Estimated incidence of acute pulmonary embolism in a Korean hospital.
Clin Appl Thromb Hemost. 2011 Jun;17(3):297-301
Authors: Choi WI, Lee MY, Oh D, Rho BH, Hales CA
Abstract
Patients with acute pulmonary embo…

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Economic and practical aspects of thromboprophylaxis with unfractionated and low-molecular-weight heparins in hospitalized medical patients.

Clin Appl Thromb Hemost. 2009 Oct;15(5):489-500

Authors: Pineo GF, Hull RD

Acutely ill medical patients are at significant risk of developing venous thromboembolic (VTE) complications during or after their hospitalization. Venous thromboembolic events, such as proximal deep vein thrombosis (DVT) or pulmonary embolism (PE), place a high and unacceptable burden on health care resources, up to US$1.5 billion annually in the United States. However, the burden of VTE can be reduced by use of appropriate thromboprophylaxis. Prophylaxis of VTE with either a low-dose unfractionated heparin (UFH) or a low-molecular-weight heparin (LMWH) in medical inpatients is effective, well tolerated and cost-effective, compared with no prophylaxis. Low-molecular-weight heparins have a number of practical benefits over UFH, including once-daily subcutaneous injection and the potential to be used in the outpatient setting. These clinical advantages could translate to improved patient adherence to therapy and provide economic benefits, where LMWHs are more cost-effective compared with UFH.

PMID: 19520676 [PubMed - indexed for MEDLINE]

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D-dimers, thrombin-antithrombin complexes, and risk factors for thromboembolism in hospitalized patient.

Clin Appl Thromb Hemost. 2009 Dec;15(6):666-75

Authors: Pottier P, Fouassier M, Hardouin JB, Volteau C, Planchon B

INTRODUCTION: There is lack of data about the correlation between hemostatic markers and the clinical and biological risk factors (RFs) for venous thromboembolism (VTE) in medical inpatients without suspicion of acute VTE. MATERIAL AND METHODS: To evaluate the coagulation activation status in patients with current known RFs for VTE, the authors measured 2 markers of hypercoagulability, thrombin antithrombin (TAT) complexes and D-dimers, at day 1 in 165 patients hospitalized in internal medicine wards without suspected acute VTE. All known RFs for VTE were systematically assessed at admission and classified in a chronological way as permanent or transient. RESULTS: Surprisingly, TAT values followed a multimodal distribution. D-dimers showed a normal distribution after a logarithmic transformation (P = .34, Shapiro-Wilk test). Interestingly, a significant progression in D-dimer levels was found according to the chronological classification of RFs. D-dimer variations on multivariate analysis (not applicable for TAT because of the multimodal distribution) correlated independently with a recent inability to walk and an increase in C reactive protein level more than 10 mg/L. CONCLUSIONS: (a) this study is the first to describe the variations of hypercoagulability markers according to a systematic screening of RFs for VTE in inpatients without suspicion of acute VTE, (b) TAT appeared as a less relevant marker of hypercoagulability than D-dimers in internal medicine inpatients, (d) the chronological classification of RFs identified clearly groups at risk for the prethrombotic state, and (d) an increased hypercoagulability state was demonstrated in patients with an association between a recent immobility and increased inflammatory markers.

PMID: 18796458 [PubMed - indexed for MEDLINE]

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Lessons from ximelagatran: issues for future studies evaluating new oral direct thrombin inhibitors for venous thromboembolism prophylaxis in orthopedic surgery.

Clin Appl Thromb Hemost. 2009 May-Jun;15(3):316-26

Authors: Lazo-Langner A, Rodger MA, Wells PS

Venous thromboembolism is a frequent complication of total hip and knee replacement requiring prophylaxis with anticoagulants. A direct thrombin inhibitor-ximelagatran-did not show advantages over other anticoagulants and it was withdrawn from the market; however, new drugs are being developed. We conducted a systematic review and meta-analysis to identify conditions under which ximelagatran might potentially be superior to current standards. Medline, EMBASE, the Cochrane Library, and grey literature were screened for randomized trials comparing ximelagatran with warfarin or low-molecular-weight heparin for thromboprophylaxis in total hip or knee replacement. Two reviewers independently assessed and extracted data. A meta-analysis with especial attention to statistical heterogeneity was conducted. This study suggested that the risk-benefit profile of ximelagatran-and probably other similar agents-depends on the type of surgery, the initial timing of administration, and probably the dose. These issues should be explicitly explored in future trials evaluating new direct thrombin inhibitors.

