Heparin affects which factors (5)
Mainly: Xa and Thrombin
Also: IXa, XIa, and XIIa
HMW heparin binds to?
Antithrombin III
heparin antidote
protamine sulfate
LMW heparin MOA
inhibits factor Xa
protamine sulfate & LMW heparin (2)
does not completely reverse Enoxaprin
No effect of Fondaparinux
LMW indications (3)
subcutaneous injection- not IV
Replacement for warfarin in pregnancy
Lower incidence of heparin-induced thrombocytopenia
direct thrombin inhibitors (3)
lepirudin
argatroban
dabigatran
heparin contraindications (3)
Renal or hepatic dysfunction
Active bleed, hemophilia, after brain/spinal cord/eye surgery
Hx of heparin-induced thrombocytopenia
Lepirudin MOA
highly specific direct inhibitor of thrombin
from leeches
Lepirudin use & cautions
Alternative in HIT
IV only
hypersensitivity rxns
Caution in pts w/ poor renal fxn- use argatroban instead
Argatroban MOA
direct inhibitor of thrombin
Argatroban use and cautions (4)
given as alternative in HIT
cleared by liver
IV
caution w/ poor liver fxn- use lepirudin instead
dabigatran MOA
Oral direct thrombin inhibitor
dabigatran use (3)
prevention of stroke in A Fib pts
Predictable anticoag effects- not monitored by PTT
Cleared by kidneys
dabigatran black box warning?
avoid abrupt discontinuation w/o alternative anticoagulation
oral factor Xa inhibitors (2)
Rivaroxaban (Xarelto)
Apixaban (Eliquis)
rivaroxaban (xarelto) use (3)
DVT
PE
future clots
xarelto & eliquis contraindications (2)
renal failure
liver disease
warfarin MOA
Inhibits vitamin K epoxide reductase
Warfarin interferes with which clotting factors?
II VII IX X Protein C & S
heparin is monitored by?
PTT
warfarin is monitored by?
INR
Warfarin uses (5)
Prevent emboli development DVT Thromboembolism No effect on already-formed thrombi Given chronically
Warfarin antidotes (2)
Vitamin K: takes time
FFP: immediate
Warfarin adverse effects (3)
Hemorrhage
warfarin-induced thrombosis —> cutaneous necrosis & infarction
liver enzyme changes
Warfarin contraindications (4)
pregnancy- category X
Vit K- antibiotics
OCPS
Aspirin
thrombolytic agents (3)
Alteplase (t-PA)
Reteplase
Tenecteplase
Thrombolytic Agents MOA (2 things)
converts plasminogen to plasmin
lyses thrombus from within
what does clot selective mean
higher activity for fibrin-bound plasminogen vs. plasma plasminogen
Alteplase uses (2)
lysis of clots to re-establish tissue perfusion
severe PE, DVT, and arterial thromboses
treatment of Alteplase-related bleeding?
aminocaproic acid and whole blood
Alteplase contraindications
stroke pts
Antifibrolytics (2)
Aminocaproic acid
Tranexamic acid
Antifibrinolytic MOA (2)
inhibits plasminogen activation
inhibits streptokinase activity —> decrease plasmin formation
antifibrinolytic uses (3)
bleeding disorders
adjunct in hemophilia
reveral of fibrinolytic therapy
Aminocaproic acid adverse effects (3)
Intravascular thrombosis
Hypotension
Nasal stuffiness
Aminocapric acid contraindications (2)
DIC
genitourinary bleeding
aspirin MOA
irreversible inhibition of COX enzyme –> decreased TXA2
clopidigrel MOA (2)
irreversibly blocks the ADP receptor on platelets
inhibits platelet aggregation
clopidigrel uses (3)
aspirin allergy
decrease thrombolytic events following MI & stroke
prevent thrombosis in pts undergoing coronary stent placement
clopidigrel adverse rxns
bleeding
drug interactions via CYP2C19
abciximab, eptifibatidine, tirofiban MOA
decrease platelet aggregation by inhibiting GPIIb/IIIa receptors from binding fibrinogen
hemostasis achieved by (3)
Vascular contraction
Platelet adhesion, activation, and aggregation
Fibrin formation & platelet plug
arteries, high flow will form
white thrombus
veins, low flow will form
red thrombus- dangerous
