Tromboprofilaxia venosa em pacientes clínicos: análise de sua aplicação

Role of ambulation to prevent venous thromboembolism in medical patients: where do we stand?

Venous thromboembolism (VTE) encompasses the spectrum of manifestations of deep venous thrombosis and/or pulmonary embolism and is a common, serious, and preventable complication in hospitalized patients. Although immobility plays an important role in determining VTE risk in medical patients, no clear and uniform criteria exist to guide clinicians in assessing immobility. The variation in the descriptions that do exist makes it difficult to interpret and compare the results of randomized clinical trials with respect to the influence of different levels of immobility on the magnitude of VTE risk and the role that early ambulation as an isolated factor plays in prevention of such events. Understanding these limitations is a prerequisite for the proper use and interpretation of VTE risk assessment tools and for indicating the best strategy for preventing venous thrombosis in hospitalized medical patients. The objective of this study was to review the main evidence reported in the literature on the role of ambulation in prevention of VTE.

Effectiveness of interventions for the implementation of thromboprophylaxis in hospitalised patients at risk of venous thromboembolism: an updated abridged Cochrane systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To assess the effectiveness of system-wide interventions designed to increase the implementation of thromboprophylaxis and decrease the incidence of venous thromboembolism (VTE) in hospitalised medical and surgical patients at risk of VTE.

DESIGN

Systematic review and meta-analysis of randomised controlled trials (RCTs).

DATA SOURCES

Medline, PubMed, Embase, BIOSIS, CINAHL, Web of Science, CENTRAL, DARE, EED, LILACS and clinicaltrials.gov without language restrictions from inception to 7 January 2017, as well as the reference lists of relevant review articles.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

RCTs that evaluated the effectiveness of system-wide interventions such as alerts, multifaceted, education, and preprinted orders when compared with no intervention, existing policy or another intervention.

RESULTS

We included 13 RCTs involving 35 997 participants. Eleven RCTs had data available for meta-analysis. Compared with control, we found absolute increase in the prescription of prophylaxis associated with alerts (21% increase, 95% CI [15% to 275%]) and multifaceted interventions (4% increase, 95% CI [3% to 11%]), absolute increase in the prescription of appropriate prophylaxis associated with alerts (16% increase, 95% CI [12% to 20%]) and relative risk reductions (risk ratio 64%, 95% CI [47% to 86%]) in the incidence of symptomatic VTE associated with alerts. Computer alerts were found to be more effective than human alerts, and multifaceted interventions with an alert component appeared to be more effective than multifaceted interventions without, although comparative pooled analyses were not feasible. The quality of evidence for improvement in outcomes was judged to be low to moderate certainty.

CONCLUSIONS

Alerts increased the proportion of patients who received prophylaxis and appropriate prophylaxis, and decreased the incidence of symptomatic VTE. Multifaceted interventions increased the proportion of patients who received prophylaxis but were found to be less effective than alerts interventions.

TRIAL REGISTRATION NUMBER

CD008201.

Interventions for implementation of thromboprophylaxis in hospitalized patients at risk for venous thromboembolism

BACKGROUND

Venous thromboembolism (VTE) is a leading cause of morbidity and mortality in hospitalized patients. While numerous randomized controlled trials (RCTs) have shown that the appropriate use of thromboprophylaxis in hospitalized patients at risk for VTE is safe, effective, and cost-effective, thromboprophylaxis remains underused or inappropriately used. Our previous review suggested that system-wide interventions, such as education, alerts, and multifaceted interventions were more effective at improving the prescribing of thromboprophylaxis than relying on individual providers' behaviors. However, 47 of the 55 included studies in our previous review were observational in design. Thus, an update to our systematic review, focused on the higher level of evidence of RCTs only, was warranted.

OBJECTIVES

To assess the effects of system-wide interventions designed to increase the implementation of thromboprophylaxis and decrease the incidence of VTE in hospitalized adult medical and surgical patients at risk for VTE, focusing on RCTs only.

