Pharm III - Hefnawy

Question 1

do you want plasmin floating around in blood freely?

Answer 1

NO

-degrades/damages everything causing more bleeding

Question 2

streptokinase***

Answer 2

• can bind any plasminogen activating it (free floating or in the fibrin clot)***
• less effective - more plasminogen is bound to inhibitors in blood
• higher risk of hemorrhage/side effects
• made by streptococci –> repeated injections can lead to antibody formation –> anaphylaxis**

convert plasminogen to plasmin

Question 3

alteplase*** - recombinant tissue plasminogen activator

Answer 3

• only binds/activates plasminogen associated with fibrin clot** (rarely binds to circulating plasminogen)
• more effective - inhibitors can’t reach plasminogen in clot
• lower risk of hemorrhage

convert plasminogen to plasmin

Question 4

when do you give fibrinolytics?

Answer 4

• in PE*
• not in uncomplicated DVT*
• MI - act fast
• acute thromboembolic disorders
• can inject venously or directly into fibrin clot (less side effects bc it is only interacting with the plasminogen in fibrin clot)***
• activation of circulating plasminogen leads to more bleeding

Question 5

D-dimers

Answer 5

• formed from degradation of cross-linked fibrin**

- not formed with non cross-linked fibrin

Question 6

contraindications of fibrinolytics

Answer 6

• aortic dissection –> degrading fibrin clot would burst aorta
• bacterial endocarditis, pericarditis

Question 7

tenecteplase

Answer 7

• genetically engineered mutant of t-PA
• longer half-life
• higher affinity to fibrin bound plasminogen than altepase. –> lower risk for hemorrhage**
• resistant to plasminogen activator inhibitor* (PAI1)
• only one injected in single bolus**
• used during ST segment elevation MI (STEMI)** during transport of patient

Question 8

fibrinolytic inhibitors

Answer 8

1. Aminocaproic acid (EACA)
2. Tranexamic Acid (7x more potent)

• lysine analogs
• used to stop severe bleeding
• interfere with lysine binding site on plasminogen –> cannot bind to fibrin when activated to plasmin**

Question 9

EACA

Answer 9

• antidote for fibrinolytic agents
• give for hyperplasminemia
• be careful in hematuria –> can form clots in kidney

Question 10

tranexamic acid

Answer 10

• antidote for fibrinolytic agents
• 7x more potent than EACA
• used to stop bleeding –> bypass surgery, hemorrhage due to IUD, hemophilia patients

Question 11

what can you do to prevent warfarin toxicity?

Answer 11

-give coag factors 2,7,9,10 or frozen plasma*

Question 12

eptacog alpha

Answer 12

• recombinant activator of coagulation factor 7** –> extrinsic cascade
• also activates factors 9,10
• administered IV
• given for hemophilia or hemorrhage

Question 13

factor 9 complex

Answer 13

• plasma fraction contains factors 2,7,9,10*
• administered IV

indications: Hemophilia B, warfarin toxicity, antibodies against factor 8
contraindications: thrombosis, DIC

Question 14

protamine

Answer 14

• derived from sperm/testes of salmon
• given as protamine sulfate –> antidote for UF heparin (not as good for LMW heparin)
• can have allergic rxns**

Question 15

desmopressin

Answer 15

• analog of vasopressin
• hypercoagulation bc it increases release of vWF from the platelets**
• leads to increase in factor 8**
• drug for hemophilia A and von willebrand disease**

Question 16

oral contraceptives

Answer 16

• increase the risk for DVT and thrombosis**
• increases factors 2,7,8,10 and fibrinogen
• decreases antithrombin and protein S