Disorders of Hemostasis

BACKGROUND: Consensus recommendations for acute acetaminophen exposure include plotting an acetaminophen concentration at ≥ 4 h post ingestion on the Rumack-Matthew nomogram to determine the need for acetylcysteine treatment. We studied the frequency of acetaminophen concentrations drawn within 4 h post ingestion and whether the Rumack-Matthew nomogram was properly used in making acetylcysteine treatment decisions. METHODS: This was a retrospective, observational case series at three regional poison centers of acute acetaminophen exposures between 1/1/13 and 12/31/13...

INTRODUCTION: Patients with hemophilia now have a life expectancy very close to that of the unaffected male population and, hence, are at risk of developing the classic age-related morbidities, i.e., cardiovascular diseases. The peculiarity of the management of these diseases in hemophilia is that antithrombotic drugs impinge on the already compromised hemostasis of these lifelong bleeders. AREAS COVERED: This opinion article outlines the strategies we have developed, based on our clinical experience, for the antithrombotic treatment of two common cardiovascular diseases - acute coronary syndromes and chronic atrial fibrillation - in patients with hemophilia A and B...

BACKGROUND: Physicians reverse patients' warfarin anticoagulation with frozen plasma or prothrombin complex concentrate. Our objective was to determine adverse event frequency after urgent reversal with frozen plasma versus the prothrombin complex concentrate Octaplex. METHODS AND RESULTS: This natural before-after retrospective cohort study in 2 tertiary care emergency departments compared anticoagulation reversal with frozen plasma (September 2006-August 2008) and with Octaplex (September 2008-August 2010), without other system changes...

The diagnosis of disseminated intravascular coagulation (DIC) should encompass both clinical and laboratory information. The International Society for Thrombosis and Haemostasis (ISTH) DIC scoring system provides objective measurement of DIC. Where DIC is present the scoring system correlates with key clinical observations and outcomes. It is important to repeat the tests to monitor the dynamically changing scenario based on laboratory results and clinical observations. The cornerstone of the treatment of DIC is treatment of the underlying condition...

BACKGROUND: Warfarin reduces the risk of stroke in patients with atrial fibrillation but increases the risk of hemorrhage and is difficult to use. Dabigatran is a new oral direct thrombin inhibitor. METHODS: In this noninferiority trial, we randomly assigned 18,113 patients who had atrial fibrillation and a risk of stroke to receive, in a blinded fashion, fixed doses of dabigatran--110 mg or 150 mg twice daily--or, in an unblinded fashion, adjusted-dose warfarin...

INTRODUCTION: Dabigatran (Pradaxa™), an orally active direct thrombin inhibitor, was approved by the United States Food and Drug Administration for the prevention of stroke in patients with atrial fibrillation in October 2010. Life-threatening consequences from dabigatran therapy include hemorrhage and bleeding complications, but they typically occur after renal impairment. We describe the first case report of intentional, acute overdose with dabigatran. CASE REPORT: A 57-year-old woman with a medical history of depression and atrial fibrillation presented to the emergency department after ingesting 11...

Type 2B von Willebrand disease (VWD) accounts for fewer than 5% of all VWD patients. In this disease, mutations in the A1 domain result in increased von Willebrand factor (VWF) binding to platelet GPIbα receptors, causing increased platelet clearance and preferential loss of high molecular weight VWF multimers. Diagnosis is complicated because of significant clinical variations even among patients with identical mutations. Platelet transfusion often provides suboptimal results since transfused platelets may be aggregated by the patients' abnormal VWF...

OBJECTIVE: Epistaxis is a common problem in the emergency department (ED). Sixty percent of people experience it at least once in their life. There are different kinds of treatment for epistaxis. This study intended to evaluate the topical use of injectable form of tranexamic acid vs anterior nasal packing with pledgets coated with tetracycline ointment. METHODS: Topical application of injectable form of tranexamic acid (500 mg in 5 mL) was compared with anterior nasal packing in 216 patients with anterior epistaxis presented to an ED in a randomized clinical trial...

Rivaroxaban is an oral, direct factor Xa inhibitor for the management of thromboembolic disorders. Despite its short half-life, the ability to reverse rivaroxaban anticoagulation could be beneficial in life-threatening emergencies. The potential of prothrombin complex concentrate (PCC; Beriplex®), activated PCC (aPCC; FEIBA®) or recombinant activated factor VII (rFVIIa; NovoSeven®) to reverse rivaroxaban in rats and baboons was investigated. Anaesthetised rats pre-treated with intravenous rivaroxaban (2 mg/kg) received intravenous rFVIIa (100/400 μg/kg), PCC (25/50 U/kg) or aPCC (50/100 U/kg) after initiation of bleeding...

No abstract text is available yet for this article.

