Low molecular weight heparin affects which factor:

Ref: KD Tripathi, 6th Ed. pg. 597-598* Low molecular heparin inhibits factor Xa mainly, having some action at factor IIa as well. It doesn't require monitoring because of consistent bioavailability.* Heparin is a powerful and instantaneously acting anticoagulant, effective both in vivo and in vitro.* It acts indirectly by activating plasma antithrombin III* The heparin -AT III complex then binds to clotting factors of the intrinsic and common pathways (Xa, IIa, IXa, XIa, XIIa and XIIIa) and inactivates them.* Warfarin on the other hand is effective only in vivo (body). It acts by inhibiting vitamin K.Note* Fondaparinaux is synthetic LMWH acts exclusively at factor Xa.