Guyatt GH, Eikelboom JW, Gould MK, et al. Approach to outcome measurement in the prevention of thrombosis in surgical and medical patients: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada.
Chest (Impact Factor: 7.48). 02/2012; 141(2 Suppl):e185S-94S. DOI: 10.1378/chest.11-2289
Source: PubMed


This article provides the rationale for the approach to making recommendations primarily used in four articles of the Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines: orthopedic surgery, nonorthopedic surgery, nonsurgical patients, and stroke. Some of the early clinical trials of antithrombotic prophylaxis with a placebo or no treatment group used symptomatic VTE and fatal PE to measure efficacy of the treatment. These trials suggest a benefit of thromboprophylaxis in reducing fatal PE. In contrast, most of the recent clinical trials comparing the efficacy of alternative anticoagulants used a surrogate outcome, asymptomatic DVT detected at mandatory venography. This outcome is fundamentally unsatisfactory because it does not allow a trade-off with serious bleeding; that trade-off requires knowledge of the number of symptomatic events that thromboprophylaxis prevents. In this article, we review the merits and limitations of four approaches to estimating reduction in symptomatic thrombosis: (1) direct measurement of symptomatic thrombosis, (2) use of asymptomatic events for relative risks and symptomatic events from randomized controlled trials for baseline risk, (3) use of baseline risk estimates from studies that did not perform surveillance and relative effect from asymptomatic events in randomized controlled trials, and (4) use of available data to estimate the proportion of asymptomatic events that will become symptomatic. All approaches have their limitations. The optimal choice of approach depends on the nature of the evidence available.

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    • "In patients who received inadequate prophylaxis, we differentiate two groups: excessive inadequate prophylaxis, when the patient received pharmacological ATP without clinical indication, or when the administered dose was higher than recommended. On the other side, insufficient inadequate prophylaxis when the patient had an increased VTE risk but received no prescription for prophylaxis or the prescribed dose was less than recommended [9,16]. "
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    ABSTRACT: BACKGROUND: Venous thromboembolic disease (VTE) is associated with high morbi-mortality. Adherence rate to the recommendations of antithrombotic prophylaxis guidelines (ATPG) is suboptimal. The aim of this study was to describe the adequacy of antithrombotic prophylaxis (ATP) in hospitalized patients as the initial stage of a program designed to improve physician adherence to -ATP recommendations in Argentina. METHODS: This study was a multicenter, cross-sectional study that included 28 Institutions throughout 5 provinces in Argentina. RESULTS: 1315 patients were included, 729 (55.4%) were hospitalized for medical (clinical) reasons, and 586 (44.6%) for surgical reasons. Adequate ATP was provided to 66.9% of the patients and was more frequent in surgical (71%) compared to clinical (63.6%) subjects (p < 0.001). Inadequate ATP resulted from underuse in 76.6% of the patients. Among clinical, 203 (16%) had increased bleeding risk and mechanical ATP was used infrequently. CONCLUSIONS: The adequacy of ATP was better in low VTE risk clinical and surgical patients and high VTE risk in orthopedic patients. There was worse adequacy in high risk patients (with active neoplasm) and in those with pharmacological ATP contraindications, in which the use of mechanical methods was scarce. The adequacy of ATP was greater at institutions with < 150 beds compared with larger institutions. This is the first multicentric study reporting ATP in Argentina. Understanding local characteristics of medical performance within our territory is the first step in order to develop measures for improving ATP in our environment.
    Full-text · Article · Jul 2014 · Thrombosis Journal
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    • "Ogata [19], on the other hand found that D-dimer and high NIHSS were associated with a high risk of DVT/PE in patients with intracranial hemorrhage. Much of the differences between studies may be due to small patient populations and differences in the means of assessment of DVT/PE [4]. "
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    ABSTRACT: Objective: Deep venous thrombosis (DVT) and pulmonary embolus (PE) are serious problems for patients admitted to the hospital with stroke, subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH) and transient ischemic attack (TIA). The purpose of this paper is to further understand the factors that place certain patients at increased risk of DVT/PE. Methods: At a 600 bed hospital, a retrospective analysis of data from 2613 patients admitted with a diagnosis of stroke, SAH, ICH or TIA in the time range 1/2008 through 3/2012 was carried out. The data was taken from the hospital’s Get with the Guidelines database and included 28 variables. These included initial NIH stroke scale, length of stay, heart failure, ambulatory by day 2 after admission, altered mental status,and renal failure among others. Multiple analyses were carried out to determine whether there were univariable or multivariable effects of any of the factors on the risk for DVT/PE. Results: The risk of DVT/PE was highest in patients with SAH and ICH and smallest with TIA. Multivariable analyses were performed and revealed only altered level of consciousness or heart failure as significant risks for DVT/PE. With the limited available data, administration of subcutaneous heparin or other chemoprophylaxis did not reduce the risk of DVT/PE. Conclusion: Although many of the variables used to describe the stroke patient are correlated, in multivariable analyses only heart failure and altered level of consciousness were important risk factors for DVT/PE. The risk of DVT/PE was 7 fold greater in patients in patients with both of these risk factors.
    Full-text · Article · Apr 2014 · The Open Neurology Journal
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    • "An example of the rigorous application of GRADETable 2 presents a summary of finding table from AT9 that surprised some in the thrombosis community, at least in part because it contrasted with the recommendation in the previous iteration of the guidelines [18] . The associated recommendation in AT9 acknowledges aspirin as a possible approach to VTE prophylaxis in major orthopedic surgery [19]. "
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    ABSTRACT: More than 70 organizations worldwide have adopted the GRADE methodology for guideline development. The ninth iteration of the American Collage of Chest Physicians guidelines (AT9) adopted structural and policy changes that resulted in a greater adherence to GRADE guidance than previous iterations. The most important of these changes include minimizing the impact of financial and intellectual COI; increasing the rigor of evidence evaluation; acknowledging uncertainty in estimates of typical values and preferences; and awareness of the large variability in values and preferences. One of the consequences of the greater adherence to GRADE methodology is an increase in weak versus strong recommendations in AT9. The result of the GRADE process highlights the desirability of higher quality evidence both regarding the outcomes of alternative management strategies, and of the distribution of values and preferences in patients considering those alternatives. It also encourages shared decision making in encounters between physicians and patients. Although some physicians might find the uncertainty underlying medical practice discouraging or unsettling, relative to denying or obscuring the uncertainty, acknowledging and addressing the uncertainty will lead to more credible, realistic and useful recommendations. This article is protected by copyright. All rights reserved.
    Full-text · Article · Jun 2013 · Journal of Thrombosis and Haemostasis
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