Safety and Efficacy of Prophylactic Enoxaparin Adjusted by Anti-Factor Xa Peak Levels in Pancreatic Surgery

BACKGROUND

Recommended prophylactic doses of enoxaparin (Lovenox) are associated with subprophylactic anti-Factor Xa (anti-Xa) levels. This study examines the safety and efficacy of anti-Xa-guided dosing of enoxaparin in pancreatic surgery.

METHODS

Prospectively enrolled patients undergoing pancreatic surgery received enoxaparin dosing adjusted based on peak anti-Xa levels and were compared to a historical cohort of patients.

RESULTS

Baseline characteristics were similar between the intervention and control groups. In the intervention group, 73.9% initially had subprophylactic peak anti-Xa levels. There were no differences in the venous thromboembolism (VTE) rates between the intervention and control groups (0% vs. 7.69%; P = .084), major bleeding events (4.35% vs. 2.56%; P = .627), RBC transfusion (15.2% vs. 25.6%; P = .257), or Hgb on discharge (9.82 vs. 9.44 g/dL; P = .244). Subtherapeutic anti-Xa levels were correlated with a higher BMI (P = .033), longer OR time (P = .011), and length of stay (P = .018).

CONCLUSIONS

Enoxaparin 40 mg once daily is associated with subprophylactic peak anti-Xa levels. Dose adjustment based on anti-Xa levels trended toward a lower rate of in-hospital VTE without an increase in bleeding or transfusion requirement.

Extensive Lower Limb Deep Vein Thrombosis Provoked by Gastroenteritis-Induced Dehydration: A Case Report for Unusual Precipitating Factor

The incidence of deep vein thrombosis (DVT) has been related to a number of risk factors, including genetic and acquired prothrombotic conditions, infections, inflammatory diseases, hematologic disorders, trauma, and drug use. Dehydration is a known independent risk factor for the development of thrombosis; however possibly insufficient evidence to form a strong association. The purpose of this case report is to present a 30-year-old male with DVT provoked by acute gastroenteritis-induced dehydration. The patient presented to the emergency department (ED) with a recent history of watery diarrhea for four days, for which he was diagnosed with gastroenteritis and managed at an outpatient care facility. The patient visited the ED again with a complaint of a one-day history of progressively worsening continuous pain in his left lower calf associated with swelling. The ultrasound-Doppler/duplex scan for the left lower limb venous system showed negative augmentation signs and non-compressibility of the deep venous system with partial occlusion/echogenic thrombosis extending from the external iliac vein, saphenofemoral junction, superficial femoral vein, popliteal vein, anterior tibial vein, and posterior tibial artery vena comitans. The patient was diagnosed with acute extensive DVT (multiple emboli). Patient care (medical treatment plan/therapeutic anticoagulation) was started in the ED and continued in the Critical Care Unit for close monitoring and care for a couple of days, after which he was transferred to the ward and then discharged in stable condition. He was prescribed a three-month course of appropriate medication regimen. This rare case presentation is a reminder to emergency physicians that dehydration might induce DVT and all patients, regardless of age, diagnosis or comorbidities, should always be risk assessed upon presentation and discharge, and prophylaxis should be provided according to their risk profile.

Intermittent Pneumatic Compression in Addition to Standard Prophylaxis of Postoperative Venous Thromboembolism in Extremely High-risk Patients (IPC SUPER): A Randomized Controlled Trial

OBJECTIVE

To assess the efficacy of adjunctive IPC to standard prophylaxis of postoperative VTE in patients at extremely high-risk.

SUMMARY OF BACKGROUND DATA

The standard prophylaxis for postoperative VTE is insufficient in extremely high-risk patients. It is unclear whether an adjunctive use of IPC would result in a lower incidence of postoperative venous thrombosis.

METHODS

We randomly assigned patients who underwent major surgery and had a Caprini score of ≥11 to receive either IPC in addition to standard prophylaxis with anti-embolic stockings (pressure of 18-21 mm Hg at the ankle) and low-molecular-weight heparin (IPC group) or standard prophylaxis alone (control group). The primary outcome was an asymptomatic venous thrombosis of the lower limbs, as detected by duplex ultrasound scan performed before inclusion and every 3-5 days after surgery.

