vitamin-k-semiquinone-radical and Thrombocytopenia

Central venous catheter (CVC) placement increases the risk of thrombosis in people with cancer. Thrombosis often necessitates the removal of the CVC, resulting in treatment delays and thrombosis-related morbidity and mortality. This is an update of the Cochrane Review published in 2014.. To evaluate the efficacy and safety of anticoagulation for thromboprophylaxis in people with cancer with a CVC.. We conducted a comprehensive literature search in May 2018 that included a major electronic search of Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (Ovid), and Embase (Ovid); handsearching of conference proceedings; checking of references of included studies; searching for ongoing studies; and using the 'related citation' feature in PubMed. This update of the systematic review was based on the findings of a literature search conducted on 14 May 2018.. Randomized controlled trials (RCTs) assessing the benefits and harms of unfractionated heparin (UFH), low-molecular-weight heparin (LMWH), vitamin K antagonists (VKA), or fondaparinux or comparing the effects of two of these anticoagulants in people with cancer and a CVC.. Using a standardized form, we extracted data and assessed risk of bias. Outcomes included all-cause mortality, symptomatic catheter-related venous thromboembolism (VTE), pulmonary embolism (PE), major bleeding, minor bleeding, catheter-related infection, thrombocytopenia, and health-related quality of life (HRQoL). We assessed the certainty of evidence for each outcome using the GRADE approach (Balshem 2011).. Thirteen RCTs (23 papers) fulfilled the inclusion criteria. These trials enrolled 3420 participants. Seven RCTs compared LMWH to no LMWH (six in adults and one in children), six RCTs compared VKA to no VKA (five in adults and one in children), and three RCTs compared LMWH to VKA in adults.LMWH versus no LMWHSix RCTs (1537 participants) compared LMWH to no LMWH in adults. The meta-analyses showed that LMWH probably decreased the incidence of symptomatic catheter-related VTE up to three months of follow-up compared to no LMWH (risk ratio (RR) 0.43, 95% confidence interval (CI) 0.22 to 0.81; risk difference (RD) 38 fewer per 1000, 95% CI 13 fewer to 52 fewer; moderate-certainty evidence). However, the analysis did not confirm or exclude a beneficial or detrimental effect of LMWH on mortality at three months of follow-up (RR 0.82, 95% CI 0.53 to 1.26; RD 14 fewer per 1000, 95% CI 36 fewer to 20 more; low-certainty evidence), major bleeding (RR 1.49, 95% CI 0.06 to 36.28; RD 0 more per 1000, 95% CI 1 fewer to 35 more; very low-certainty evidence), minor bleeding (RR 1.35, 95% CI 0.62 to 2.92; RD 14 more per 1000, 95% CI 16 fewer to 79 more; low-certainty evidence), and thrombocytopenia (RR 1.03, 95% CI 0.80 to 1.33; RD 5 more per 1000, 95% CI 35 fewer to 58 more; low-certainty evidence).VKA versus no VKAFive RCTs (1599 participants) compared low-dose VKA to no VKA in adults. The meta-analyses did not confirm or exclude a beneficial or detrimental effect of low-dose VKA compared to no VKA on mortality (RR 0.99, 95% CI 0.64 to 1.55; RD 1 fewer per 1000, 95% CI 34 fewer to 52 more; low-certainty evidence), symptomatic catheter-related VTE (RR 0.61, 95% CI 0.23 to 1.64; RD 31 fewer per 1000, 95% CI 62 fewer to 51 more; low-certainty evidence), major bleeding (RR 7.14, 95% CI 0.88 to 57.78; RD 12 more per 1000, 95% CI 0 fewer to 110 more; low-certainty evidence), minor bleeding (RR 0.69, 95% CI 0.38 to 1.26; RD 15 fewer per 1000, 95% CI 30 fewer to 13 more; low-certainty evidence), premature catheter removal (RR 0.82, 95% CI 0.30 to 2.24; RD 29 fewer per 1000, 95% CI 114 fewer to 202 more; low-certainty evidence), and catheter-related infection (RR 1.17, 95% CI 0.74 to 1.85; RD 71 more per 1000, 95% CI 109 fewer to 356; low-certainty evidence).LMWH versus VKAThree RCTs (641 participants) compared LMWH to VKA in adults. The available evidence did not confirm or exclude a beneficial or detrimental effect of LMWH relative to VKA on mortality (RR 0.94, 95% CI 0.56 to 1. The evidence was not conclusive for the effect of LMWH on mortality, the effect of VKA on mortality and catheter-related VTE, and the effect of LMWH compared to VKA on mortality and catheter-related VTE. We found moderate-certainty evidence that LMWH reduces catheter-related VTE compared to no LMWH. People with cancer with CVCs considering anticoagulation should balance the possible benefit of reduced thromboembolic complications with the possible harms and burden of anticoagulants.

Topics: Adult; Anticoagulants; Catheter-Related Infections; Catheterization, Central Venous; Child; Heparin; Heparin, Low-Molecular-Weight; Humans; Neoplasms; Randomized Controlled Trials as Topic; Secondary Prevention; Thrombocytopenia; Venous Thrombosis; Vitamin K

Antiphospholipid syndrome (APS), heparin-induced thrombocytopenia, and paroxysmal nocturnal hemoglobinuria are 3 acquired thrombophilias that carry a high risk of venous and arterial thromboembolism. Management of these conditions has largely included anticoagulation with a vitamin K antagonist after an initial period of a parenteral anticoagulant, for as long as the thrombotic risk is still present. The available evidence for the use of direct oral anticoagulants (DOACs) is limited and primarily consists of case series and cohort studies, which are summarized in this chapter. Randomized trials evaluating DOACs in patients with APS are reviewed. Further research is needed prior to widely adopting DOACs for use in these high-risk acquired thrombophilias; however, there may be selected low-risk subgroups where DOAC use is possible after careful consideration and patient discussion.

Topics: Administration, Oral; Anticoagulants; Antiphospholipid Syndrome; Disease Management; Hemoglobinuria, Paroxysmal; Heparin; Humans; Thrombocytopenia; Thrombophilia; Thrombosis; Vitamin K

Antiphospholipid syndrome (APS), heparin-induced thrombocytopenia, and paroxysmal nocturnal hemoglobinuria are 3 acquired thrombophilias that carry a high risk of venous and arterial thromboembolism. Management of these conditions has largely included anticoagulation with a vitamin K antagonist after an initial period of a parenteral anticoagulant, for as long as the thrombotic risk is still present. The available evidence for the use of direct oral anticoagulants (DOACs) is limited and primarily consists of case series and cohort studies, which are summarized in this chapter. Randomized trials evaluating DOACs in patients with APS are reviewed. Further research is needed prior to widely adopting DOACs for use in these high-risk acquired thrombophilias; however, there may be selected low-risk subgroups where DOAC use is possible after careful consideration and patient discussion.

Topics: Administration, Oral; Anticoagulants; Antiphospholipid Syndrome; Hemoglobinuria, Paroxysmal; Heparin; Humans; Patient Education as Topic; Risk Factors; Thrombocytopenia; Thrombophilia; Vitamin K

Cancer associated thrombosis (CAT) is a frequent complication among cancer patients. It is associated with increased morbidity, mortality, and psychological burden. Areas covered: Low-molecular-weight heparin monotherapy for the initial 6 months is considered the standard of care for the acute and long-term management of CAT. For patients at high risk of recurrent CAT (e.g. active cancer or still undergoing anticancer therapy) beyond the initial 6 months of treatment, continuation of anticoagulation therapy for secondary prevention is usually recommended. The management of anticoagulation therapy is more challenging in patients with cancer. Cancer patients are more likely to have recurrent events despite anticoagulation, thrombocytopenia due to their chemotherapy regimens or have incidental pulmonary embolism diagnosed on their staging imaging. Expert commentary: We will review expert consensuses and opinions in order to guide clinicians on how to tailor the management of CAT in these special circumstances.