PMID: 19028773 [PubMed - indexed for MEDLINE]

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Are all low molecular weight heparins equivalent in the management of venous thromboembolism?

Clin Appl Thromb Hemost. 2008 Oct;14(4):385-92

Authors: Fareed J, Jeske W, Fareed D, Clark M, Wahi R, Adiguzel C, Hoppensteadt D

Low molecular weight heparins are replacing unfractionated heparin in a number of clinical indications because of their improved subcutaneous bioavailability and more predictable antithrombotic response. Clinical trials have demonstrated that low molecular weight heparins are at least as safe and effective as unfractionated heparin for the initial treatment of venous thromboembolism, and unfractionated heparin and warfarin for primary and secondary thromboprophylaxis. The mechanism behind the antithrombotic action of low molecular weight heparins is not fully understood but is likely to involve inhibition of coagulation factors Xa and IIa (thrombin), release of tissue-factor-pathway inhibitor, and inhibition of thrombin activatable fibrinolytic inhibitor. Different low molecular weight heparins have been shown to have various effects on coagulation parameters. Seven low molecular weight heparins are currently marketed worldwide, each demonstrated distinct chemical entities with unique pharmacokinetic and pharmacodynamic profiles. Each low molecular weight heparin is approved for specific indications based on the available efficacy and safety data for that product. The relative efficacy and safety of the low molecular weight heparins are unclear because there have been very few direct comparisons in randomized clinical trials. While recommending low molecular weight heparins for the prevention and treatment of venous thromboembolism, clinical guidelines have not specified individual agents. National and international organizations recognize that low molecular weight heparins are distinct entities and that they should not be used interchangeably in clinical practice. Each low molecular weight heparin should be used at the recommended dose when efficacy and safety data exist for the condition being treated. When these data are not available, the dosing and administration of low molecular weight heparins must be adapted from existing data and recommendations.

PMID: 18815137 [PubMed - indexed for MEDLINE]

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Central Venous Catheterization: A Prospective, Randomized, Double-Blind Study.

Clin Appl Thromb Hemost. 2008 Jul 1;

Authors: Mer M, Duse AG, Galpin JS, Richards GA

Central venous catheters (CVCs) are extensively used worldwide. Mechanical, infectious and thrombotic complications are well described with their use and may be associated with prolonged hospitalization, increased medical costs and mortality. CVCs account for an estimated 90% of all catheter-related bloodstream infections (CRBSI) and a host of risk factors for CVC-related infections have been documented. The duration of use of CVCs remains controversial and the length of time such devices can safely be left in place has not been fully and objectively addressed in the critically ill patient. Antimicrobial-impregnated catheters have been introduced in an attempt to limit catheter-related infection (CRI) and increase the time that CVCs can safely be left in situ. Recent meta-analyses concluded that antimicrobial-impregnated CVCs appear to be effective in reducing CRI. The authors conducted a prospective, randomized, double-blind study at Johannesburg Hospital over a 4year period. The study entailed a comparison of standard triple-lumen versus antimicrobial impregnated CVCs on the rate of CRI. Our aim was to determine whether we could safely increase the duration of catheter insertion time from our standard practice of seven days to 14 days, to assess the influence of the antimicrobial impregnated catheter on the incidence of CRI, and to elucidate the epidemiology and risks of CRI. One hundred and eighteen critically ill patients were included in the study which spanned 34 951.5 catheter hours (3.99 catheter years). It was found that antimicrobial catheters did not provide any significant benefit over standard catheters, which the authors feel can safely be left in place for up to14 days with appropriate infection control measures. The most common source of CRI was the skin. The administration of parenteral nutrition and the site of catheter insertion (internal jugular vein vs subclavian vein) were not noted to be risk factors for CRI. There was no clinical evidence of thrombotic complication in either of the study groups. This study offers direction for the use of CVCs in critically ill patients and addresses many of the controversies that exist.

PMID: 18593746 [PubMed - as supplied by publisher]

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