SEARCH METHODS

Our research librarian conducted a systematic literature search of MEDLINE Ovid, and subsequently translated it to CENTRAL, PubMed, Embase Ovid, BIOSIS Previews Ovid, CINAHL, Web of Science, the Database of Abstracts of Reviews of Effects (DARE; in the Cochrane Library), NHS Economic Evaluation Database (EED; in the Cochrane Library), LILACS, and clinicaltrials.gov from inception to 7 January 2017. We also screened reference lists of relevant review articles. We identified 12,920 potentially relevant records.

SELECTION CRITERIA

We included all types of RCTs, with random or quasi-random methods of allocation of interventions, which either randomized individuals (e.g. parallel group, cross-over, or factorial design RCTs), or groups of individuals (cluster RCTs (CRTs)), which aimed to increase the use of prophylaxis or appropriate prophylaxis, or decrease the occurrence of VTE in hospitalized adult patients. We excluded observational studies, studies in which the intervention was simply distribution of published guidelines, and studies whose interventions were not clearly described. Studies could be in any language.

DATA COLLECTION AND ANALYSIS

We collected data on the following outcomes: the number of participants who received prophylaxis or appropriate prophylaxis (as defined by study authors), the occurrence of any VTE (symptomatic or asymptomatic), mortality, and safety outcomes, such as bleeding. We categorized the interventions into alerts (computer or human alerts), multifaceted interventions (combination of interventions that could include an alert component), educational interventions (e.g. grand rounds, courses), and preprinted orders (written predefined orders completed by the physician on paper or electronically). We meta-analyzed data across RCTs using a random-effects model. For CRTs, we pooled effect estimates (risk difference (RD) and risk ratio (RR), with 95% confidence interval (CI), adjusted for clustering, when possible. We pooled results if three or more trials were available for a particular intervention. We assessed the certainty of the evidence according to the GRADE approach.

MAIN RESULTS

From the 12,920 records identified by our search, we included 13 RCTs (N = 35,997 participants) in our qualitative analysis and 11 RCTs (N = 33,207 participants) in our meta-analyses.

PRIMARY OUTCOME

Alerts were associated with an increase in the proportion of participants who received prophylaxis (RD 21%, 95% CI 15% to 27%; three studies; 5057 participants; I² = 75%; low-certainty evidence). The substantial statistical heterogeneity may be in part explained by patient types, type of hospital, and type of alert. Subgroup analyses were not feasible due to the small number of studies included in the meta-analysis.Multifaceted interventions were associated with a small increase in the proportion of participants who received prophylaxis (cluster-adjusted RD 4%, 95% CI 2% to 6%; five studies; 9198 participants; I² = 0%; moderate-certainty evidence). Multifaceted interventions with an alert component were found to be more effective than multifaceted interventions that did not include an alert, although there were not enough studies to conduct a pooled analysis.

SECONDARY OUTCOMES

Alerts were associated with an increase in the proportion of participants who received appropriate prophylaxis (RD 16%, 95% CI 12% to 20%; three studies; 1820 participants; I² = 0; moderate-certainty evidence). Alerts were also associated with a reduction in the rate of symptomatic VTE at three months (RR 64%, 95% CI 47% to 86%; three studies; 5353 participants; I² = 15%; low-certainty evidence). Computer alerts were associated with a reduction in the rate of symptomatic VTE, although there were not enough studies to pool computer alerts and human alerts results separately.

AUTHORS' CONCLUSIONS

We reviewed RCTs that implemented a variety of system-wide strategies aimed at improving thromboprophylaxis in hospitalized patients. We found increased prescription of prophylaxis associated with alerts and multifaceted interventions, and increased prescription of appropriate prophylaxis associated with alerts. While multifaceted interventions were found to be less effective than alerts, a multifaceted intervention with an alert was more effective than one without an alert. Alerts, particularly computer alerts, were associated with a reduction in symptomatic VTE at three months, although there were not enough studies to pool computer alerts and human alerts results separately.Our analysis was underpowered to assess the effect on mortality and safety outcomes, such as bleeding.The incomplete reporting of relevant study design features did not allow complete assessment of the certainty of the evidence. However, the certainty of the evidence for improvement in outcomes was judged to be better than for our previous review (low- to moderate-certainty evidence, compared to very low-certainty evidence for most outcomes). The results of our updated review will help physicians, hospital administrators, and policy makers make practical decisions about adopting specific system-wide measures to improve prescription of thromboprophylaxis, and ultimately prevent VTE in hospitalized patients.