Topics: Anticoagulants; Disease Management; Heparin, Low-Molecular-Weight; Humans; Neoplasms; Secondary Prevention; Thrombocytopenia; Thrombosis; Time Factors; Vitamin K

Simply providing anticoagulation therapy is not as straightforward of a solution in cancer patients who have concurrent thrombocytopenia owing to the increased risk of bleeding complications. Currently, few guidelines are in place to assist clinicians in safely managing thrombocytopenic cancer patients on anticoagulation. The purpose of this review is to critically examine the available body of biomedical literature surrounding anticoagulant use against the backdrop of cancer-related thrombocytopenia in adult patients. Available evidence for the use of parenteral anticoagulants (low molecular weight heparins, unfractionated heparin, pentasaccharides, and direct thrombin inhibitors) and oral anticoagulants (vitamin K antagonists and novel oral anticoagulants) in thrombocytopenic cancer patients is described. The review revealed many inconsistencies between reports on this topic, which made it difficult to draw firm conclusions as to, for example, the ideal well tolerated anticoagulant dose in thrombocytopenic cancer patients? Intriguingly, critical clinical information including (but not limited) patient platelet nadirs, platelet counts during bleeding episodes, and platelet transfusion support was absent from a not-so-insignificant number of publications. Despite these shortcomings, the review sets out to formulate recommendations on the management of anticoagulation, at prophylactic or treatment doses, in adult cancer patients who also have concurrent thrombocytopenia. It also enlists a call for the medical community, by mapping select clinical guideposts, for further research in this setting. With the inclusion of these criteria in future studies, only then formal recommendations on the ideal safe dosage of anticoagulants in cancer patients, based on solid evidence, are conceived.

Topics: Adult; Anticoagulants; Antithrombins; Blood Coagulation; Blood Platelets; Drug Dosage Calculations; Guidelines as Topic; Hemorrhage; Heparin, Low-Molecular-Weight; Humans; Neoplasms; Platelet Count; Platelet Transfusion; Thrombocytopenia; Vitamin K

Topics: Administration, Oral; Anticoagulants; Female; Heparin; Humans; Male; Thrombocytopenia; Treatment Outcome; Vitamin K

The major practical advantage of the direct oral anticoagulants (DOACs), comprising the thrombin inhibitor dabigatran and the factor Xa inhibitors apixaban, edoxaban, and rivaroxaban, over vitamin K antagonists is their fixed dosing without the need for laboratory monitoring. With the recent, rapid introduction of the DOACs for the treatment of acute venous thromboembolism (VTE), clinicians are now faced with various questions regarding the efficacy and safety of these compounds overall and in specific high-risk populations. The collective evidence from 6 large clinical trials involving 27,000 patients has demonstrated that DOACs are as effective as vitamin K antagonists (VKA) in preventing recurrent VTE while being associated with a significantly lower risk of major bleeding. These findings are consistent in subgroups of patients with pulmonary embolism, the elderly, and those patients with a high body weight or moderate renal insufficiency, making these agents suitable for a broad spectrum of patients with VTE. DOACs are also an attractive treatment option in patients with VTE and concomitant cancer, thrombotic antiphospholipid syndrome, or heparin-induced thrombocytopenia, but the currently available clinical data is insufficient to make evidence-based recommendations on the use of DOACs in these settings. Several studies evaluating the efficacy and safety of DOACs in these high-risk populations are underway.

Topics: Administration, Oral; Anticoagulants; Antiphospholipid Syndrome; Clinical Trials as Topic; Factor Xa Inhibitors; Hemorrhage; Humans; Neoplasms; Pulmonary Embolism; Recurrence; Renal Insufficiency; Risk; Thrombin; Thrombocytopenia; Thrombosis; Treatment Outcome; Venous Thromboembolism; Venous Thrombosis; Vitamin K

Regarding anticoagulant therapies there has been a remarkable shift in recent years. The objective of this brief overview is to provide relevant information and guidelines on the advantages and disadvantages of novel anticoagulants addressing specifically the surgical disciplines. Hitherto, conventional anticoagulant therapy in patients with a high thrombosis risk was largely limited to heparins and vitamin-K antagonists (VKA). Their modes of action, the difficulties in managing VKAs (e.g., bridging therapy) and the risk of HIT (heparin-induced thrombocytopenia) associated with heparins are briefly discussed. Novel anticoagulants supposedly eliminate these obstacles. Fondaparinux (Arixtra®) is a fully synthetic pentasaccharide which acts like a heparin but has an increased half life. Fondaparinux has a diminished risk of HIT. However, no specific antidote is currently available for Fondaparinux. The novel oral anticoagulants (NOAC) dabigatran etexilat (Pradaxa®), rivaroxaban (Xarelto®) and apixaban (Eliquis®), also known as "direct" anticoagulants, act independently from antithrombin by inhibiting thrombin, as in the case of dabigatran, or by inhibiting factor Xa, as in the case of rivaroxaban and apixaban. It is assumed that they are suitable for long-term use and do not require laboratory monitoring. Nevertheless, clinical experience is very limited and caution rather than quick conclusions is necessary. Two major drawbacks are on the one hand the risk of drug accumulation in kidney and/or liver disease and, on the other hand, the lack of specific antidotes. In addition, interactions with other medication may have unexpected effects on serum drug levels. Therefore, the analysis of drug levels in the plasma may become necessary in subgroups of patients.. Studies establishing clear recommendations for the desirable and measurable reference range are needed. Similarly, evidence-based recommendations regarding perioperative prevention of thrombosis are required ("bridging": yes or no?). Irrespective of these issues, the authors predict a further expansion of the use of NOACs.

Topics: Administration, Oral; Anticoagulants; Benzimidazoles; Blood Coagulation Tests; Dabigatran; Drug Interactions; Factor Xa Inhibitors; Fondaparinux; Heparin; Humans; International Normalized Ratio; Liver Failure; Metabolic Clearance Rate; Morpholines; Perioperative Care; Polysaccharides; Pyrazoles; Pyridines; Pyridones; Renal Insufficiency; Rivaroxaban; Thiophenes; Thrombocytopenia; Thrombosis; Vitamin K

Topics: Antibodies; Anticoagulants; Antithrombins; Arthroplasty, Replacement, Knee; Chondroitin Sulfates; Dermatan Sulfate; Fondaparinux; Heparin; Heparin, Low-Molecular-Weight; Heparitin Sulfate; Humans; Immunoglobulin G; Male; Middle Aged; Platelet Activation; Platelet Count; Platelet Factor 4; Polysaccharides; Practice Guidelines as Topic; Thrombocytopenia; Venous Thrombosis; Vitamin K

Heparin-induced thrombocytopenia (HIT) is an antibody-mediated adverse drug reaction that can lead to devastating thromboembolic complications, including pulmonary embolism, ischemic limb necrosis necessitating limb amputation, acute myocardial infarction, and stroke.. The methods of this guideline follow the Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement.. Among the key recommendations for this article are the following: For patients receiving heparin in whom clinicians consider the risk of HIT to be > 1%, we suggest that platelet count monitoring be performed every 2 or 3 days from day 4 to day 14 (or until heparin is stopped, whichever occurs first) (Grade 2C). For patients receiving heparin in whom clinicians consider the risk of HIT to be < 1%, we suggest that platelet counts not be monitored (Grade 2C). In patients with HIT with thrombosis (HITT) or isolated HIT who have normal renal function, we suggest the use of argatroban or lepirudin or danaparoid over other nonheparin anticoagulants (Grade 2C). In patients with HITT and renal insufficiency, we suggest the use of argatroban over other nonheparin anticoagulants (Grade 2C). In patients with acute HIT or subacute HIT who require urgent cardiac surgery, we suggest the use of bivalirudin over other nonheparin anticoagulants or heparin plus antiplatelet agents (Grade 2C).. Further studies evaluating the role of fondaparinux and the new oral anticoagulants in the treatment of HIT are needed.