RESULTS

A total of 407 patients underwent randomization, of which 204 were assigned to the IPC group and 203 to the control group. The primary outcome occurred in 1 (0.5%) patient in the IPC group and 34 (16.7%) patients in the control group [relative risk, 0.03, 95% confidential interval (CI): 0.01-0.21]. Pulmonary embolism occurred in none of the 204 patients in the IPC group and in 5 (2.5%) patients in the control group (relative risk, 0.09; 95% CI, 0.01-1.63), and postoperative death occurred in 6 (2.9%) patients in the IPC group and 10 (4.9%) in the control group (relative risk, 0.50; 95% CI, 0.50-1.60).

CONCLUSIONS

Among patients with a Caprini score of ≥11 who received standard prophylaxis for VTE, adjunctive IPC resulted in a significantly lower incidence of asymptomatic venous thrombosis.

Call to Action to Prevent Venous Thromboembolism in Hospitalized Patients: A Policy Statement From the American Heart Association

Venous thromboembolism (VTE) is a major preventable disease that affects hospitalized inpatients. Risk stratification and prophylactic measures have good evidence supporting their use, but multiple reasons exist that prevent full adoption, compliance, and efficacy that may underlie the persistence of VTE over the past several decades. This policy statement provides a focused review of VTE, risk scoring systems, prophylaxis, and tracking methods. From this summary, 5 major areas of policy guidance are presented that the American Heart Association believes will lead to better implementation, tracking, and prevention of VTE events. They include performing VTE risk assessment and reporting the level of VTE risk in all hospitalized patients, integrating preventable VTE as a benchmark for hospital comparison and pay-for-performance programs, supporting appropriations to improve public awareness of VTE, tracking VTE nationwide with the use of standardized definitions, and developing a centralized data steward for data tracking on VTE risk assessment, prophylaxis, and rates.

Utilization of the Caprini score in conjunction with thrombodynamic testing reduces the number of unpredicted postoperative venous thromboembolism events in patients with colorectal cancer

BACKGROUND

The thrombodynamic test (TD) is a novel global test of hemostasis that allows to study the spatial-temporal characteristics of a clot formation in real time under conditions close to natural ones and demonstrates high sensitivity to detect the state of hypercoagulation. The main paraments of the test are the velocity of clot growth, clot's size, and clot density. The objective of this study was to compare the classic Caprini 2005 score and its modified version in association with the results of TD. The goal is to predict postoperative venous thromboembolism (VTE) in surgical patients undergoing surgery for colorectal cancer.

METHODS

This was a prospective observational clinical study involving 80 patients (33 men and 47 women; mean age, 73.9 ± 7.2 years) who underwent major (79 cases) or minor (1 case) surgery for colorectal cancer. Patients were at high risk for postoperative VTE (ie, a mean Caprini score of 9.9 ± 2.0) and received combined prophylaxis (ie, antiembolic compression stockings and enoxaparin 40 mg once daily) until discharge. Enoxaparin was administered at a fixed time of blood sampling for the TD test. Duplex ultrasound scan was performed to detect postoperative vein thrombosis before and 5 to 7 days after surgery.

