الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The platelet is integral to the initiation of thrombosis. Drugs that affect platelet function are a fundamental part of primary and secondary management of atherosclerotic thrombotic disease including stroke, acute myocardial infarction (AMI), acute coronary syndrome (ACS), angina, percutaneous coronary intervention (PCI), cardiac surgery, primary and secondary cardiovascular disease prevention, peripheral vascular diseases, and thrombotic disorders such as atrial fibrillation.
There are several antiplatelet drugs available for use in clinical practice and several under investigation. Antiplatelets and anticoagulants are useful in the treatment and prophylaxis of arterial thrombotic conditions, but must be carefully administered without increasing the risk of bleeding to an unacceptable level.
Management of patients who are receiving antiplatelets and anticoagulants drugs during the perioperative period requires an understanding of the underlying pathology and rationale for their administration, pharmacology and pharmacokinetics, and drug interactions. The risk versus benefit assessment of continuing or discontinuing these drugs should be made bearing in mind the proposed surgery and its inherent risk for bleeding or thrombotic complications as well as decisions relating to appropriate use of general or some form of regional anesthesia.
In the patient requiring urgent surgery, the options to treat an elevated INR are fresh frozen plasma and prothrombin concentrate complex. Vitamin K takes 1-2 days to achieve the target INR and is considered an adjunct in this setting.
therapy with unfractionated heparin or low molecular weight heparin is indicated in patients with a high or intermediate risk of thromboembolism. In general, Coumadin can be restarted on the first post-operative evening at the maintenance dose. Bridging therapy may be used postoperatively until the INR is therapeutic.
Antiplatelet (as aspirin for an example) administration should be stopped only 3-4 days preoperatively, while clopidogrel discontinuing for 5-7 days preoperatively. Ticlopidine stopped 14 days as the longest antiplatelet should be stopped. Shortest time for stoppage belongs to Tirofiban, only stopped for 8 hours.
Today, there are two new antiplatelet agent groups which have been developed for patients at high risk of thrombosis, their benefits in terms of mortality and major cardiovascular events which have been demonstrated; these include P2Y12 receptor blockers that can be administered either intravenous for rapid onset, then oral for prolonged effect as (elinogrel & cangrelor).
Protease-activated receptor-1antagonists (PAR-1 Antagonist) that act on thrombin receptors on the platelets producing a very potent antiplatelet effect, with little bleeding effect because PAR-1 antagonists do not affect thrombin‘s enzymatic activity on fibrin formation and other mechanisms of platelet activation (such as vorapaxer and atopaxar).