Pulmonary Embolism：肺栓塞.pptVIP

Pulmonary Embolism PE Epidemiology Pathophysiology Prevention/Risk factors Screening Diagnosis Treatment PE Epidemiology Five million cases of venous thrombosis each year 10% of these will have a PE 10% will die Correct diagnosis is made in only 10-30% of cases Up to 60% of autopsies will show some evidence of past PE PE Epidemiology 90-95% of pulmonary emboli originate in the deep venous system of the lower extremities Other rare locations include Uterine and prostatic veins Upper extremities Renal veins Right side of the heart Risk Factors CHF Malignancy Obesity Estrogen/OCP Pregnancy (esp post partum) Lower ext injury Coagulopathy Venous Stasis Prior DVT Age 70 Prolonged Bed Rest Surgery requiring 30 minutes general anesthesia Orthopedic Surgery Virchow抯 Triad Rudolf Virchow postulated more than a century ago that a triad of factors predisposed to venous thrombosis Local trauma to the vessel wall Hypercoagulability Stasis of blood flow It is now felt that pts who suffer a PE have an underlying predisposition that remains silent until a acquired stressor occurs Factor V Leiden mutation Protein C deficiency Protein S deficiency Antithrombin deficiency Prothrombin gene mutation A20210 Anticardiolipin antibodies Lupus anticoagulant Hyperhomocystinemia Factor V Leiden Most frequent inherited predisposition to hypercoagulability Resistance to activated Protein C Single point mutation (Factor V Leiden) Single nucleotide substitution of glutamine for arginine Frequency is about 3% in healthy American male physicians participating in the Physicians?Health Study PE When venous emboli become dislodged from their site of origin, they embolize to the pulmonary arterial circulation or, paradoxically to the arterial circulation through a patent foramen ovale About 50% of pts with pelvic or proximal leg deep venous thrombosis have PE Isolated calf or upper extremity venous thrombosis pose a lower risk for PE Pathophysiology Increased pulmonary v