 Despite these limitations, heparin remains the most commonly used anticoagulant for hospitalized patients primarily because it is reversible. Newer-generation anticoagulants, such as the LMWHs have improved upon the predictability of UFH dosing and do not require lab-based monitoring as part of their routine use. HIT and HITT are observed less frequently with the LMWHs, relative to UFH, but they have not eliminated this risk. Two of the three commercially available DTIs, lepirudin and argatroban, are specifically approved for use in patients who have developed or have a history of HIT. Bivalirudin is approved for use as an anticoagulant during PCI and therefore provides an attractive alternative to UFH in patients who have HIT. However, there are no direct and clear antidotes to reverse the anticoagulant effects of the LMWHs, nor of the DTIs, which presents a particular risk to their use in patients undergoing surgical or percutaneous coronary revascularization procedures Jones et al., 2002. Bleeding in patients treated with LMWHs or DTIs is managed by administering blood products including clotting factor. 