Oral Anticoagulation Therapy (oral + anticoagulation_therapy)

Distribution by Scientific Domains

Selected Abstracts

A comparison of the , -D-xyloside, odiparcil, to warfarin in a rat model of venous thrombosis

Summary,Background:,A significant need exists for new chronic oral anticoagulation therapies to replace warfarin. Previous studies have shown that , -D-xylosides, which prime glycosaminoglycan (GAG) synthesis, have antithrombin and antithrombotic activity. In the following report, a new orally active , -D-xyloside (odiparcil) has been characterized in a rat model of venous thrombosis and its efficacy and bleeding liability compared to warfarin. Additionally, studies were conducted to investigate odiparcil's ex vivo antithrombin and antiplatelet activity, and also to explore the potential utility of protamine sulfate as a neutralizing agent. Methods and results:,In vivo thrombosis studies were conducted in a rat inferior vena cava model, and bleeding studies in a rat tail transection model. Following oral dosing, warfarin and odiparcil produced dose-related suppression of thrombus formation. A therapeutically relevant dose of warfarin in this model (international normalized ratio; INR 3.0) achieved ,65% inhibition of thrombus formation. Warfarin caused dose-related significant increases in bleeding indices. Odiparcil antithrombotic activity was limited by its mechanism to a maximum suppression of thrombus formation of 65,70%, and did not prolong bleeding indices. Additionally, odiparcil-induced heparin cofactor II (HCII)-dependent antithrombin activity was shown to be a function of dermatan sulfate-like GAG production. Other than thrombin-related effects, no odiparcil effects on platelet function were observed. In antidote studies, it was demonstrated that odiparcil-induced antithrombotic activity could be partially neutralized by protamine sulfate. Conclusions:,These experiments suggest that an antithrombotic approach based upon xyloside induction of circulating GAGs may have the potential to approximate the efficacy of warfarin and yet with a reduced risk to hemostasis. [source]

Protein C and protein S levels can be accurately determined within 24 hours of diagnosis of acute venous thromboembolism

Summary In the 50% of cases of acute idiopathic venous thromboembolism, laboratory testing for inherited causes is often performed. Most physicians are under the impression that assays for protein C and protein S should not be measured at the time of diagnosis because of a high false positive rate. We performed a prospective cohort study from two outpatient thromboembolism clinics on consecutive patients with an objectively confirmed diagnosis of first acute idiopathic venous thromboembolism. Assays for protein C and protein S were performed prior to the initiation of oral anticoagulation therapy and within 24 h of diagnosis of venous thromboembolism. Abnormal results were repeated when patients discontinued oral anticoagulant therapy. Of 253 patients tested for both protein C and protein S, 229 (91%; 95% confidence interval 87,94%) were negative and 484 of 508 (95%) tests were normal. Of the 24 initial abnormal results, 21 were repeated and 10 (48%; 95% confidence interval 26,70%) were still abnormal. Overall, 97.8% of initial protein C and protein S results were accurate. If protein C and protein S are measured at the time of diagnosis of acute venous thromboembolism, the majority of the results will be normal and false positives are uncommon. [source]

Managing oral anticoagulation therapy: improving clinical outcomes.

A review
Summary Many physicians are reluctant to prescribe oral anticoagulation therapy (OAT) because of the fear of haemorrhagic complications. Changes in patient health, lifestyle or diet and other drugs can alter the effectiveness of oral anticoagulants. These potential interferences, added to the fact that each individual has a different reaction to these drugs, requires that therapy is monitored regularly. This article aims to review those strategies which help to achieve optimal anticoagulation control and improve the outcomes of OAT. Relevant articles were identified through a search of MEDLINE and included publications reporting on intensity of anticoagulation, the initiation of therapy and the role of pharmacogenetics, the transition from primary to secondary care, management by specialized clinics using decision support software and home-testing. Implementation of these strategies would increase the use of oral anticoagulants by physicians and offers the potential to improve patient safety and reduce adverse events. [source]

Managing oral anticoagulation therapy by pharmacists in a specialty heart hospital

Binita Patel-Naik PharmD MS
First page of article [source]

Non-traumatic pulmonary haematoma complicating oral anticoagulation therapy

RESPIROLOGY, Issue 4 2007
Abstract: Several cases of non-traumatic pulmonary haematoma have been reported in the literature. However, very few of them are related to anticoagulation therapy. The authors report two cases of pulmonary haematoma caused by oral anticoagulant therapy without any underlying pathological lesion. The evolution was fatal in the first case, whereas a slow spontaneous resolution of the haematoma was noted in the second. Non-traumatic pulmonary haematoma can be a complication of oral anticoagulation and should be considered in the differential diagnosis of pulmonary densities in this setting. [source]

What influence do anticoagulants have on oral implant therapy?

A systematic review
Abstract Objectives: This systematic review aims to assess the risks (both thromboembolic and bleeding) of an oral anticoagulation therapy (OAT) patient undergoing implant therapy and to provide a management protocol to patients under OAT undergoing implant therapy. Material and methods: Medline, Cochrane Data Base of Systematic Reviews, the Cochrane Central Register of Controlled Trials and EMBASE (from 1980 to December 2008) were searched for English-language articles published between 1966 and 2008. This search was completed by a hand research accessing the references cited in all identified publications. Results: Nineteen studies were identified reporting outcomes after oral surgery procedures (mostly dental extractions in patients on OAT following different management protocols and haemostatic therapies). Five studies were randomized-controlled trials (RCTs), 11 were controlled clinical trials (CCTs) and three were prospective case series. The OAT management strategies as well as the protocols during and after surgery were different. This heterogeneity prevented any possible data aggregation and synthesis. The results from these studies are very homogeneous, reporting minor bleeding in very few patients, without a significant difference between the OAT patients who continue with the vitamin K antagonists vs. the patients who stopped this medication before surgery. These post-operative bleeding events were controlled only with local haemostatic measures: tranexamic acid mouthwashes, gelatine sponges and cellulose gauzes's application were effective. Post-operative bleeding did not correlate with the international normalised ratio (INR) status. In none of the studies was a thromboembolic event reported. Conclusions: OAT patients (INR 2,4) who do not discontinue the AC medication do not have a significantly higher risk of post-operative bleeding than non-OAT patients and they also do not have a higher risk of post-operative bleeding than OAT patients who discontinue the medication. In patients with OAT (INR 2,4) without discontinuation, topical haemostatic agents were effective in preventing post-operative bleeding. OAT discontinuation is not recommended for minor oral surgery, such as single tooth extraction or implant placement, provided that this does not involve autogenous bone grafts, extensive flaps or osteotomy preparations extending outside the bony envelope. Evidence does not support that dental implant placement in patients on OAT is contraindicated. [source]