Pharmacology and Pathophysiology of Coagulation Disorders

What is hyperlipidemia and how does it contribute to cardiovascular disease?

Hyperlipidemia involves cholesterol being deposited on arterial walls, leading to atherosclerosis, which can result in thrombus formation, pulmonary embolism (PE), stroke, or heart attack.

What are the primary treatment goals for hyperlipidemia?

The primary treatment goals are to decrease LDL (low-density lipoprotein) and increase HDL (high-density lipoprotein) through pharmacological and lifestyle changes.

What are some common classes of medications used to treat hyperlipidemia?

Statins, fibric acids, and other agents.

Name three statins and their primary function.

Atorvastatin (Lipitor), Rosuvastatin (Crestor), and Simvastatin (Zocor) are statins that decrease cholesterol production, assist with vasodilation, and stabilize existing plaques.

What are some adverse effects associated with statin use?

Adverse effects include mild gastrointestinal distress, neuromuscular problems, statin-induced myopathy, which can progress to rhabdomyolysis and muscle damage.

What is the role of coagulation in the body?

Coagulation is essential for clotting after injury, preventing excessive blood loss.

What can lead to overactive coagulation and thrombus formation?

Overactive coagulation can result from disease processes and prolonged bed rest.

What is hemostasis and how does it occur?

Hemostasis is the process of blood clotting to prevent blood loss, starting with platelet aggregation (primary) and progressing to a fibrin clot (secondary).

What are the implications of anticoagulant drugs in older adults?

Anticoagulant drugs are commonly implicated in adverse drug reactions (ADRs) leading to emergency department visits, often used for stroke prevention, management of VTE, and myocardial infarction prevention.

What is the mechanism of action of heparin?

Heparin activates antithrombin, leading to an almost immediate effect on clots and requires parenteral administration due to poor GI absorption.

What is the normal reference range for aPTT and its significance?

The normal reference range for aPTT is 30-40 seconds; a therapeutic range is 1.5-2.5 times normal when on anticoagulants.

What is the difference between low molecular weight heparin (LMWH) and unfractionated heparin?

LMWH is administered subcutaneously, has more predictable effects, does not require monitoring, and includes medications like Enoxaparin (Lovenox) and Dalteparin (Fragmin).

What is warfarin and how does it function?

Warfarin (Coumadin) is a vitamin K antagonist that interferes with vitamin K metabolism in the liver, preventing the production of several clotting factors.

What is the normal range for INR and its importance in anticoagulation therapy?

The normal range for INR is 2-3, which is crucial for monitoring patients on warfarin to prevent thromboembolic events.

What are direct thrombin inhibitors and name two examples?

Direct thrombin inhibitors bind to thrombin to inhibit the conversion of fibrinogen to fibrin; examples include Argatroban and Dabigatran (Pradaxa).

What are factor Xa inhibitors and their uses?

Factor Xa inhibitors, such as Fondaparinux (Arixtra), Apixaban (Eliquis), and Rivaroxaban (Xarelto), are used for the treatment and prevention of VTE and stroke prevention in patients with atrial fibrillation.

What are the adverse effects of anticoagulants?

Adverse effects can include increased bleeding risk, which can complicate rehabilitation efforts.

What is the role of antiplatelet drugs in cardiovascular therapy?

Antiplatelet drugs, such as aspirin and ADP receptor blockers, inhibit platelet aggregation to prevent thrombus formation.

How does aspirin function as an antiplatelet drug?

Aspirin inhibits prostaglandins and thromboxanes, which are necessary for platelet aggregation, and can be effective in acute infarction.

What are ADP receptor blockers and their indications?

ADP receptor blockers, such as Clopidogrel (Plavix) and Ticagrelor (Brilinta), are used for patients at risk for myocardial infarction or ischemic stroke.

What is thrombocytosis and its potential symptoms?

Thrombocytosis is an increase in platelet count, with symptoms including headache, dizziness, weakness, and chest pain.

What is thrombocytopenia and its implications?

Thrombocytopenia is a decrease in platelet count, leading to symptoms like petechiae, ecchymosis, and increased risk of spontaneous bleeding.

What is Von Willebrand Disease (VWD) and its primary treatment?

VWD is the most common inherited bleeding disorder caused by a lack or dysfunction of von Willebrand factor, treated with factor VIII concentrate.

What are the characteristics of hemophilia?

Hemophilia is a sex-linked autosomal recessive disorder primarily affecting males, characterized by spontaneous bleeding, particularly in joints and muscles.

What is Disseminated Intravascular Coagulation (DIC) and its clinical manifestations?

DIC is characterized by overactivity of the coagulation cascade leading to small blood clots and bleeding; clinical manifestations include tissue ischemia, shock, and bleeding without injury.

What precautions should be taken during physical therapy for patients with DIC?

In patients with DIC, avoid dislodging clots or causing new bleeding, monitor labs and vitals, and handle patients carefully due to fragile skin.