Level of concordance between two risk-assessment models for predicting venous thromboembolism in medical patients at admission

Objectives

To evaluate the level of concordance between the 2007 PRETEMED guidelines and the 2012 American College of Chest Physicians (ACCP) guidelines in medical patients at admission.

Methods

A cross-sectional, observational and descriptive study was designed and included all adult medical patients admitted from an emergency department. Firstly, patients classified as low-moderate risk and high risk according to PRETEMED were compared to those classified by ACCP as low and high risk. Secondly, the same analysis was performed but this time low and moderate-high risk patients according to PRETEMED were compared to ACCP low and high risk patients. The level of concordance was calculated using the kappa concordance index. The study was approved by the Ethics Committee for Clinical Research of the hospital.

Results

The analysis was performed with 207 patients; 53.1% were male and the median age was 75.3 years (minimum 18, maximum 100 years old). The most common diagnosis at admission was related to a respiratory disease (37.2%). The level of concordance was 0.59 (95% CI 0.48 to 0.70) when moderate risk patients were grouped with low-risk patients and 0.53 (95% CI 0.42 to 0.65) when moderate risk patients were grouped with high-risk patients.

Conclusions

The level of concordance between both guides is moderate. It would be helpful to confirm whether the level of agreement improves when the patient's condition stabilises after several days of hospitalisation.

Venous thrombosis

Venous thromboembolism (VTE) encompasses deep-vein thrombosis (DVT) and pulmonary embolism. VTE is the leading cause of lost disability-adjusted life years and the third leading cause of cardiovascular death in the world. DVT leads to post-thrombotic syndrome, whereas pulmonary embolism can cause chronic pulmonary hypertension, both of which reduce quality of life. Genetic and acquired risk factors for thrombosis include non-O blood groups, factor V Leiden mutation, oral contraceptive use, hormone replacement therapy, advanced age, surgery, hospitalization and long-haul travel. A combination of blood stasis, plasma hypercoagulability and endothelial dysfunction is thought to trigger thrombosis, which starts most often in the valve pockets of large veins. Animal studies have revealed pathogenic roles for leukocytes, platelets, tissue factor-positive microvesicles, neutrophil extracellular traps and factors XI and XII. Diagnosis of VTE requires testing and exclusion of other pathologies, and typically involves laboratory measures (such as D-dimer) and diagnostic imaging. VTE is treated with anticoagulants and occasionally with thrombolytics to prevent thrombus extension and to reduce thrombus size. Anticoagulants are also used to reduce recurrence. New therapies with improved safety profiles are needed to prevent and treat venous thrombosis. For an illustrated summary of this Primer, visit: http://go.nature.com/8ZyCuY.

Risk factors in venous thromboembolism in hospitalized patients

Venous thromboembolism (VTE) causes considerable morbidity and mortality. About half of all VTE cases in adults are related to recent hospitalization, in spite of the clinical guidelines regarding prophylaxis. We aimed to assess the frequency and the independent risk factors in VTE in hospitalized patients, and to compare the risk factors in medical versus surgical cases. A case-control study consisting of 732 patients (382 with VTE and 350 controls) was designed. At least one risk factor was found in 90.31% of VTE cases; more than half of the patients presented multiple risk factors, associated with a double risk comparatively to the intervention of only one factor. A similar distribution of the risk factors was found in both medical and surgical patients, except for congestive cardiac failure (predominant in medical cases) and respectively, varicose veins, previous episode of VTE and cancer (predominant in surgical VTE patients). The independent risk factors in VTE were the following: previous episode of VTE, obesity, chronic obstructive pulmonary disease, congestive cardiac failure, varicose veins and cancer. The study shows the importance of the risk factors in VTE and the need to detect hospitalized patients at risk in both medical and surgical cases.