Leona is 52 years old and smokes. She is also overweight and has atherosclerosis. When she was given a 2-week vacation from work, she packed up her bags and flew from Minnesota to Sydney, Australia, for the trip she always wanted to take. Unfortunately, just 3 days after she arrived, she was hospitalized when her left calf became inflamed, causing her considerable pain. The physician attending to her told her she developed a deep vein thrombosis. (Learning Objectives: 6, 9, and 11)
- Explain, using your knowledge of hypercoagulability, why the trip to Australia contributed to Leona’s DVT? Why was Leona already at risk for thrombus development?
- How does Leona’s atherosclerosis affect platelet function? Conversely, what is the effect of increased platelet activity on the development of atherosclerosis?
- How do atherosclerosis and immobility promote changes in blood coagulation?
- When Leona was in hospital, she received heparin therapy. Explain why this course of action was taken to treat her DVT. Why was she not given heparin tablets to take back to the hotel with her?
Needs two sources in APA format.
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Introduction:
The case of Leona, a 52-year-old smoker who developed deep vein thrombosis (DVT) after traveling to Australia, poses several questions related to hypercoagulability, atherosclerosis, platelet function, immobility, and therapeutic interventions. This article aims to provide comprehensive answers to each question based on relevant literature and medical knowledge.
1. Leona’s DVT was likely caused by several factors, including immobility during her long airplane journey, hypercoagulability, and atherosclerosis. Hypercoagulability refers to an increased tendency of blood clotting and is caused by various factors, such as genetic predisposition, hormonal imbalances, and underlying medical conditions. In Leona’s case, being overweight, smoking, and having atherosclerosis were contributing factors. Atherosclerosis involves the buildup of plaque in arterial walls, which can activate platelets and increase the risk of thrombosis. Additionally, immobility during long flights can cause blood to pool in the legs, leading to stasis and increasing the risk of DVT.
2. Atherosclerosis can affect platelet function by stimulating their activation and aggregation. Plaque components, such as collagen and von Willebrand factor, can attract platelets and cause their activation, leading to the formation of platelet-rich thrombi. Conversely, increased platelet activity can worsen atherosclerosis by promoting plaque formation and progression. Platelets can trigger the release of cytokines, growth factors, and chemokines that attract immune cells and promote inflammation, which further exacerbates plaque buildup.
3. Atherosclerosis and immobility can promote changes in blood coagulation by altering the balance between procoagulant and anticoagulant factors. Plaque components can activate the coagulation cascade and enhance thrombin generation, leading to an excess of fibrin production and clot formation. Immobility can also reduce fibrinolysis, which is the process of breaking down clots, and impair venous blood flow, which can exacerbate stasis and thrombosis.
4. Leona received heparin therapy in the hospital to prevent the propagation of her existing clot and reduce the risk of embolism. Heparin is an anticoagulant medication that works by inhibiting thrombin and preventing the conversion of fibrinogen to fibrin. It can also enhance the activity of antithrombin III, a natural anticoagulant protein in the blood. Heparin is typically administered intravenously to achieve a therapeutic effect quickly and can be adjusted based on frequent coagulation tests to ensure safety and efficacy. Heparin tablets were not given to Leona because oral anticoagulants, such as warfarin, are typically used for long-term management of DVT after an initial course of heparin. Additionally, oral anticoagulants require monitoring of the international normalized ratio (INR), a measure of blood clotting time, and can interact with various foods and drugs, making their management challenging for patients.
