Thromboembolic complications

There is an increased risk of post-operative thromboembolic complications in women taking oral contraceptives Ifposs-bte, use of the drug is discontinued at least 4 weeks before a surgical procedure associated with thromboembolism or during prolonged immobilization. 

Warfarin has been the primary oral anticoagulant used in the United States for the past 60 years. Warfarin is the anticoagulant of choice when long-term or extended anticoagulation is required. Warfarin is FDA-approved for the prevention and treatment of VTE, as well as the prevention of thromboembolic complications in patients with myocardial infarction, atrial fibrillation, and heart valve replacement. While very effective, warfarin has a narrow therapeutic index, requiring frequent dose adjustments and careful patient monitoring.15,29... 

The desired outcome depends on the underlying arrhythmia. For example, the ultimate treatment goals of treating AF or atrial flutter are restoring sinus rhythm, preventing thromboembolic complications, and preventing further recurrences. 

Outpatients taking warfarin should be questioned about medication adherence and symptoms related to bleeding and thromboembolic complications. Any changes in concurrent medications should be carefully explored. 

Thromboembolic complications Adjunct to coumarin anticoagulants in the prevention of postoperative thromboembolic complications of cardiac valve replacement. 

When neuraxial anesthesia (epidural/spinal anesthesia) or spinal puncture is employed, patients who are anticoagulated or scheduled to be anticoagulated with low molecular weight heparins (LMWHs) or heparinoids for prevention of thromboembolic complications are at risk of developing an epidural or spinal hematoma, which can result in long-term or permanent paralysis. 

Abdominal surgery In patients undergoing abdominal surgery with a risk of thromboembolic complications, administer 2,500 units subcutaneously once daily, starting 1 to 2 hours prior to surgery and repeat once daily for 5 to 10 days postoperatively. 

Abdominal surgery In adults at risk for thromboembolic complications, administer 40 mg once daily subcutaneously with the initial dose given 2 hours prior to surgery. The usual duration of administration is 7 to 10 days, up to 12 days. 

Medical patients during acute illness In medical patients at risk for thromboembolic complications due to severely restricted mobility during acute illness, the recommended dose is 40 mg once daily subcutaneously. The usual duration of administration is 6 to 11 days up to 14 days have been well tolerated. 

White clot syndrome - Rarely, patients may develop new thrombus formation in association with thrombocytopenia resulting from irreversible aggregation of platelets induced by heparin, the so-called white clot syndrome. The process may lead to severe thromboembolic complications. Monitor platelet counts before and during therapy. If significant thrombocytopenia occurs, immediately... 

Prophylaxis and/or treatment of the thromboembolic complications associated with atrial fibrillation and/or cardiac valve replacement. 

Thrombocytopenia, heparin-induced For anticoagulation in patients with heparin-induced thrombocytopenia (HIT) and associated thromboembolic disease in order to prevent further thromboembolic complications. 

Heparin-induced thrombocytopenia and associated thromboembolic disease to prevent further thromboembolic complications IV, IV Infusion 0.2-0.4 mg/kg, IV slowly over 15-20 sec, followed by IV infusion of 0.1-0.15 mg/kg/hr for 2-10 days or longer. Dosaye in renal impairment Initial dose is decreased to 0.2 mg/kg, with infusion rate adjusted based on creatinine clearance. 

In clinical trials the cumulative risk of death 35 days after starting treatment was 9% in the lepirudin-treated patients, compared with 18% in historical controls cumulative risk of new thromboembolic complications was 6% with lepirudin and 22% in historical controls... 

Mechanism of Action A coumarin derivative that interferes with hepatic synthesis of vitamin K-dependent clotting factors, resulting in depletion of coagulation factors II, VII, IX, and X. Therapeutic Effect Prevents further extension of formed existing clot prevents new clot formation or secondary thromboembolic complications. Pharmacokinetics ... 

E. Therapeutic response Thrombin-dependent tests show dose dependency [aPTT rise proportionally to dose of Refludan]. The key criteria of efficacy in two pivotal clinical trials from a laboratory standpoint were platelet recovery and effective anticoagulation. Seven days after the start of treatment with Refludan in patients with HIT, the cumulative risk of death, limb amputation, or new thromboembolic complication was substantially lower than in a historical control group. 

Congenital deficiency of Factor XII is inherited as an autosomal recessive trait. Deficiency of this factor is rarely associated with any coagulopathy. It has been observed that people deficient in this factor may have an increased frequency of thromboembolic complications. 

Anticoagulants are sometimes used in the overall treatment of PVE even though there are risks of intracerebral hemorrhage or hemorrhagic infarction. Countering this risk, however, is the risk of major thromboembolic complications involving the central nervous system that may occur in die absence of continued anticoagulant therapy. 

The risk of thromboembolic complications when diethylstilbestrol is used in treating prostatic cancer is well documented, but there has been some doubt as to the mechanisms involved. Oral diethylstilbestrol diphosphate 300 mg/day has been compared with LR-RH agonist therapy or no treatment in 35 patients with prostatic cancer (5). Diethylstilbestrol reduced the concentrations of protein S to below the lower limit of normal in 24 of the 35 cases. There was also some reduction in antithrombin III concentrations. These results were consistently confirmed in a follow-up group of eight further patients who took diethylstilbestrol. Since these very low concentrations of protein S are virtually the same as those found in congenital deficiency, it seems likely that this plays a role in the development of cardiovascular complications during diethylstilbestrol treatment. 

Much of the evidence on the occurrence of thromboembolic complications with oral contraceptives or hormone replacement therapy has been gathered from European or American populations, and it can be helpful to identify data from other parts of the world, where factors such as... 

Women of blood group O have less of a risk of thromboembolism (15). The risk of thromboembolic complications... 

One of the most serious aspects of the thromboembolic complications now widely acknowledged as being associated with HRT is that their emergence coincides with the development of the conclusion that the role of HRT in reducing the risk of coronary heart disease is at best unproven. A form of treatment that was originally viewed as potentially beneficial to the cardiovascular system is at present on balance perhaps harmful (33). 

The use of tamoxifen to prevent breast cancer has been reviewed (8). The merits of using tamoxifen to prevent mammary carcinoma in women who have never had the disease but are believed to be at high risk have been disputed (9), but it is clear that it would involve very long treatment and that one s view of the adverse effects might need to be revised for this class of users. The available data after 5,10, and 15 years of follow up confirmed an increase in the incidence of endometrial cancer and of thromboembolic complications and suggested ocular toxicity, but these effects were not common and should be more than balanced by the reduced risk of coronary heart disease and osteoporosis (8). 

There are isolated reports of thromboembolic complications in recipients of desmopressin most occurred in patients with pre-existing vascular disease. However, in nine trials of the hemostatic efficacy of desmopressin in reducing blood and transfusion requirements in 763 patients, there were no significant differences between the frequencies of thromboembolism in subjects treated with desmopressin and controls (33). An analysis of 31 clinical trials of desmopressin in patients undergoing cardiac, vascular, orthopedic, or other major surgery showed that desmopressin did not increase the incidence of thrombosis (34). 

Most of the reported thromboembolic complications occurred in elderly patients and desmopressin should not be used in patients with documented arterial disease or even in elderly patients, in whom some degree of latent arterial disease may be assumed to be present (34). Concomitant use of antifibrinolytic agents, such as tra-nexamic acid, should also be avoided. 

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