Topics: Anticoagulants; Drug Therapy, Combination; Evidence-Based Medicine; Fibrinolytic Agents; Heparin; Humans; International Normalized Ratio; Platelet Count; Risk Factors; Societies, Medical; Thrombocytopenia; Thromboembolism; Thrombosis; United States; Vitamin K

Topics: Anticoagulants; Antifibrinolytic Agents; Antithrombins; Biological Availability; Drug Monitoring; Drug-Related Side Effects and Adverse Reactions; Hemorrhage; Heparin; Humans; Thrombocytopenia; Thrombosis; Vitamin K

The continuing education course "Hemostasis" provided a comprehensive review of hemostasis and selected perturbations of the underlying processes as well as an assessment of hemostasis in animal models and preclinical testing environments. The session began with a review of the current state of understanding of hemostasis and how the waterfall or cascade of activation has transformed to the current cell-based, membrane-associated sequence of highly regulated events. The specific mechanisms of drug-induced thrombocytopenia were then presented, followed by a discussion of the relationships of coagulation and platelets in inflammation and cancer metastasis and platelet activity. Evaluation of hemostasis and platelet function in animals and especially in the environment of the contract research facility concluded the session.

Topics: Animals; Blood Coagulation; Blood Coagulation Disorders; Blood Platelets; Education, Continuing; Hemostasis; Humans; Inflammation; Models, Animal; Neoplasm Metastasis; Platelet Activation; Platelet Aggregation; Thrombocytopenia; Vitamin K

The aim of medicinal treatment, during and after femoral and crural interventions is to prevent early or late onset arterial thrombosis of the treated vascular segments. Therefore, unfractionated heparin is administered during the intervention by an intra-arterial or intravenous approach. To avoid late onset thrombosis, administration of platelet function inhibitors is recommended. However, valid data are only available for acetylsalicylic acid (ASA). Therefore, ASA is recommended for long term medication. In several cardiological studies on stent implantation in coronary vessels the combination of ASA and clopidogrel for dual platelet inhibition has been proven to be effective. These results have been transferred to antithrombotic therapy of the lower extremities despite the lack of dedicated studies. There is no evidence for the use of vitamin K antagonists after peripheral interventions.

Topics: Administration, Oral; Anticoagulants; Arterial Occlusive Diseases; Aspirin; Clopidogrel; Drug Therapy, Combination; Heparin; Humans; Infusions, Intravenous; Ischemia; Leg; Long-Term Care; Platelet Aggregation Inhibitors; Randomized Controlled Trials as Topic; Secondary Prevention; Thrombocytopenia; Thrombosis; Ticlopidine; Vitamin K

Inflammatory plaques at injection sites are frequent side effects of heparin treatment and a clinical symptom of delayed-type hypersensitivity (DTH) to heparin. In most cases, changing the subcutaneous therapy from unfractionated to low-molecular-weight heparin or treatment with heparinoids does not provide improvement because of extensive cross-reactivity. Because of their completely different chemical structure, hirudins are a safe alternative for anticoagulation. Despite DTH to subcutaneously injected heparins, patients tolerate heparin intravenously. Therefore, in case of therapeutic necessity and DTH to heparins, the simple shift from subcutaneous to intravenous heparin administration is justified. Skin necrosis is a rare complication of anticoagulation. Heparin-induced skin necrosis is 1 of the symptoms of immune-mediated heparin-induced thrombocytopenia and should result in the immediate cessation of heparin therapy to prevent potentially fatal thrombotic events. This is in contrast to coumarin-induced skin necrosis, where therapy may be continued or restarted at a lower dose.

Topics: Anaphylaxis; Anticoagulants; Coumarins; Drug Eruptions; Fibrinolytic Agents; Fondaparinux; Heparin; Heparin, Low-Molecular-Weight; Hirudins; Humans; Hypersensitivity, Delayed; Polysaccharides; Thrombin; Thrombocytopenia; Vitamin K

For a majority of patients with venous thromboembolism (VTE), initial treatment is straightforward and necessitates the immediate initiation of a parenteral anticoagulant (eg, heparin or low molecular weight heparin), simultaneous initiation of long-term therapy (eg, vitamin K antagonist), and discontinuation of the parenteral anticoagulant after 5 days assuming that the vitamin K antagonist is therapeutic. This standardized approach is based on numerous pivotal clinical trials completed over the past 3 decades. Yet, advances in standardized VTE treatment continue to evolve and include issues related to the selection and dosing of parenteral anticoagulants (eg, relative efficacy and dosing in the obese patient, patients with renal impairment, and pregnant patients), optimal location of initial care delivery, use of dosing initiation nomograms for vitamin K antagonists with the potential of gene-based dosing, and demonstration that longterm low molecular weight heparin therapy may be optimal for some patient populations (eg, those with active cancer). Further, in parallel with the evolution of VTE treatment, there have been remarkable advances in our understanding of heparin-induced thrombocytopenia, a prothrombotic complication of parenteral anticoagulant use.

Topics: Heparin; Heparin, Low-Molecular-Weight; Humans; Thrombocytopenia; Venous Thromboembolism; Vitamin K; Warfarin

Heparin-induced thrombocytopenia (HIT) is an immune-mediated disorder caused by the development of antibodies to platelet factor 4 (PF4) and heparin. The thrombocytopenia is typically moderate, with a median platelet count nadir of approximately 50 to 60 x 10(9) platelets/L. Severe thrombocytopenia has been described in patients with HIT, and in these patients antibody levels are high and severe clinical outcomes have been reported (eg, disseminated intravascular coagulation with microvascular thrombosis). The timing of the thrombocytopenia in relation to the initiation of heparin therapy is critically important, with the platelet count beginning to drop within 5 to 10 days of starting heparin. A more rapid drop in the platelet count can occur in patients who have been recently exposed to heparin (within the preceding 3 months), due to preformed anti-heparin/PF4 antibodies. A delayed form of HIT has also been described that develops within days or weeks after the heparin has been discontinued. In contrast to other drug-induced thrombocytopenias, HIT is characterized by an increased risk for thromboembolic complications, primarily venous thromboembolism. Heparin and all heparin-containing products should be discontinued and an alternative, non-heparin anticoagulant initiated. Alternative agents that have been used effectively in patients with HIT include lepirudin, argatroban, bivalirudin, and danaparoid, although the last agent is not available in North America. Fondaparinux has been used in a small number of patients with HIT and generally appears to be safe. Warfarin therapy should not be initiated until the platelet count has recovered and the patient is systemically anticoagulated, and vitamin K should be administered to patients receiving warfarin at the time of diagnosis of HIT.

