TY - CHAP M1 - Book, Section TI - Anticoagulation A1 - Tapson, Victor F. A1 - Shirvanian, Shant A2 - Oropello, John M. A2 - Pastores, Stephen M. A2 - Kvetan, Vladimir Y1 - 1 N1 - T2 - Critical Care AB - KEY POINTSAnticoagulation is the key in the management of venous thromboembolism (VTE), atrial fibrillation (AF), mechanical heart valves, and idiopathic pulmonary arterial hypertension (IPAH).Critically ill patients are at increased risk for complications with anticoagulant therapy due to their underlying disease states, presence of thrombocytopenia, coagulopathy, renal and hepatic failure, need for invasive procedures, and the potential for major surgery.Intravenous unfractionated heparin (UFH) remains the most commonly utilized parenteral therapy when therapeutic doses are needed in the critically ill. Monitoring with the activated partial thromboplastin time (aPTT) or heparin level (anti–factor Xa assay) is required.Heparin resistance may occur due to nonspecific binding of the drug to various plasma proteins, altered intravascular volume, and/or increased heparin clearance. In cases of heparin resistance, anti-Xa level should be utilized for monitoring.Low-molecular-weight heparins (LMWHs) have several advantages over UFH including greater bioavailability and more predictable effects, lesser incidence of thrombocytopenia, and in general do not require monitoring except in patients who are morbidly obese, pregnant, or with severe renal insufficiency.Argatroban is a synthetic direct thrombin inhibitor that is approved for prevention and treatment of VTE in patients with heparin-induced thrombocytopenia (HIT).Novel oral anticoagulants inhibit either thrombin (factor IIa) or factor Xa. They include rivaroxaban, apixaban, edoxaban and dabigatran etexilate. These agents do not require routine monitoring.The risk/benefit of anticoagulant discontinuation for emergent procedures including surgery depends on the reason the patient is anticoagulated, the bleeding risk imparted by the procedure, and concomitant comorbidities.Warfarin and other vitamin K antagonists (VKAs) may be reversed with vitamin K and/or fresh frozen plasma (FFP).Four-factor prothrombin complex concentrate (PCC) is approved for use in the United States for warfarin reversal in the setting of severe bleeding. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accessanesthesiology.mhmedical.com/content.aspx?aid=1136415003 ER -