Medical admission order sets to improve deep vein thrombosis prevention: a model for others or a prescription for mediocrity?

Predictors of Symptomatic Venous Thromboembolism in Patients with Soft Tissue Sarcoma in the Lower Extremity

Orthopedic surgery and soft-tissue sarcoma (STS) both independently increase the risk of developing symptomatic venous thromboembolic events (SVTE), but there are no established risk factors or guidelines for how to prophylactically treat patients with STS undergoing surgery. The objectives of this study were to (1) identify the prevalence of SVTE in patients undergoing STS surgery, (2) identify risk factors for SVTE, and (3) determine the risk of wound complications associated with VTE prophylaxis. This retrospective study was conducted in a tertiary level, academic hospital. A total of 642 patients were treated for soft-tissue sarcoma in the lower extremity with follow up for at least 90 days for the development of SVTE such as deep venous thrombosis and pulmonary embolism. Multivariate logistic regression was used to identify predictors for these events by controlling for patient characteristics, surgical characteristics, and treatment variables, with significance held at p < 0.05. Twenty eight patients (4.36%) were diagnosed with SVTE. Multivariate analysis found six significant predictors ordered based on standardized coefficients: pre-operative (PTT) partial thromboplastin time (p < 0.001), post-operative PTT (p = 0.010), post-op chemotherapy (p = 0.013), metastasis at diagnosis (p = 0.025), additional surgery for metastasis or local recurrence (p = 0.004), and tumor size larger than 10 cm (p < 0.001). The risk of wound complications (p = 0.04) and infection (p = 0.017) increased significantly in patients who received chemical prophylaxis. Our study identifies risk factors for patients at increased risk of developing VTE. Further prospective research is necessary to identify which protocols would be beneficial in preventing SVTE in high-risk patients with a low profile of wound complications.

Extended thromboprophylaxis in the acutely ill medical patient after hospitalization - a paradigm shift in post-discharge thromboprophylaxis

Venous thromboembolism (VTE) is a significant healthcare burden with approximately 900,000 events annually in the United States, over half of which are healthcare-associated. This number is anticipated to double by 2050. Group prophylaxis strategies confined to the inpatient setting appear to have minimal impact on the reduction of post-discharge VTE in medically ill patients due to shortened lengths of stay and a heterogenous population that includes patients at low risk for VTE. In accordance with current guideline recommendations, very few (<5%) medically ill patients are discharged with extended prophylaxis, which potentially creates a clinical gap for at-risk patients as VTE risk has been shown to persist for up to 90 days. Initial studies of extended thromboprophylaxis in acutely ill medical patients with enoxaparin, rivaroxaban and apixaban showed little to no benefit towards VTE reduction that was consistently outweighed by increased bleeding. The more recent APEX study that compared betrixaban to enoxaparin in an enriched patient population at high-risk for VTE was the first study of extended thromboprophylaxis that showed similar efficacy in VTE prevention without an increase in major bleeding. Based on the APEX results, betrixaban recently gained FDA approval for extended thromboprophylaxis in acutely ill medical patients. Recognition that up to half of medically ill patients are not at sufficient risk to warrant thromboprophylaxis has driven extensive research towards development of scientifically derived and validated VTE risk assessment models intended to identify patients who do not warrant prophylaxis, as well as those at high risk who may derive benefit from extended thromboprophylaxis. This article will review prior and ongoing extended thromboprophylaxis studies, VTE and bleed risk assessment models, incorporation of biomarkers in VTE risk assessment and key issues in the paradigm shift towards individualized VTE prophylaxis in acutely ill medical patients.

Assessing the Caprini Score for Risk Assessment of Venous Thromboembolism in Hospitalized Medical Patients

BACKGROUND

The optimal approach to assess risk of venous thromboembolism in hospitalized medical patients is unknown. We examined how well the Caprini risk assessment model predicts venous thromboembolism in hospitalized medical patients.

METHODS

Between January 2011 and March 2014, venous thromboembolism events and risk factors were collected from non-intensive care unit medical patients hospitalized in facilities across Michigan. After calculation of the Caprini score for each patient, mixed logistic spline regression was used to determine the predicted probabilities of 90-day venous thromboembolism by receipt of pharmacologic prophylaxis across the Caprini risk continuum.

RESULTS

A total of 670 (1.05%) of 63,548 eligible patients experienced a venous thromboembolism event within 90 days of hospital admission. The mean Caprini risk score was 4.94 (range, 0-28). Predictive modeling revealed a consistent linear increase in venous thromboembolism for Caprini scores between 1 and 10; estimates beyond a score of 10 were unstable. Receipt of pharmacologic prophylaxis resulted in a modest decrease in venous thromboembolism risk (odds ratio, 0.85; 95% confidence interval, 0.72-0.99; P = .04). However, the low overall incidence of venous thromboembolism led to large estimates of numbers needed to treat to prevent a single venous thromboembolism event. A Caprini cut-point demonstrating clear benefit of prophylaxis was not detected.

CONCLUSIONS

Although a linear association between the Caprini risk assessment model and the risk of venous thromboembolism was noted, an extremely low incidence of venous thromboembolism events in non-intensive care unit medical patients was observed. The Caprini risk assessment model was unable to identify a subset of medical patients who benefit from pharmacologic prophylaxis.

Default options in the ICU: widely used but insufficiently understood

PURPOSE OF REVIEW

Default options dramatically influence the behavior of decision makers and may serve as effective decision support tools in the ICU. Their use in medicine has increased in an effort to improve efficiency, reduce errors, and harness the potential of healthcare technology.