Topics: Anticoagulants; Arginine; Autoantibodies; Contraindications; Disseminated Intravascular Coagulation; Fondaparinux; Heparin; Hirudins; Humans; Pipecolic Acids; Platelet Count; Platelet Factor 4; Polysaccharides; Recombinant Proteins; Sulfonamides; Thrombocytopenia; Thrombophilia; Time Factors; Venous Thromboembolism; Vitamin K; Warfarin

Accomplishing a successful percutaneous coronary intervention in a patient with a suspected or diagnosed heparin-induced thrombocytopenia (HIT) requires the selection of an appropriate alternative anticoagulant and a thorough assessment of bleeding and thrombotic risks. In this review, we suggest an evidence-based management algorithm that takes into account the clinical phase of HIT (acute, recent, and remote HIT) and the associated risk when patients present with acute coronary syndrome. The algorithm also integrates preventive measures directed at decreasing the bleeding risk associated with the antithrombotic and invasive therapies used for HIT and percutaneous coronary intervention.

Topics: Algorithms; Angioplasty, Balloon, Coronary; Anticoagulants; Arginine; Chondroitin Sulfates; Comorbidity; Dermatan Sulfate; Drug Therapy, Combination; Fibrinolytic Agents; Fondaparinux; Heparin; Heparinoids; Heparitin Sulfate; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Pipecolic Acids; Polysaccharides; Recombinant Proteins; Sulfonamides; Syndrome; Thrombocytopenia; Vitamin K

Anticoagulation is highly effective in the prevention and treatment of venous thromboembolism (VTE). Since decades, vitamin K antagonists (VKA) were the only available oral anticoagulants. Even though VKA are very effective, they have numerous practical problems: Due to their narrow therapeutic window, highly variable dose requirements and drug interactions, close monitoring is mandatory, aiming towards an INR of 2-3 for most indications. At present, new oral anticoagulants are being studied, such as the oral direct thrombin inhibitor Ximelagatran, which in trials for prevention and treatment of VTE appears at least equivalent to heparin and VKA. Heparins have to be administered parenterally, and low molecular-weight heparins have been able to overcome some of the shortcomings of standard heparins, such as limited bioavailability, variable dose response and heparin induced thrombocytopenia (HIT). Heparinoids and hirudins are alternative anticoagulants to treat HIT. With the development of synthetic pentasaccharides, such as Fondaparinux an increase in efficacy could be achieved in high-risk thromboprophylaxis.

Topics: Anticoagulants; Azetidines; Benzylamines; Dose-Response Relationship, Drug; Drug Therapy; Evidence-Based Medicine; Fondaparinux; Heparin; Humans; Patient Care Management; Polysaccharides; Practice Patterns, Physicians'; Thrombocytopenia; Treatment Outcome; Venous Thrombosis; Vitamin K

This chapter about the recognition, treatment, and prevention of heparin-induced thrombocytopenia (HIT) is part of the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy: Evidence Based Guidelines. Grade 1 recommendations are strong and indicate that the benefits do, or do not, outweigh risks, burden, and costs. Grade 2 suggests that individual patients' values may lead to different choices (for a full understanding of the grading, see Guyatt et al, CHEST 2004; 126:179S-187S). Among the key recommendations in this chapter are the following: For patients in whom the risk of HIT is considered to be > 0.1%, we recommend platelet count monitoring (Grade 1C). For patients who are receiving therapeutic-dose unfractionated heparin (UFH), we suggest at least every-other-day platelet count monitoring until day 14, or until UFH is stopped, whichever occurs first (Grade 2C). For patients who are receiving postoperative antithrombotic prophylaxis with UFH (HIT risk > 1%), we suggest at least every-other-day platelet count monitoring between postoperative days 4 to 14 (or until UFH is stopped, whichever occurs first) [Grade 2C]. For medical/obstetric patients who are receiving prophylactic-dose UFH, postoperative patients receiving prophylactic-dose low molecular weight heparin (LMWH), postoperative patients receiving intravascular catheter UFH "flushes," or medical/obstetrical patients receiving LMWH after first receiving UFH (risk, 0.1 to 1%), we suggest platelet count monitoring every 2 days or 3 days from day 4 to day 14, or until heparin is stopped, whichever occurs first (Grade 2C). For medical/obstetrical patients who are only receiving LMWH, or medical patients who are receiving only intravascular catheter UFH flushes (risk < 0.1%), we suggest clinicians do not use routine platelet count monitoring (Grade 2C). For patients with strongly suspected (or confirmed) HIT, whether or not complicated by thrombosis, we recommend use of an alternative anticoagulant, such as lepirudin (Grade 1C+), argatroban (Grade 1C), bivalirudin (Grade 2C), or danaparoid (Grade 1B). For patients with strongly suspected (or confirmed) HIT, we recommend routine ultrasonography of the lower-limb veins for investigation of deep venous thrombosis (Grade 1C); against the use of vitamin K antagonist (VKA) [coumarin] therapy until after the platelet count has substantially recovered; that the VKA antagonist be administered only during overlapping alternative anticoagulation (m

Topics: Dose-Response Relationship, Drug; Drug Monitoring; Evidence-Based Medicine; Female; Fibrinolytic Agents; Heparin; Heparin, Low-Molecular-Weight; Humans; Platelet Count; Pregnancy; Randomized Controlled Trials as Topic; Risk Assessment; Thrombocytopenia; Vitamin K

The antiphospholipid syndrome was individualized 12 years ago. Treatment was initially based on steroids, immunosuppressive drugs and intravenous immunoglobulin therapy. More recently, several retrospective studies have established that in most clinical conditions therapeutic doses of oral vitamin K antagonists (INR > or = 3) are sufficient to control the disease.. However, high dose immunoglobulin therapy is still indicated in a few cases, especially in life-threatening immune peripheral thrombocytopenia, and in recurrent foetal loss: in the latter indication, immunoglobulin therapy alone is efficient in 80% of cases.. Prospective studies are needed to assess the efficacy of intravenous immunoglobulin therapy in neurological complications occurring in spite of anticoagulant therapy, and in the context of repeated foetal losses when antithrombotic therapy with aspirin and subcutaneous heparin has failed.

Topics: Anticoagulants; Antiphospholipid Syndrome; Fibrinolytic Agents; Humans; Immunoglobulins, Intravenous; Patient Selection; Prospective Studies; Retrospective Studies; Thrombocytopenia; Thrombosis; Treatment Outcome; Vitamin K

Topics: Drug Hypersensitivity; Hemorrhage; Heparin; Heparin, Low-Molecular-Weight; Humans; Thrombocytopenia; Thrombosis; Vitamin K

Antithrombotic agents are widely prescribed in cardiovascular diseases. It is essential to understand the conditions of biological monitoring and the potential complications of these drugs. Treatment with unfractionated heparin and vitamin-K antagonists requires strict biological follow-up, the rules of which must be respected to avoid therapeutic failure or bleeding complications. Biological monitoring of low molecular weight heparins is extremely simple and that of antiplatelet agents is unnecessary. Regular patient follow-up, both clinical and biological, the respecting of contra-indications and recommendations of usage, and special attention to the problem of drug interaction, should result in better efficacy and tolerance of antithrombotic therapy.