RESULTS

Postoperative vein thrombosis was found in 21 of 80 patients (26.3%; 95% confidence interval, 17.9%-36.8%). Regression analysis and receiver operating characteristic (ROC) curve showed that Caprini scores significantly predicted VTE (P < .0001; area under the curve [AUC] = 0.839 ± 0.045). Analysis of ROC curve coordinates showed that a cutoff point of 11 scores had a sensitivity of 76.2% and a specificity of 74.6%. The results of the TD test showed significant hypercoagulation despite enoxaparin administration in patients with VTE. Regression analysis and ROC curves demonstrated that the following TD parameters had the greatest predictability for postoperative DVT: initial velocity of clot growth (Vin) and clot size (CS) measured at 12 hours after enoxaparin administration (AUC, 0.697 ± 0.063 and AUC, 0.790 ± 0.059, respectively), as well as Vin and CS measured 24 hours after the enoxaparin injection (S = 0.847 ± 0.059 and S = 0.803 ± 0.069, respectively). The cutoff points for VTE prediction at 12 and 24 hours seemed to be a Vin of greater than 62.5 and greater than 64.5 μm/minute (normal range, 35-56 μm/minute) as well as a CS of greater than 1351.5 and greater than 1333.5 μm (normal range, 800-1200 μm), respectively. Identified thresholds for TD parameters have been integrated into Caprini scores under the item "other congenital or acquired thrombophilia." The total Caprini scores were recalculated in patients where one or all TD parameters had exceeded the cutoff followed by reanalysis of the ROC curves. The best predictability was found for Caprini scores considering the elevation of all four TD parameters (AUC, 0.924 ± 0.029) with increased cutoff to a score of 12 with a sensitivity of 85.7% and a specificity of 81.4%. The use of cutoffs for the original and modified scores could be used to calculate the number of patients that were under cutoff but developed with VTE: 10.2% and 5.9%, respectively.

CONCLUSIONS

Integrating TD parameters into the Caprini score increases the ability to predict postoperative 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.

Magnitude of Venous Thromboembolism Risk in US Hospitals: Impact of Evolving National Guidelines for Prevention of Venous Thromboembolism

BACKGROUND

The annual number of US hospital discharges at risk for venous thromboembolism and the impact of evolving American College of Chest Physicians (ACCP) consensus guidelines for prevention of venous thromboembolism are unknown.

METHODS

Three risk-assessment algorithms based on 2004, 2008, and 2012 ACCP guidelines for prevention of venous thromboembolism were applied to the 2014 US National Inpatient Sample to derive estimates of the annual number of US inpatients at risk for venous thromboembolism.

RESULTS

Of 35.4 million discharges from US acute-care hospitals in 2014, 25.3 million (71%) met study inclusion criteria of age ≥18 years and length of stay (LOS) ≥2 days. Among 7.5 million patients who underwent a procedure in an operating room, more than 4.4 million (59%) were at ACCP-defined risk for venous thromboembolism, irrespective of which version of the ACCP guidelines applied. With an additional 8.4/8.5/7.3 million eligible discharges meeting criteria for venous thromboembolism prophylaxis due to medical risk factors, the total annual numbers of inpatients at risk for venous thromboembolism were 12.8/12.9/11.7 million according to 2004/2008/2012 ACCP guidelines, respectively.

CONCLUSIONS

Over half of adult patients who had an LOS ≥2 days in US acute-care hospitals met ACCP criteria for consideration of venous thromboembolism prophylaxis based on risk factors associated with surgery or acute medical illness. These data provide an objective basis for estimating the potential impact of venous thromboembolism prevention on patient care, together with associated costs, risks, and benefits.

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.

Thromboprophylaxis Failure in the Adult Medical Inpatient

Venous thromboembolism (VTE), a leading cause of morbidity and mortality among hospitalized patients, is often due to prophylaxis failure rather than omission, but few studies have identified the risk factors for failure. Risk factors for thromboprophylaxis failure include personal or family history of VTE, use of vasopressors or inotropes, increased body mass index, cranial surgery, intensive care patient, leukocytosis, indwelling central venous catheter and admission from a long-term care facility. Identifying patients at risk for thromboprophylaxis failure should prompt close observation during hospitalization for signs of VTE, close observation after discharge and potentially more aggressive prophylaxis strategies, although no specific guidelines exist for medical patients at this time.

