RT Book, Section A1 Nelson, Jessie G. A1 Hemphill, Robin R. A2 Tintinalli, Judith E. A2 Stapczynski, J. Stephan A2 Ma, O. John A2 Yealy, Donald M. A2 Meckler, Garth D. A2 Cline, David M. SR Print(0) ID 1121500709 T1 Clotting Disorders T2 Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8e YR 2016 FD 2016 PB McGraw-Hill Education PP New York, NY SN 9780071794763 LK accessemergencymedicine.mhmedical.com/content.aspx?aid=1121500709 RD 2024/10/05 AB Most patients who develop an arterial or venous thrombosis do so because of local factors (e.g., a focal atherosclerotic lesion producing a thrombus in an coronary artery) or major systemic events (e.g., trauma, surgery, or prolonged immobilization). However, several inherited genetic mutations predispose patients to venous thromboembolism with some studies finding up to 50% of patients with venous thromboembolism having a thrombophilia (Table 234-1).1 Importantly, risk for clotting from genetic, acquired, and environmental factors is additive or even multiplicative; a patient with mild deficiency may develop a deep venous thrombosis when started on estrogen.2