use of medicines - antithrombosis

Question 1

appearance of venous vs arterial thrombus

Answer 1

venous - red

arterial - white

Question 2

content of venous vs arterial thrombus

Answer 2

venous - fibrin rich (RBC trapped hence red)

arterial - platelet rich (hence white)

Question 3

therapy of venous vs arterial thrombus

Answer 3

venous - heparin and warfarin (as fibrin rich)

arterial - antiplatelet agents (as platelet rich)

Question 4

evidence for anti platelet drugs in secondary precention

Answer 4

in all high risk people the risk is reduced by 25% with aspirin - BMJ metaanalysis

75mg as effective as higher doses for long term use though a higher loading dose is used in acute treatment.

Question 5

use of dypyridamole

Answer 5

not widely used

Question 6

use of clopidogrel

Answer 6

taking over from aspirin. marginally better efficacy that aspirin (CAPRIE trial). now off patent.

Question 7

is clopidogrel an active drug

Answer 7

no, a prodrug. has to be metabolised by a CYP enzyme. interaction with omeprazole.

Question 8

therapeutic window for warfarin

Answer 8

between an INR of 1.7 and 4.0

diffferent doses needed for different individuals