1,721,296 research outputs found
Systematic review and meta-analysis of the clinical effectiveness of point-of-care testing for anticoagulation management during ECMO
No full textStudy objective: Viscoelastic point-of-care (POC) tests are commonly used to provide prompt diagnosis of coagulopathy and allow targeted treatments in bleeding patients on ECMO. We evaluated the clinical effectiveness of point-of-care (POC) testing for anticoagulation management in patients on extracorporeal membrane oxygenation (ECMO). Design: Systematic review and meta-analysis. Eligible studies evaluating the use of thromboelastography- or thromboelastometry-guided algorithms, anti-factor Xa and platelet function testing were selected after screening the literature from July 1975 to January 2020. Setting: Patients on ECMO support. Patients: Anticoagulation management on ECMO patients. Interventions: Rotational thromboelastometry, thromboelastography, alone or combined with platelet function testing. Trials monitoring the anticoagulation effects during ECMO using an anti-factor Xa assay were included in the systematic review. Measurements: The primary outcomes were bleeding events, surgical revisions, thrombosis events and ECMO circuit change/failure. Secondary outcomes were blood-product transfusions, cerebrovascular accidents, mortality on ECMO, ECMO duration, intensive care unit and hospital discharge rates, and in-hospital mortality. Main results: Thirty-one trials enrolling 1684 participants were included in the systematic review. Four trials enrolling 547 subjects were included in the meta-analysis. The use of a POC testing device resulted in improved detection of surgical bleeding (RR: 0.68, 95% CI 0.49 to 0.94, I2 = 0%; χ2 test for heterogeneity, P = 0.02). The use of POC-guided algorithms did not affect bleeding (RR:0.78, 95% CI 0.58 to 1.04, I2 = 47%; χ2 test for heterogeneity, P = 0.09), thrombosis events (RR:1.35, 95% CI 0.86 to 2.12, I2 = 37%; χ2 test for heterogeneity, P = 0.19), or ECMO circuit/change (RR:0.90, 95% CI 0.48 to 1.71, I2 = 28%; χ2 test for heterogeneity, P = 0.75). Conclusion: Routine use of POC tests did not improve the main clinical outcomes beyond suggesting a diagnosis of surgical bleeding in ECMO patients
From Principle to Practice: Bridging the Gap in Patient Profiling
Full text linkThe standard clinical coagulation assays, activated partial thromboplastin time (aPTT) and prothrombin time (PT) cannot predict thrombotic or bleeding risk. Since thrombin generation is central to haemorrhage control and when unregulated, is the likely cause of thrombosis, thrombin generation assays (TGA) have gained acceptance as “global assays” of haemostasis. These assays generate an enormous amount of data including four key thrombin parameters (lag time, maximum rate, peak and total thrombin) that may change to varying degrees over time in longitudinal studies. Currently, each thrombin parameter is averaged and presented individually in a table, bar graph or box plot; no method exists to visualize comprehensive thrombin generation data over time. To address this need, we have created a method that visualizes all four thrombin parameters simultaneously and can be animated to evaluate how thrombin generation changes over time. This method uses all thrombin parameters to intrinsically rank individuals based on their haemostatic status. The thrombin generation parameters can be derived empirically using TGA or simulated using computational models (CM). To establish the utility and diverse applicability of our method we demonstrate how warfarin therapy (CM), factor VIII prophylaxis for haemophilia A (CM), and pregnancy (TGA) affects thrombin generation over time. The method is especially suited to evaluate an individual's thrombotic and bleeding risk during “normal” processes (e.g pregnancy or aging) or during therapeutic challenges to the haemostatic system. Ultimately, our method is designed to visualize individualized patient profiles which are becoming evermore important as personalized medicine strategies become routine clinical practice
Low-molecular-weight heparin venous thromboprophylaxis in critically ill patients with renal dysfunction: A subgroup analysis of the PROTECT trial
Full text linkINTRODUCTION: There is concern about excessive bleeding when low-molecular-weight heparins (LMWHs) are used for venous thromboembolism (VTE) prophylaxis in renal dysfunction. Our objective was to evaluate whether LMWH VTE prophylaxis was safe and effective in critically ill patients with renal dysfunction by conducting a subgroup analysis of PROTECT, a randomized blinded trial. METHODS: We studied intensive care unit (ICU) patients with pre-ICU dialysis-dependent end-stage renal disease (ESRD; pre-specified subgroup; n = 118), or severe renal dysfunction at ICU admission (defined as ESRD or non-dialysis dependent with creatinine clearance [CrCl] <30 ml/min; post hoc subgroup; n = 590). We compared dalteparin, 5000 IU daily, with unfractionated heparin (UFH), 5000 IU twice daily, and considered outcomes of proximal leg deep vein thrombosis (DVT); pulmonary embolism (PE); any VTE; and major bleeding. Adjusted hazard ratios [HR] were calculated using Cox regression. RESULTS: In patients with ESRD, there was no significant difference in DVT (8.3% vs. 5.2%, p = 0.76), any VTE (10.0% vs. 6.9%; p = 0.39) or major bleeding (5.0% vs. 8.6%; p = 0.32) between UFH and dalteparin. In patients with severe renal dysfunction, there was no significant difference in any VTE (10.0% vs. 6.4%; p = 0.07) or major bleeding (8.9% vs. 11.0%; p = 0.66) but an increase in DVT with dalteparin (7.6% vs. 3.7%; p = 0.04). Interaction p-values for comparisons of HRs (ESRD versus not) were non-significant. CONCLUSIONS: In critically ill patients with ESRD, or severe renal dysfunction, there was no significant difference in any VTE or major bleeding between UFH and dalteparin. Patients with severe renal dysfunction who received dalteparin had more proximal DVTs than those on UFH; this finding did not hold in patients with ESRD alone
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