RECENT FINDINGS

Defaults often fall short of their predicted influence when employed in critical care settings as quality improvement interventions. Investigations reporting the use of defaults are often limited by variations in the relative effect across sites. Preimplementation experiments and long-term monitoring studies are lacking.

SUMMARY

Defaults in the ICU may help or harm patients and clinical efficiency depending on their format and use. When constructing and encountering defaults, providers should be aware of their powerful and complex influences on decision making. Additional evaluations of the appropriate creation of healthcare defaults and their resulting intended and unintended consequences are needed.

Venous thromboembolism prevention guidelines for medical inpatients: mind the (implementation) gap

BACKGROUND

Hospital-associated nonsurgical venous thromboembolism (VTE) is an important problem addressed by new guidelines from the American College of Physicians (ACP) and American College of Chest Physicians (AT9).

METHODS

Narrative review and critique.

RESULTS

Both guidelines discount asymptomatic VTE outcomes and caution against overprophylaxis, but have different methodologies and estimates of risk/benefit. Guideline complexity and lack of consensus on VTE risk assessment contribute to an implementation gap. Methods to estimate prophylaxis benefit have significant limitations because major trials included mostly screening-detected events. AT9 relies on a single Italian cohort study to conclude that those with a Padua score ≥4 have a very high VTE risk, whereas patients with a score <4 (60% of patients) have a very small risk. However, the cohort population has less comorbidity than US inpatients, and over 1% of patients with a score of 3 suffered pulmonary emboli. The ACP guideline does not endorse any risk-assessment model. AT9 includes the Padua model and Caprini point-based system for nonsurgical inpatients and surgical inpatients, respectively, but there is no evidence they are more effective than simpler risk-assessment models.

CONCLUSIONS

New VTE prevention guidelines provide varied guidance on important issues including risk assessment. If Padua is used, a threshold of 3, as well as 4, should be considered. Simpler VTE risk-assessment models may be superior to complicated point-based models in environments without sophisticated clinical decision support.

Optimizing prevention of hospital-acquired venous thromboembolism (VTE): prospective validation of a VTE risk assessment model

BACKGROUND

Hospital-acquired (HA) venous thromboembolism (VTE) is a common source of morbidity/mortality. Prophylactic measures are underutilized. Available risk assessment models/protocols are not prospectively validated.

OBJECTIVES

Improve VTE prophylaxis, reduce HA VTE, and prospectively validate a VTE risk-assessment model.

DESIGN

Observational design.

SETTING

Academic medical center.

PATIENTS

Adult inpatients on medical/surgical services.

INTERVENTIONS

A simple VTE risk assessment linked to a menu of preferred VTE prophylaxis methods, embedded in order sets. Education, audit/feedback, and concurrent identification of nonadherence.

MEASUREMENTS

Randomly sampled inpatient audits determined the percent of patients with "adequate" VTE prevention. HA VTE cases were identified concurrently via digital imaging system. Interobserver agreement for VTE risk level and judgment of adequate prophylaxis were calculated from 150 random audits.

RESULTS

Interobserver agreement with 5 observers was high (kappa score for VTE risk level = 0.81, and for judgment of "adequate" prophylaxis = 0.90). The percent of patients on adequate prophylaxis improved each of the 3 years (58%, 78%, and 93%; P < 0.001) and reached 98% in the last 6 months of 2007; 361 cases of HA VTE occurred over 3 years. Significant reductions for the risk of HA VTE (risk ratio [RR] = 0.69; 95% confidence interval [CI] = 0.47-0.79) and preventable HA VTE (RR = 0.14; 95% CI = 0.06-0.31) occurred. We detected no increase in heparin-induced thrombocytopenia (HIT) or prophylaxis-related bleeding using administrative data/chart review.

CONCLUSIONS

We prospectively validated a VTE risk-assessment/prevention protocol by demonstrating ease of use, good interobserver agreement, and effectiveness. Improved VTE prophylaxis resulted in a substantial reduction in HA VTE.

Prevention of venous thromboembolism in Department of Veterans Affairs hospitals

BACKGROUND

Pulmonary embolism (PE) is the most common preventable cause of death in hospitals, but many patients do not receive proven preventive therapies.

OBJECTIVE

To ascertain the extent to which inpatients received therapies for the prevention of venous thromboembolism (VTE).

DESIGN

Medical records review of a random sample of hospitalized patients, stratified by hospital teaching status.

SETTING

Department of Veterans Affairs (VA) acute-care hospitals.

PATIENTS

Two groups hospitalized >or=48 hours during the year ending March 31, 2007: (1) all 4963 patients older than 74 years with a principal discharge diagnosis of heart failure; and (2) all 1448 patients with any discharge diagnosis of PE.

MEASUREMENTS

Rate of VTE preventive care.

RESULTS

Sixty-three of the 100 randomly selected heart failure patients had adequate anticoagulation, 29 (46%) of whom were taking warfarin for chronic conditions. For patients discharged with a PE diagnosis, records from all 330 nonteaching and 449 (40%) teaching hospital cases were reviewed. Most cases (698; 90%) were excluded because there was only a remote history of PE or the diagnosis was made prior to admission. Thirty-four of the 63 patients (54%) with confirmed in-hospital PE and unequivocal VTE risk factors received appropriate preventive treatment. Thirty of the 66 patients (48%) with missed opportunities for prevention had inappropriate mechanical prophylaxis or inadequate use of anticoagulation.

CONCLUSIONS

In hospitalized veterans with PE or at risk for VTE, missed opportunities for prevention were frequent and included inappropriate or inadequate interventions. Retrospective chart review was an inefficient method for identifying patients with in-hospital PE.