Topics: Adult; Aged; Anticoagulants; Blood Coagulation Tests; Drug Administration Routes; Drug Administration Schedule; Drug Interactions; Drug Monitoring; Female; Hemorrhage; Heparin; Humans; Male; Middle Aged; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Pregnancy; Thrombocytopenia; Vitamin K

Topics: Administration, Oral; Adult; Animals; Anticoagulants; Coumarins; Drug Eruptions; Drug Hypersensitivity; Female; Fibrinolytic Agents; Hemorrhagic Disorders; Heparin; Humans; Male; Osteoporosis; Pregnancy; Pregnancy Complications, Cardiovascular; Risk Factors; Thrombocytopenia; Thrombolytic Therapy; Vitamin K

Topics: Anti-Bacterial Agents; Anticoagulants; Bacterial Infections; Drug Synergism; Hemorrhage; Hemorrhagic Disorders; Hemostasis; Humans; Platelet Adhesiveness; Platelet Aggregation; Prothrombin Time; Thrombocytopenia; Vitamin K

Topics: Acute Disease; Anticoagulants; Atrial Fibrillation; Cell Transformation, Neoplastic; Disseminated Intravascular Coagulation; Dose-Response Relationship, Drug; Embolization, Therapeutic; Female; Hemorrhage; Heparin; Humans; Mitral Valve; Postoperative Complications; Pregnancy; Pulmonary Embolism; Thrombocytopenia; Thromboembolism; Thrombophlebitis; Vitamin K; Warfarin

Topics: Blood Coagulation; Blood Coagulation Disorders; Blood Coagulation Factors; Blood Transfusion; Hemorrhage; Hemostasis; Heparin; Humans; Liver Diseases; Medical History Taking; Postoperative Complications; Preoperative Care; Surgical Procedures, Operative; Thrombocytopenia; Uremia; Vitamin K

Topics: Administration, Oral; Adult; Animals; Anticoagulants; Coumarins; Drug Eruptions; Drug Hypersensitivity; Female; Fibrinolytic Agents; Hemorrhagic Disorders; Heparin; Humans; Male; Osteoporosis; Pregnancy; Pregnancy Complications, Cardiovascular; Risk Factors; Thrombocytopenia; Thrombolytic Therapy; Vitamin K

Monitoring of vitamin K antagonist treatment with the international normalized ratio (INR) is obligatory, whereas this only applies to direct oral anticoagulants (DOAC) or low molecular weight heparin in the context of selected clinical scenarios. For DOAC the focus is on the determination of trough and peak plasma levels of the drug but for low molecular weight heparins the focus is on anti-Xa activity. The timing of blood sampling in relation to drug intake is essential for the interpretation of the results. A new-onset thrombocytopenia during hospitalization is common. The cause can frequently be identified based on the classification of the underlying disease, the day of onset and documentation of the dynamics of thrombocytopenia as well as the medication history. The importance of thrombophilia testing following a venous thromboembolism has decreased in the absence of clear therapeutic consequences; however, antiphospholipid antibody syndrome must not be overlooked as both the duration of treatment and the choice of anticoagulant depend on this.. Während bei einer Vitamin-K-Antagonisten-Therapie die Therapieüberwachung (International Normalized Ratio [INR]) obligat ist, gilt dies für direkte orale Antikoagulanzien (DOAK) oder niedermolekulares Heparin (NMH) nur in ausgewählten klinischen Szenarien. Bei DOAK steht die Bestimmung von Tal- und Spitzenspiegeln des Medikaments im Plasma im Vordergrund, bei NMH die Anti-Xa-Aktivität. Der Zeitpunkt der Probenabnahme in Relation zur Einnahme ist für die Bewertung essenziell. Eine neu aufgetretene Thrombozytopenie im Rahmen stationärer Behandlungen ist häufig. Einordnung der Grunderkrankung, Tag des Auftretens sowie Erfassung medikamentöser Einflüsse und ihrer Dynamik ermöglichen oft die Eingrenzung der Ursache. Die Thrombophilietestung nach venöser Thromboembolie wird aufgrund fehlender therapeutischer Konsequenz zunehmend seltener durchgeführt. Ein Antiphospholipidsyndrom darf aber nicht übersehen werden, da sowohl die Therapiedauer als auch die Wahl des Antikoagulans davon abhängen.

Topics: Anticoagulants; Heparin, Low-Molecular-Weight; Humans; Thrombocytopenia; Thrombophilia; Vitamin K

The impact of platelets on hematoma enlargement (HE) of intracerebral hemorrhage (ICH) is not yet sufficiently elucidated. Especially the role of reduced platelet counts on HE and clinical outcomes is still poorly understood. This study investigated the influence of thrombocytopenia on HE, functional outcome, and mortality in patients with ICH with or without prior antiplatelet therapy (APT).. Our study implies that thrombocytopenia does not affect rates of HE and functional outcome among ICH patients, neither in patients with nor without APT. In light of increased mortality, the significance of platelet transfusions for ICH patients with thrombocytopenia and previous APT should be explored in future studies.

Topics: Aged; Aged, 80 and over; Cerebral Hemorrhage; Cohort Studies; Female; Germany; Humans; Male; Platelet Aggregation Inhibitors; Platelet Count; Propensity Score; Retrospective Studies; Thrombocytopenia; Treatment Outcome; Vitamin K

Type 2 heparin-induced thrombocytopenia (HIT 2) is a rare pro-thrombotic disorder occurring in patients treated with heparin. It is defined as a clinical-biological syndrome associating the sudden onset of a thrombocytopenia, characterized by a drop of more than 50% of the initial platelet count, and thrombosis. We report two cases of HIT 2 occurring in patients with major bleeding tendency. The first HIT occurred in a patient whose management, in accordance with current guidelines, made it possible to control the thrombocytopenia and the anticoagulation despite the complexity of adapting and monitoring treatments in the context of recent cerebral hemorrhage. The second refers to an autoimmune HIT, which occurred in a patient whose management required the use of alternative therapies to the standard treatments suggested for HIT 2, to correct the severe refractory thrombocytopenia.

Topics: 4-Hydroxycoumarins; Aged; Anticoagulants; Arginine; Blood Coagulation Disorders; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Therapy, Combination; Hemorrhage; Heparin; Humans; Indenes; Intracranial Thrombosis; Male; Middle Aged; Neurosurgical Procedures; Pipecolic Acids; Sulfonamides; Thrombocytopenia; Vitamin K

Topics: Administration, Oral; Aged; Aged, 80 and over; Anticoagulants; Atrial Fibrillation; Female; Humans; Male; Middle Aged; Retrospective Studies; Thrombocytopenia; Vitamin K

Topics: Acute Kidney Injury; Aged; Anti-Inflammatory Agents; Antifibrinolytic Agents; Diagnosis, Differential; Disease Progression; Hematuria; Humans; Male; Methylprednisolone; Practice Guidelines as Topic; Thrombocytopenia; Vitamin K

Topics: Anticoagulants; Fibrinolytic Agents; Heparin; Humans; Thrombocytopenia; Thrombosis; Vitamin K; Warfarin

Previous trials investigating usage of four-factor prothrombin complex concentrate (4F-PCC) excluded patients with various thrombotic risk factors. The objective of this study was to evaluate the safety and effectiveness of 4F-PCC in a real-world setting based on an institutional protocol that does not have strict exclusion criteria.. This was a retrospective study of adult patients who received 4F-PCC. The primary outcome was a confirmed thromboembolism within 14 days after 4F-PCC administration. Secondary outcomes included international normalized ratio (INR) correction to <1.5 at first draw and incidence of INR rebound for patients undergoing reversal of warfarin and hemostatic effectiveness for patients experiencing a bleed.. Ninety-three patients received 4F-PCC. Sixty-three (67.7%) were reversed for bleeding and 30 (32.3%) for surgery. Eleven patients (11.8%) developed a thromboembolism within 14 days. The median (interquartile range) time to event was 5 (2-7) days. Significant risk factors were heparin-induced thrombocytopenia (P= .01) and major surgery within 14 days (P= .02), as well as the presence of >6 thrombotic risk factors (P= .01). For patients post-warfarin reversal, 45/63 (71.4%) achieved INR correction at first draw, 55/63 (87.3%) achieved INR correction within 24 hours, and 14/55 (25.5%) experienced INR rebound. Of these 14 patients, 8 (57.1%) did not receive concomitant vitamin K.. 4F-PCC was associated with a notable thromboembolic risk. All patient-specific risk factors should be considered prior to administration. 4F-PCC remains a useful agent for warfarin reversal. Lack of concomitant vitamin K may contribute to INR rebound.

