The nurse manages complex anticoagulation therapy including heparin infusion titration protocols, warfarin dose adjustments based on INR trending, LMWH bridging therapy, DOAC management, HIT surveillance, and periprocedural anticoagulation management. Advanced pharmacology: UFH has variable bioavailability due to binding to plasma proteins, endothelial cells, and macrophages, creating a nonlinear dose-response that necessitates aPTT monitoring. The aPTT measures the intrinsic pathway (factors XII, XI, IX, VIII) plus the common pathway (X, V, II, fibrinogen). Heparin resistance occurs when high doses (more than 35,000 units/day) fail to achieve therapeutic aPTT, often due to AT-III deficiency, elevated factor VIII (acute phase reactant), or high heparin-binding proteins. Anti-Xa levels are more reliable than aPTT in these cases. Warfarin pharmacogenomics: CYP2C9 and VKORC1 genetic polymorphisms significantly affect warfarin metabolism and sensitivity. CYP2C9 poor metabolizers require lower doses; VKORC1 variants affect vitamin K recycling efficiency. DOACs have transformed anticoagulation management: predictable pharmacokinetics eliminate routine monitoring, fixed dosing simplifies management, shorter half-lives (5-17 hours) reduce bleeding duration, and specific reversal agents are available. However, DOACs are renally cleared to varying degrees (dabigatran 80%, rivaroxaban 33%, apixaban 27%), requiring...