Overview
What Prophylaxis Prevents
Venous thromboembolism (VTE) includes deep vein thrombosis (DVT) and pulmonary embolism (PE).
Venous thromboembolism (VTE) includes deep-vein thrombosis (DVT) and pulmonary embolism (PE). A DVT usually begins in the deep veins of the leg or pelvis. If part of the clot travels through the right side of the heart to the pulmonary arteries, it becomes a PE, which can impair gas exchange and strain the right ventricle. Clot formation is favoured by three interacting processes: venous stasis, endothelial injury, and hypercoagulability. Bed rest and reduced ambulation slow venous return from the legs. Surgery and central venous catheters can injure the vessel wall. Active cancer, pregnancy and the postpartum state, estrogen exposure, obesity, older age, prior VTE, and inherited or acquired thrombophilia increase the tendency for coagulation. These are not separate memorization lists; they are different routes to the same thrombotic problem. Hospitalization is a particularly important period because acute illness often combines immobility, inflammation, dehydration, surgery, and interruption of usual activity. VTE can first appear after discharge, when the patient and family may no longer associate new symptoms with the hospital stay. Prophylaxis reduces risk; it does not make VTE impossible and...