Reasons for the persistent incidence of venous thromboembolism

Reasons for trends in venous thromboembolism (VTE) incidence are uncertain. It was our objective to determine VTE incidence trends and risk factor prevalence, and estimate population-attributable risk (PAR) trends for each risk factor. In a population-based cohort study of all residents of Olmsted County, Minnesota from 1981-2010, annual incidence rates were calculated using incident VTE cases as the numerator and age- and sex-specific Olmsted County population estimates as the denominator. Poisson regression models were used to assess the relationship of crude incidence rates to year of diagnosis, age at diagnosis, and sex. Trends in annual prevalence of major VTE risk factors were estimated using linear regression. Poisson regression with time-dependent risk factors (person-years approach) was used to model the entire population of Olmsted County and derive the PAR. The age- and sex-adjusted annual VTE incidence, 1981-2010, did not change significantly. Over the time period, 1988-2010, the prevalence of obesity, surgery, active cancer and leg paresis increased. Patient age, hospitalisation, surgery, cancer, trauma, leg paresis and nursing home confinement jointly accounted for 79 % of incident VTE; obesity accounted for 33 % of incident idiopathic VTE. The increasing prevalence of obesity, cancer and surgery accounted in part for the persistent VTE incidence. The PAR of active cancer and surgery, 1981-2010, significantly increased. In conclusion, almost 80 % of incident VTE events are attributable to known major VTE risk factors and one-third of incident idiopathic VTE events are attributable to obesity. Increasing surgery PAR suggests that concurrent efforts to prevent VTE may have been insufficient.

The impact of the DoH Commissioning for Quality and Innovation incentive on the success of venous thromboembolism risk assessment in hospitalised patients. A single institution experience in a quality outcome improvement over a 4-year cycle

OBJECTIVES

To i) demonstrate compliance with the Commissioning for Quality and Innovation for venous thromboembolism risk assessment ii) to undertake root cause analysis of Hospital Acquired Thrombosis and to investigate its impact on quality of care.

DESIGN

Prospective monitoring of all admissions.

SETTING

Imperial College Healthcare Hospitals, London.

PARTICIPANTS

All Hospital Provider Spells as defined on the NHS Data Model and Dictionary.

MAIN OUTCOME MEASURES

i) Percentage of patients undergoing Venous Thromboembolism Risk Assessment (VTE-RA) at and 24-hours after admission ii) root cause analysis of Hospital Acquired Thrombosis up to 90 days following discharge.

RESULTS

Over a 48-month cycle 83% were overall VTE-RA assessed with 36% in the first 12 months but with significant improvement to ≥95% between April 2013 and April 2015, achieving compliance target since April 2012 involving a massive 633, 850 Spells over the 4 year period. We undertook root cause analysis of all VTE episodes from April 2013 to March 2014, to ascertain Hospital Acquired Thrombosis (HAT), we analysed 433, 174 inpatient days and found a HAT rate of 1 per 1000 with 23% and 24% for DVTs and PEs potentially avoidable respectively. We further analysed VTE risk stratification (n = 1000) and found 37.0% at high risk, 44.4% at medium risk and 18.6 % at low risk, indicating the need of thromboprophylaxis in 81.4% (high and medium) of whom 33.6% were excluded.

CONCLUSIONS

We achieved 95% RA compliance which has favourably impacted on our daily practice and improved the quality of the clinical care.

Validation of the Caprini risk assessment model for venous thromboembolism in high-risk surgical patients in the background of standard prophylaxis

OBJECTIVE

We used the Caprini venous thromboembolism risk assessment score to prospectively evaluate if there was a correlation between the Caprini scores and the incidence of postoperative deep vein thrombosis (DVT) in high-risk surgical patients. A second objective was to determine whether patients at extremely high risk need a more effective prophylactic regimen.

METHODS

This prospective multicenter observational study involved 140 high-risk patients who underwent abdominal (48%) or cranial and/or spinal (52%) surgery. All patients were assessed using the Caprini model and had a mean score of 9.5 ± 2.7 (range, 5-15). Our standard prophylaxis for venous thromboembolism consisted of above-knee graduated compression stockings with 18 to 21 mm Hg pressure and subcutaneous low-dose unfractionated heparin three times per day, starting on the first or second through the fifth postoperative day depending on the risk of bleeding. We performed a duplex ultrasound examination at baseline during the first 12 to 24 hours after surgery and then every 3 to 5 days until discharge to assess the lower limb venous system up to the inferior vena cava. The end point of the study was ultrasound verification of fresh DVT or pulmonary embolism (PE). Verification of PE was made in all cases of DVT using echocardiography, lung scintigraphy, combined single-photon emission computed tomography and X-ray computed tomography, or autopsy.