Topics: Aged; Aged, 80 and over; Anticoagulants; Antifibrinolytic Agents; Blood Coagulation Factors; Cardiac Surgical Procedures; Dabigatran; Emergencies; Female; Gastrointestinal Hemorrhage; Heart Transplantation; Hemorrhage; Hemostatics; Heparin; Humans; Incidence; International Normalized Ratio; Intracranial Hemorrhages; Laparotomy; Male; Middle Aged; Preoperative Care; Pyrazoles; Pyridones; Retrospective Studies; Risk Factors; Rivaroxaban; Surgical Procedures, Operative; Thrombocytopenia; Thromboembolism; Vitamin K; Warfarin

Topics: Anticoagulants; Aspirin; Drug Therapy, Combination; Early Ambulation; Heparin, Low-Molecular-Weight; Humans; Pulmonary Embolism; Stockings, Compression; Thrombocytopenia; Venous Thrombosis; Vitamin K; Warfarin

Venous thromboembolism (VTE) is a common complication in patients with cancer. Because of their improved subcutaneous bioavailability and reliable antithrombotic efficiency low-molecular-weight heparins (LMWH) are preferably used for prevention and treatment of cancer-related VTE. Thromboprophylaxis with LMWH is well established in patients undergoing cancer surgery and hospitalized cancer patients, while outpatient prophylaxis remains contentious. LMWH are recommended over unfractionated heparins and vitamin K antagonists for initial treatment and secondary prophylaxis (3-6 months) after cancer-related VTE. Long-term secondary prophylaxis should be considered for patients with ongoing active malignancy and low bleeding risk. Due to absence of clinical studies in cancer patients, the use of novel oral anticoagulants is currently not recommended.

Topics: Fibrinolytic Agents; Heparin, Low-Molecular-Weight; Humans; International Normalized Ratio; Neoplasms; Postoperative Complications; Pulmonary Embolism; Randomized Controlled Trials as Topic; Risk Factors; Thrombocytopenia; Venous Thromboembolism; Vitamin K

Topics: Antithrombins; Aspirin; Blood Coagulation Disorders; Blood Platelet Disorders; Hemorrhagic Disorders; Humans; Receptors, Cytoplasmic and Nuclear; Thrombocytopenia; Vitamin K

Heparin-induced thrombocytopenia (HIT, type II) is an immune-mediated disorder due to antibodies formed against heparin-platelet factor 4 complexes, usually appearing at days 5 to 14 after initiation of heparin. It is important to recognize HIT because heparin prophylaxis or treatment paradoxically associates with new venous and/or arterial thrombosis. Early clinical suspicion and diagnosis together with proper pharmacotherapy and close laboratory monitoring are the cornerstones for successful management. This includes monitoring of Thrombocytopenia, its Timing to heparin administration, appearance of new Thrombosis or resistance to treatment, and differential diagnosis by exclusion of o Ther causes (the 4T's). Specific attention should be paid to the absence or presence of thrombosis and to tailoring thromboprophylaxis or anticoagulant therapy with a nonheparin alternative. Even in the absence of HIT-associated thrombosis, an active policy for prolonged thromboprophylaxis is demanded. Rapid and reliable assays should be developed for diagnosis and anticoagulation monitoring to secure safe management with nonheparins. Semiquantitative testing for on-call hours should be available and later confirmed as clinically needed. Alternative therapeutic options are available, but because their use is infrequent, experienced coagulation treatment centers should provide guidance in the treatment and in laboratory monitoring. Most of the evidence in HIT is grade IC, and thus the best evidence is provided by clinical experience. New anticoagulants and platelet inhibitors may offer future alternatives in the management of HIT, but the current treatment options provide the best experience and benefit. The joint clinical and laboratory guidelines provided in this article along with two practical case scenarios were prepared by a Nordic expert panel. They will be valuable for hematologists and colleagues who do not routinely encounter HIT.

Topics: Aged; Anticoagulants; Arginine; Cardiac Catheterization; Cardiac Surgical Procedures; Chondroitin Sulfates; Dermatan Sulfate; Female; Heparin; Heparin, Low-Molecular-Weight; Heparitin Sulfate; Hirudins; Humans; Male; Peptide Fragments; Pipecolic Acids; Recombinant Proteins; Sulfonamides; Thrombocytopenia; Vascular Surgical Procedures; Vitamin K; Young Adult

Topics: Anticoagulants; Hemorrhage; Humans; Thrombocytopenia; Thrombosis; Vitamin K; Wounds and Injuries

Anticoagulant therapy plays an important role in current medical practice. The main types of anticoagulant agents are: heparins, hirudins and vitamin K antagonists. None of the drugs used as anticoagulants meet the criteria of an ideal anticoagulant because they have side effects and they interact with other compounds. The main side effect of anticoagulant therapy is bleeding. The choice of a certain anticoagulant is made by the doctor based on the clinical context and also on the desired effect.

Topics: Anticoagulants; Azetidines; Benzylamines; Fondaparinux; Hemorrhage; Heparin; Hirudins; Humans; International Normalized Ratio; Polysaccharides; Thrombocytopenia; Vitamin K; Warfarin

Topics: Aged, 80 and over; Anticoagulants; Cardiac Surgical Procedures; Coumarins; Extremities; Gangrene; Heparin; Humans; International Normalized Ratio; Male; Middle Aged; Necrosis; Thrombocytopenia; Vitamin K; Warfarin

LMWHs are the major anticoagulant/antithrombotic treatment given to pregnant women to prevent and treat venous thromboembolism despite the absence of specific clinical trials. An emerging indication, the prevention of adverse pregnancy outcomes, is under investigation. During pregnancy, LMWHs seem to be safe and efficient. Some uncertainties remain about the management of rare potential side effects, particularly in the event of heparin intolerance and with cross-reactivity to danaparoid sodium.

Topics: Abnormalities, Drug-Induced; Anticoagulants; Contraindications; Dermatitis, Allergic Contact; Female; Fibrinolytic Agents; Hemorrhage; Heparin; Humans; Pregnancy; Pregnancy Complications, Hematologic; Thrombocytopenia; Thrombophilia; Venous Thrombosis; Vitamin K

According to their code of professional conduct, German physicians are obliged to report suspected cases of adverse drug reactions (ADRs) to the Drug Commission of the German Medical Association (AkdA). On the basis of an agreement between the German Medical Association and the Federal Institute for Drugs and Medical Devices (BfArM) a common pharmacovigilance database within the German spontaneous reporting system was created. A user-friendly application program developed in-house enables the user to conduct searches about reported ADRs covering a wide variety of questions within a short period of time. ADRs caused by anticoagulants and by antiplatelet drugs still belong to the most reported adverse events. The most frequently reported suspected drugs are heparins, followed by ticlopidine, phenprocoumon, acetylsalicylic acid, and clopidogrel. Bleeding complications are the most often described ADR symptoms of any anticoagulation therapy, especially of phenprocoumon and acetylsalicylic acid. Another serious ADR is heparin-induced thrombocytopenia or changes in blood counts (CBC) due to ticlopidine and clopidogrel. During the past few years a reduction in severe reactions, such as cerebral hemorrhage, especially with fatal outcome was detectable because of better clinical management of oral anticoagulant therapy and of adverse events concerning heparin.

