
33
Toxicities of Dabigatran and antidote?
* bleeding
* antidote is idarucizumab
34
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