RESULTS

Fresh postoperative DVT was found in 39 patients (28%). The incidence of DVT was 2% in patients with a Caprini score of 5 to 8, 26% in patients with scores of 9 to 11, and 65% in patients with scores of 12 to 15 (P for trend < .01). The risk for DVT was increased 18.7-fold for patients with scores of 9 to 11 and 98.4-fold for scores of 12 to 15 compared with patients with scores of 5 to 8. The area under the receiver operating characteristic curve was 0.87 (95% confidence interval, 0.81-0.94) and a Caprini score of 11 was the cutoff point that provided the highest sensitivity combined with highest specificity. In the 77 patients with a score of <11, DVT occurred in 2 patients (3%). In contrast, in the 63 patients with a score of ≥ 11, DVT occurred in 37 patients (59%; P < .01). PE was found in 13 patients (9%) and confirmed with autopsy. In all cases, verified fresh DVT was the source of embolism.

CONCLUSIONS

There was a significant correlation between Caprini scores and the incidence of postoperative DVT in high-risk surgical patients. A Caprini score of ≥ 11 can identify a subgroup of patients at extremely high risk. These patients need a more effective prophylactic regimen.

New oral anticoagulants for the treatment of venous thromboembolism: understanding differences and similarities

Venous thromboembolism (VTE) is a major cause of morbidity, mortality, and healthcare expenditure. In the United States, approximately 0.1 % of the population experiences an initial VTE event each year. Anticoagulation therapy is the cornerstone of acute VTE treatment and for prevention of recurrent VTE events. Conventional anticoagulants, including heparin, low-molecular-weight heparins, fondaparinux, and vitamin K antagonists are widely used but have limitations. Newer oral anticoagulant agents, including direct thrombin inhibitors (e.g., dabigatran etexilate) and direct factor Xa inhibitors (e.g., rivaroxaban, apixaban, and edoxaban) have been developed to attempt to overcome some of the limitations of conventional anticoagulant therapy. These new oral agents have been evaluated for safety and efficacy in large, randomized clinical trials in the treatment and secondary prevention of VTE with results that are comparable to conventional therapy. Dabigatran, rivaroxaban, apixaban, and edoxaban are important new treatment options for patients with VTE. In this review, we compare these new agents and their associated clinical trials in VTE treatment.

Venous thromboembolism in Germany: results of the GermAn VTE registry (GATE-registry)

BACKGROUND

Despite the existence of active prophylaxis strategies for patients at risk of venous thromboembolism (VTE), people still suffer from this disease. To establish the setting in which VTE occurs and how it can be prevented, a study was conducted aimed at analysing the circumstances surrounding VTE development.

PATIENTS AND METHODS

In a nationwide study, 629 patients (54% female) with acute deep vein thrombosis (DVT) or pulmonary embolism (PE) were recruited consecutively at 17 centres (78.4% with DVT, 5.1% with PE, 16.5% with both). The physicians completed a standardised questionnaire together with the patients on the day the diagnosis was made, or a few days later. The following items were included: general information, circumstances that could increases VTE risk within the previous 6 weeks, action taken to prevent VTE within the previous 6 weeks, specific VTE risk factors. Patients were defined as being 'in a medical setting' if they had had contact with a physician within the 6-week period prior to VTE diagnosis.

RESULTS

A total of 286 (45.5%) patients were classified in a medical setting, but 343 (54.5%) patients were not. Of those who were not in a medical setting within the last six weeks, 12.0% had returned from a journey and 15.5% had restricted mobility. Of those within a medical setting, only 80 (28.0%) patients had received heparin as prophylaxis. Thus, the largest group of patients with VTE today is not within a medical setting. The next largest group of patients were in a medical setting but received no heparin as prophylaxis. Those with a failed or inadequate use of prophylaxis represented the smallest group.

DISCUSSION

More than 50% of those who have acute VTE are not being reached by our present day VTE prophylaxis strategies.