Topics: Administration, Oral; Adverse Drug Reaction Reporting Systems; Anticoagulants; Aspirin; Association; Blood Cell Count; Cerebral Hemorrhage; Clopidogrel; Databases, Factual; Drug Information Services; Germany; Hemorrhage; Heparin; Humans; Phenprocoumon; Platelet Aggregation Inhibitors; Product Surveillance, Postmarketing; Thrombocytopenia; Ticlopidine; Time Factors; Treatment Outcome; Vitamin K

Antivitamin K treatments (AVK) are related to increased morbidity and mortality, notably in elderly patients. The International Normalized Ratio (INR) should be well controlled and its stabilisation within the therapeutic range help to prevent the haemorrhagic complications.. A one-year prospective survey on all the cases of excess AVK was conducted in hospitalised patients aged over 70.. During the study period, 225 hospitalised patients treated with AVK (mean age 84 years) were identified: 62% received warfarin, 19% fluindione, 8% acenocoumarol and 11% received several successive AVK. During this period, 1.904 INR measurements were recorded: 97 (5.1%) were > or =5.0 and 12 (0.63%) were > or =9.0. In all, 59 patients (23.1%) exhibited one or several episodes of excess AVK (INR > or =5.0) and 57 exhibited a target INR of 2.5. Three patients died of accidental haemorrhage--two of them due to intra-cerebral bleeding--among the 59 patients with excess AVK. In three cases, the INR was greater than 7.0 at the time of the accident.. In half of the cases of excess, the episode occurred during the month following initiation of treatment with AVK. In nearly two thirds of cases, a change had been made in drug therapy in the 10 days preceding the excess, with the prescription of a drug enhancing the effect of the AVK: anti-infection agents (antibiotics and anti-fungals) and amiodarone were the drugs most frequently involved. Oral or intravenous vitamin K1 was administered in only 19% of cases.. In very old patients treated with oral anticoagulants, certain risk factors must be identified: the initiation period of treatment, the occurrence of an intercurrent disease and the subsequent change in the drug therapy. INR monitoring should be intensified in order to detect any excess and, if detected, ensure the optimal management of the patient.

Topics: 4-Hydroxycoumarins; Aged; Aged, 80 and over; Amiodarone; Anti-Arrhythmia Agents; Anti-Bacterial Agents; Anticoagulants; Antifungal Agents; Coma; Drug Administration Schedule; Drug Overdose; Drug Synergism; Female; Hematoma, Subdural; Hemorrhage; Hospitalization; Humans; Indenes; International Normalized Ratio; Male; Prospective Studies; Pulmonary Embolism; Thrombocytopenia; Vitamin K; Warfarin

Topics: Anticoagulants; Contraindications; Creatinine; Drug Interactions; Hemorrhage; Heparin, Low-Molecular-Weight; Humans; Platelet Count; Renal Insufficiency; Thrombocytopenia; Venous Thrombosis; Vitamin K

Topics: 4-Hydroxycoumarins; Anticoagulants; Hemorrhage; Heparin; Humans; Indenes; Morbidity; Thrombocytopenia; Thrombosis; Vitamin K

The purpose of our study was to clarify the frequency of these causes.. Retrospective study using reports of newborns in the neonatal unit in Sousse (Tunisia) from 1991 to 1996, hospitalized for hemorrhagic syndrome defined by bleeding, exteriorized or not, whatever its importance, severity, causes and the associated clinical and biological disorders. Isolated meningeal hemorrhages, limited cutaneo-mucous hemorrhages (conjunctival hemorrhages, bruises), and genital crises of the newborn, were excluded.. One hundred and fifty-five hemorrhagic syndromes were observed from 7,128 newborn infants (2.17% of hospitalization). Sex ratio was 1.42. Prematurity rate was 35.7%. The Apgar score was < 7 at one minute in 40.7% of cases. Disorders associated with hemorrhagic syndromes were observed in 118 newborn infants (76.1%) with a predominance of neonatal infections (35.6%). The etiology of neonatal hemorrhages was specified in 93% of cases: newborn hemorrhagic disease (27.7%), disseminated intravascular coagulation (27.1%), isolated thrombocytopenia (9%), digestive lesions (13.5%), and obstetrical trauma (2.6%).. The frequency of the newborns hemorrhagic syndromes underlines the need for its systematic prevention by vitamin K in the antenatal period to the mother and after birth to the newborn.

Topics: Disseminated Intravascular Coagulation; Humans; Incidence; Infant, Newborn; Retrospective Studies; Thrombocytopenia; Vitamin K; Vitamin K Deficiency Bleeding

Four classes of anticoagulants are now available: vitamin K antagonists, heparin, Orgaran and hirudin. For each of these classes the mechanism of the anticoagulant effect, the usual doses and biological monitoring are described. Each low molecular weight heparin must be considered as an original product. Orgaran and hirudin are new antithrombotic agents allowing to solve the dramatic problems raised by heparin-induced thrombocytopenia.

Topics: Anticoagulants; Chondroitin Sulfates; Dermatan Sulfate; Heparin; Heparitin Sulfate; Hirudin Therapy; Humans; Thrombocytopenia; Vitamin K

Topics: Algorithms; Antithrombin III; Biopsy; Blood Coagulation Disorders; Disseminated Intravascular Coagulation; Gastrointestinal Hemorrhage; Humans; Hypersplenism; Hypertension, Portal; Liver; Liver Diseases; Liver Transplantation; Thrombocytopenia; Vitamin K

Topics: Airway Obstruction; Hematoma; Humans; Macroglossia; Male; Middle Aged; Platelet Count; Thrombocytopenia; Tongue; Vitamin K

Topics: 4-Hydroxycoumarins; Anticoagulants; Hemorrhage; Heparin, Low-Molecular-Weight; Humans; Hypertension, Pulmonary; Indenes; Myocardial Infarction; Risk Factors; Thrombocytopenia; Thrombophlebitis; Vitamin K

A case of mitral and aortic valvular replacement combined with double coronary artery bypass grafting is reported in a 64-year-old woman who presented with a history of heparin-induced thrombocytopenia. The use of a conventional dose of heparin did not induce the formation of a plasma platelet-aggregation factor. The necessity of postoperative anticoagulation was ensured by the prescription of antivitamin K, started on the morning of the operative day.

Topics: Blood Coagulation Factors; Cardiac Surgical Procedures; Extracorporeal Circulation; Female; Heparin; Humans; Middle Aged; Platelet Activating Factor; Platelet Aggregation; Postoperative Period; Thrombocytopenia; Vitamin K

A rare but important side effect of antibiotics is their inhibitory effect on haemostasis and blood coagulation. Modern antibiotics with a wide spectrum like cephalosporins of the 2nd and 3rd generation, as well as semisynthetic penicillins, can imitate warfarin in its effect on the blood clotting system. Other antibiotics can enhance the effect of warfarin derivatives when given simultaneously. The mechanism by which penicillin and its derivatives inhibit platelet aggregation is not yet clear. Other antibiotics can induce thrombo-cytopenia. Before antibiotic treatment is started the doctor should consider liver and kidney function, a possible malnutrition, interaction with other drugs (especially inhibitors of platelet aggregation and warfarin derivatives), and other diseases of the patient that also prolong bleeding time.

