NMS. Surgery

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Part I ♦ Foundations B. Hemophilia B: Congenital deficiency of factor IX; treatment is factor replacement. FFP can be used in emergent situations. VIII. von Willebrand disease: The most common congenital coagulopathy (1% of adults) is deficiency of von Willebrand factor. Treatment is intranasal DDAVP in mild cases, IV DDAVP prior to surgical procedures, and cryoprecipitate or FFP in emergencies. IX. Others: Autoimmune diseases, cancer, snake venom. Specific Hypercoagulable States I. Surgical patients: Surgery, trauma, and sepsis cause pro-inflammatory states that lead to a hypercoagulable state; therefore, surgical patients are at risk for deep venous thrombosis (DVT) . A. Major risk factors: Include abdominal or pelvic surgery, orthopedic surgery, especially lower extremity, trauma, especially spine, pelvis, and lower extremity fractures, prolonged immobilization, cancer, smoking, obesity, age, central lines. B. Prophylaxis. Heparin 5,000 units subcutaneously every 8 hours or low- molecular-weight heparin subcutaneously daily or twice daily. In patients who have contraindications to prophylaxis (e.g., intracranial bleed), inferior vena cava filters should be considered. II. Congenital risk factors: Suspect if patients have multiple DVT or DVT without another known risk factor; treatment is usually anticoagulation.

A. Protein S Deficiency B. Protein C Deficiency

C. Factor V Leiden Mutation D. Antithrombin III Mutations E. Other Clotting Cascade Mutations

Quick Cuts • Prothrombin time reflects intrinsic pathway. PTT reflects extrinsic pathway. • Severe thrombocytopenia (<10,000/mL) leads to spontaneous bleeding.

PACKED RED BLOOD CELL TRANSFUSION THERAPY Transfusion Risks I. Febrile reactions/allergic: Most common immune reaction A. Usually related to cytokines, donor leukocytes, contaminants or a mild antibody response; usually self-limited. B. The longer blood is stored, the worse it performs. Over time, cells lyse, and 2,3-diphosphoglycerate (2,3-DPG) levels fall, causing oxygen to bind more avidly. C. Can be prevented by leukodepletion and pretransfusion antipyretics.