Experimental Validation of Methods for Prophylaxis against Deep Venous Thrombosis: A Review and Proposal

The experimental procedure by which the valve cusp hypoxia (VCH) hypothesis of the etiology of deep venous thrombosis (DVT) was confirmed lends itself to testing of methods of prophylaxis. Similar animal experiments could end the present exclusive reliance on statistical analysis of data from large patient cohorts to evaluate prophylactic regimes. The reduction of need for such (usually retrospective) analyses could enable rationally-based clinical trials of prophylactic methods to be conducted more rapidly, and the success of such trials would lead to decreased incidences of DVT-related mortality and morbidity. This paper reviews the VCH hypothesis ("VCH thesis", following its corroboration) and its implications for understanding DVT and its sequelae, and outlines the experimental protocol for testing prophylactic methods. The advantages and limitations of the protocol are briefly discussed.

A simple reminder system improves venous thromboembolism prophylaxis rates and reduces thrombotic events for hospitalized patients1

BACKGROUND

Compliance with venous thromboembolism (VTE) prophylaxis is poor.

OBJECTIVES

We sought to determine whether a simple electronic reminder applicable to all hospitalized patients would increase prophylaxis rates and reduce VTE rates.

METHODS

An electronic reminder was added to the electronic medical record admission note used by all services in our hospital. Prophylaxis, VTE and bleeding rates before and after implementation were compared. Data were analyzed with sas version 9.1.

RESULTS

Among all adult medical and surgical patients admitted to our hospital during the time periods studied, 42.8% (1236/2888) before and 60.0% (1410/2350) after the reminder was added received appropriate prophylaxis as per American College of Chest Physicians (ACCP) guidelines (P < 0.001). The difference reached significance for both medical (51.0% vs. 68.9%; P < 0.001) and surgical (48.0% vs. 61.0%; P < 0.001) services. Fewer patients were diagnosed with VTE after our reminder was added (1.1% vs. 0.3%; P = 0.001), and there was a trend towards fewer bleeds (1.1% vs. 0.6%; P = 0.09). The presence of the reminder was an independent predictor for prophylaxis being given (odds ratio [OR] 1.92, 95% confidence interval [CI] 1.70-2.18; P < 0.001), and was independently associated with a decreased risk for VTE (OR 0.30, 95% CI 0.14-0.64; P = 0.003) after adjustment for other VTE risk factors.

CONCLUSION

Adding an electronic reminder to the admission note improved prophylaxis rates and reduced VTE rates across services. The system is easily reproducible and applicable to other facilities. The improvement obtained was modest, so additional measures will probably be needed to optimize prophylaxis rates.

Deep vein thrombosis in a young marathon athlete

STUDY DESIGN

Resident's case problem.

BACKGROUND

A 21-year-old athletic male college student presented to a direct-access physical therapy clinic with complaints of left calf pain 4 days in duration. After initial examination, a working diagnosis of calf strain was formulated. Three days following initial examination, the patient reported 80% improvement in symptoms and was performing activities of daily living pain free. Four weeks later, the patient returned with complaints of reoccurring calf pain. The patient's signs, symptoms, and history at subsequent follow-up no longer presented a consistent clinical picture of calf strain; therefore, a D-dimer assay was ordered to rule out a deep vein thrombosis (DVT).

DIAGNOSIS

The D-dimer was elevated so the patient was admitted to the hospital and started on low-molecular-weight heparin. A compression ultrasound revealed an extensive left superficial femoral and popliteal DVT in this otherwise healthy athlete.

DISCUSSION

Lower extremity DVT is a serious and potentially fatal disorder. Physical therapists need to be diagnostically vigilant for vascular pathology in all patients with extremity pain and swelling. Employing the best current evidenced-based screening tools to rule out vascular pathology, such as deep and superficial vein pathology, should be the goal of every clinician. The Wells score is one such screening tool that has proven to be beneficial in this area. This case report presents a dilemma in diagnosis and illustrates the importance of revisiting differential diagnoses with each patient encounter. Clinicians must consider the possibility of a DVT with every patient seen with posterior leg pain.

LEVEL OF EVIDENCE

Diagnosis, level 4. doi:10.2519/jospt.2011.3823.