Hematology

Question 1

Heparin MOA

Answer 1

-binds to AT3 & enhances rate of thrombin-AT formation by 1,000-10,000x

Question 2

Heparin S/E

Answer 2

• hemorrhage
• -HIT
• -allergic rxn
• -HoTN
• -altered protein binding
• -↓AT3 conc

Question 3

Heparin Consideration

Answer 3

stop 6h (heparin) & 12h (LMWH) before surgery

Question 4

Contraindications for heparin

Answer 4

-HIT hx
-neuro & eye surgery

Question 5

AntiPLT drugs are

Answer 5

COXi (ASA), ADPi (clopidogrel), IIb/IIIa antagonists (abciximab)

Question 6

MOA of antiPLTs

Answer 6

-blocks receptors on plts = impairs plt function
-ASA impairs TxA2 synthesis

Question 7

AntiPLTs S/E

Answer 7

-thrombocytopenia (irreversibly bind to plt = last life the plt)

Question 8

Warfarin MOA

Answer 8

-inhibits vit K epoxide (II, VII, IX, X)

Question 9

Warfarin S/E

Answer 9

-bleeding
-compression neuropathy
-skin necrosis

Question 10

Warfarin stop before what surgery

Answer 10

-stop 1-7 days before surgery

Question 11

Warfarin reversal

Answer 11

-1-2mg of Vit K
-1-2u FFP
-prothrombin complex conc
-recombinant VIIa

Question 12

Thrombin Inhibitors SE

Answer 12

Suppress plt fx

Question 13

Thrombin Inhibitors Complications

Answer 13

-recent surgery (10d)
-GI bleed (3mo)
-HTN (DBP > 110)
-pregnancy
-aortic dissection I
-hemorrhagic disorder
-CVA hx
-acute pericarditis
-active intracranial process

Question 14

Thrombin Inhibitors

Answer 14

-argatroban
-____rudin

Question 15

Thrombolytics MOA

Answer 15

-plasminogen activator (convert plasminogen to plasmin)

Question 16

antifibrinolytics: Endogenous vs exogenous

Answer 16

Endogenous: a-antiplasmin, plasminogen activating inhibitors
Exogenous: lysine analogs (amicar, TXA), polypeptide protease inhibitors (aprotinin)
- Used to ↓blood loss, ↓transfusion requirements, and reoperation

Question 17

Antifibrinolytics MOA

Answer 17

-competitively inhibit activation of plasminogen to plasmin
○ Amicar can block the binding to fibrin
○ TXA inhibits plasmin at high doses, 16x more potent than amicar

Question 18

Amicar and TXA dosing

Answer 18

amicar
-10g + 10-15 mg/kg/hr
-want 130 mg/l plasma lvl
TXA
-10 mg/kg + 1 mg/kg/hr for 12h OR 20 mg/kg preop

Question 19

Contraindications for antifibrinolytics

Answer 19

Contraindications: thromboembolic disorder, DIC, renal failure, vascular stent w/in 6mos to 1y,
acute subarachnoid hemorrhage
Relative: uncontrolled sz disorder, renal/liver/ CVdysfunc, risk of venous/arterial thrombosis, pre-existing coagulopathy or oral anticoagulant tx