The new oral anticoagulants dabigatran, rivaroxaban and apixaban have advantages over warfarin which include no need for laboratory monitoring, less drug-drug interactions and less food-drug interactions. However, there is no established antidote for patients who are bleeding or require emergent surgery and there is a paucity of evidence to guide the clinical care during these situations. Members of thrombosis and anticoagulation groups participating in the Thrombosis and Hemostasis Summit of North America formulated expert opinion guidance for reversing the anticoagulant effect of the new oral anticoagulants and suggest: routine supportive care, activated charcoal if drug ingestion was within a couple of hours, and hemodialysis if feasible for dabigatran...

BACKGROUND: Thrombolytic treatment with intravenous tissue plasminogen activator (i.v. tPA) is the only FDA-approved therapy for acute ischemic stroke. There are risks associated with thrombolytics, including intracranial and extracranial hemorrhage and hypersensitivity reactions. Established treatment for post-tPA hemorrhage includes administration of blood products including cryoprecipitate, fresh frozen plasma, and platelets which have poorly established efficacy. Tranexamic acid (TXA) and epsilon-aminocaproic acid (EACA) have been studied as hemostatic therapies in post-operative hemorrhage, menorrhagia, intracranial hemorrhage (ICH), subarachnoid hemorrhage, and trauma patients...

BACKGROUND: Tranexamic acid reduces haemorrhage through its antifibrinolytic effects. In a previous version of the present review, we found that tranexamic acid may reduce mortality. The present review includes updated searches of randomised trials on tranexamic acid versus placebo, cimetidine or lansoprazole. OBJECTIVES: To assess the effects of tranexamic acid for upper gastrointestinal bleeding. SEARCH METHODS: Electronic searches (The Cochrane Library, MEDLINE, EMBASE, Science Citation Index) and manual searches were combined...

Heparin is a widely used anticoagulant. Because of its negative charge, it forms complexes with positively charged platelet factor 4 (PF4). This can induce anti-PF4/heparin IgG Abs. Resulting immune complexes activate platelets, leading to the prothrombotic adverse drug reaction heparin-induced thrombocytopenia (HIT). HIT requires treatment with alternative anticoagulants. Approved for HIT are 2 direct thrombin inhibitors (DTI; lepirudin, argatroban) and danaparoid. They are niche products with limitations...

BACKGROUND: Rivaroxaban and dabigatran are new oral anticoagulants that specifically inhibit factor Xa and thrombin, respectively. Clinical studies on the prevention and treatment of venous and arterial thromboembolism show promising results. A major disadvantage of these anticoagulants is the absence of an antidote in case of serious bleeding or when an emergency intervention needs immediate correction of coagulation. This study evaluated the potential of prothrombin complex concentrate (PCC) to reverse the anticoagulant effect of these drugs...

No abstract text is available yet for this article.

Evidence-based guidelines recommend that heparin-induced thrombocytopenia (HIT) should be suspected whenever a patient develops thrombosis or thrombocytopenia 5 to 14 days after heparin initiation. The authors determined how frequently emergency department (ED) physicians document HIT risk assessment in patients presenting with thrombosis. Relevant data were extracted from the ED charts of 134 patients with venous or arterial thrombosis. Documentation (ie, notation of positive or negative findings) existed for recent heparin exposure in 7 (5...

Dabigatran etexilate is an oral, reversible direct thrombin inhibitor that is approved in the EU and several other countries for the prevention of venous thromboembolism after elective hip and knee replacement, and is in advanced clinical development for other thromboembolic disorders. Dabigatran has a predictable pharmacokinetic profile, allowing for a fixed-dose regimen without the need for routine coagulation monitoring. In certain clinical situations such as serious bleeding into critical organs (e.g. intracerebral bleeding), potential overdose and emergency surgery, clinicians will need to make an assessment of the anticoagulant status of a patient receiving dabigatran before deciding on future management strategies...

Although there is no need for routine coagulation monitoring with rivaroxaban--an oral, direct factor Xa inhibitor--a haemostasis assay might be valuable to measure its pharmacodynamic effects. This study aimed to find assays, among those commercially available, to measure rivaroxaban pharmacodynamics. Several global conventional clotting tests, as well as clotting or chromogenic assays to measure anti-factor Xa activity, were studied. A thrombin generation test using calibrated automated thrombogram was also done...

OBJECTIVE: Mild hypothermia (32-35 degrees C) impairs primary haemostasis and coagulation. Correction of these haemostatic impairments by rewarming alone may not be possible or desirable, particularly in major trauma, neuroanaesthesia and in critically ill patients. Pharmacological treatment of these impairments, if available, may be a useful alternative. Desmopressin has been used to treat various congenital and acquired platelet disorders, but its effects on hypothermia-induced impairment of primary haemostasis is not known...