Topics: Anti-Bacterial Agents; Bacterial Infections; Blood Coagulation Factors; Blood Coagulation Tests; Hemorrhage; Humans; Otorhinolaryngologic Diseases; Platelet Aggregation; Thrombocytopenia; Vitamin K

Topics: Animals; Anticoagulants; Blood Coagulation; Blood Coagulation Factors; Drug Interactions; Drug-Related Side Effects and Adverse Reactions; Fibrinolysis; Hemorrhage; Hemostasis; Heparin; Humans; Snake Venoms; Thrombocytopenia; Vitamin K; Warfarin

Thrombocytopenia associated with moxalactam disodium administration occurred in an elderly, debilitated, 84-year-old male. The patient presented with a decreased platelet count and prolongation of prothrombin time and partial thromboplastin time. Occult blood was found in the urine and stool, and generalized petechiae with ecchymoses were found over the entire body. The moxalactam was discontinued because of suspected drug-induced thrombocytopenia, and daily vitamin K therapy was instituted. By day 2 of vitamin K therapy, the platelet count had risen slightly, but the patient's condition did not improve. On day 3 of vitamin K therapy, the platelet count had decreased. There was a generalized worsening of the patient's medical condition, and he expired two days later. The use of moxalactam has been associated with thrombocytopenia. The possibility of hemorrhage consequent to the use of this antibiotic is clinically important.

Topics: Aged; Humans; Male; Moxalactam; Partial Thromboplastin Time; Platelet Count; Prothrombin Time; Thrombocytopenia; Vitamin K

Laboratory control of anticoagulant treatments is still unclear, in spite of 25 years experience, better knowledge of the mechanisms of action of the different drugs, and the new techniques available. In general, laboratory control includes a test specific for the action of the drug involved, associated or not with a test that reflects global coagulability. During heparin treatment, the association of recalcification time or activated partial thromboplastin time with heparin levels is recommended. A weekly platelet count can eliminate heparin-induced thrombocytopenia. During oral anticoagulant treatment, the association of thromboplastin time or Owren's thrombotest with activated partial thromboplastin time is indicated. The therapeutic ranges for thromboplastin times are different according to the reagents used and should be specified by the laboratory since present methods of standardization are not yet satisfactory.

Topics: Anticoagulants; Blood Coagulation Tests; Heparin; Humans; Partial Thromboplastin Time; Platelet Count; Thrombocytopenia; Thromboembolism; Vitamin K

Disorders of coagulation are part of the clinical syndrome in hepatic failure. The pathophysiology of these disorders is discussed; analysis of coagulation defects in hepatic disorders does not help in differential diagnosis of hepatic diseases in the proper sense, but it is of considerable prognostic value. Therapy of hepatic diseases is discussed taking into account the pathophysiology of hepatic disorders; success of any therapeutic approach however is very limited, because of the bad prognosis of the underlying disease.

Topics: Antifibrinolytic Agents; Blood Coagulation Factors; Blood Platelets; Blood Transfusion; Fibrinolysis; Hemorrhagic Disorders; Heparin; Humans; Liver; Liver Diseases; Prognosis; Splenectomy; Thrombocytopenia; Vitamin K

Topics: Blood Cell Count; Blood Platelets; Hemorrhage; Humans; Infant, Newborn; Thrombocytopenia; Time Factors; Vitamin K; Vitamin K Deficiency Bleeding

Topics: Asphyxia Neonatorum; Autoantibodies; Blood Coagulation Tests; Blood Platelets; Blood Transfusion; Capillary Fragility; Capillary Permeability; Cerebral Hemorrhage; Disseminated Intravascular Coagulation; Exchange Transfusion, Whole Blood; Female; Hemophilia A; Hemorrhage; Hemorrhagic Disorders; Heparin; Humans; Infant, Newborn; Infant, Newborn, Diseases; Lung; Maternal-Fetal Exchange; Pregnancy; Thrombocytopenia; Vitamin K; Vitamin K Deficiency; von Willebrand Diseases

Topics: Adult; Blood Coagulation Tests; Blood Group Incompatibility; Exchange Transfusion, Whole Blood; Female; Histocompatibility; Histocompatibility Antigens; Humans; Immunity, Cellular; Infant, Newborn; Infant, Newborn, Diseases; Male; Maternal-Fetal Exchange; Pedigree; Pregnancy; Thrombocytopenia; Vitamin K; Vitamin K Deficiency

Topics: Animals; Ascorbic Acid; Ascorbic Acid Deficiency; Blood Coagulation Factors; Blood Platelet Disorders; Blood Platelets; Dicumarol; Factor VII; Glycine max; Hemorrhage; Hemostatics; Humans; Pedigree; Phospholipids; Plasma; Prothrombin; Prothrombin Time; Rabbits; Thrombocytopenia; Thromboplastin; Vitamin K; Vitamin K Deficiency

Topics: Anemia, Hemolytic, Congenital; Anemia, Neonatal; Blood Coagulation Factors; Blood Transfusion; Chlorothiazide; Dicumarol; Female; Glucosephosphate Dehydrogenase Deficiency; Hemoglobinopathies; Hemophilia A; Hemorrhage; Humans; Infant, Newborn; Iron; Liver; Pregnancy; Thrombocytopenia; Vitamin K; Vitamin K Deficiency Bleeding

Topics: Anti-Bacterial Agents; Blood Cell Count; Blood Coagulation; Blood Coagulation Disorders; Blood Coagulation Tests; Blood Platelets; Child; Cystic Fibrosis; Fibrinolysis; Gastrointestinal Hemorrhage; Hemoptysis; Hepatomegaly; Humans; Liver; Liver Function Tests; Lung; Prospective Studies; Prothrombin Time; Splenomegaly; Thrombocytopenia; Thromboplastin; Vitamin K

Topics: Aging; Anticoagulants; Blood Coagulation Disorders; Blood Coagulation Factors; Blood Platelet Disorders; Blood Platelets; Blood Preservation; Blood Specimen Collection; Blood Transfusion; Exchange Transfusion, Whole Blood; Humans; Isoantibodies; Plasmapheresis; Thrombocythemia, Essential; Thrombocytopenia; Vitamin K

Topics: Blood Coagulation Disorders; Child; Glucocorticoids; Hemorrhagic Disorders; Humans; Thrombocytopenia; Vitamin K

Topics: Blood Coagulation Disorders; Child, Preschool; Female; Humans; Rocky Mountain Spotted Fever; Thrombocytopenia; Vitamin K; Vitamin K Deficiency

Topics: Arrhythmias, Cardiac; Clinical Laboratory Techniques; Digoxin; Female; Goiter; Graves Disease; Hepatomegaly; Humans; Hyperthyroidism; Hypoprothrombinemias; Infant; Infant, Newborn; Infant, Newborn, Diseases; Iodides; Liver Diseases; Maternal-Fetal Exchange; Prednisolone; Pregnancy; Pregnancy Complications; Reserpine; Splenomegaly; Thrombocytopenia; Toxicology; Vitamin K

Topics: Ascorbic Acid; Dental Caries; Geriatrics; Gingival Diseases; Hemostatics; Humans; Periodontal Diseases; Radiography, Dental; Surgery, Oral; Thrombocytopenia; Tooth Extraction; Vitamin K

Topics: Anemia; Anemia, Macrocytic; Anemia, Megaloblastic; Blood Platelet Disorders; Factor VII Deficiency; Female; Humans; Hypoprothrombinemias; Pregnancy; Pregnancy Complications; Pregnancy Complications, Hematologic; Thrombocytopenia; Vitamin K