It depends on the blood thinner. Coumadin, Aspirin, Plavix, etc, can work via different methods. So, yes, ask the doctor! Looking at how it works, by 'absorbing the fluid, leaving the clotting agents,' I would think that it wound't help much. Most blood thinners act by disrupting different steps in the coagulation cascade. think of building a fence: the platelets are the wood, the coag. factors are the nails. You reduce the nails with blood thinners, making it harder to clot.

http://www.defensetech.org/archives/000458.html
http://www.z-medica.com/quikclot/index.asp