Regular ArticleLR–PED Rule: Low Risk Pulmonary Embolism Decision Rule – A new decision score for low risk Pulmonary Embolism
Introduction
Pulmonary embolism (PE) is a common and potentially lethal condition. Despite diagnostic advances in the last decades, delays in PE diagnosis are common and represent a very important issue, leading some authors to suggest public health and educational initiatives to improve efficiency in PE diagnosis [1].
Massive PE is one of the most prevalent causes of sudden death and this form of presentation is frequently the first manifestation of that condition [2]. However, non-massive PE is the most common form of presentation of PE, bearing a much lower mortality rate when appropriate anticoagulant therapy is started early (less than 5% in the first 3–6 months of treatment) [3]. Still, some patients initially considered to be low risk show progressive deterioration of their clinical condition, warranting the postponement of their discharge, with exponential increase in health care costs and hospital-acquired infection risk.
Over the past decade, subcutaneously low molecular weight heparins have replaced much of IV unfractionated heparin therapy and have facilitated outpatient deep vein thrombosis (DVT) therapy. Although most patients with acute PE remain hospitalized during initial therapy, some may be suitable for partial or complete outpatient management. However, a very small but significant proportion of patients with low risk acute PE will die or have hemorrhagic or thromboembolic complications during the initial therapy period or the subsequent months [4], [5], reinforcing the need for reliable prognostic information at presentation in order to risk stratify patients for ambulatory treatment. The new oral anticoagulants Dabigatran [6] and Rivaroxaban [7] have emerged as new ambulatory therapeutics for patients with venous thromboembolism.
Therebeing considerable interest in the identification of patients eligible for outpatient treatment, several authors have studied the application of particular analytical, clinical or angiographic prognostic markers [8], [9] or renowned PE risk scores for the prognostic stratification of low risk PE patients. Although the Well's criteria and the PERC rule have never been shown to have prognostic value in acute PE, the Geneva score, initially and primarily developed for diagnostic purposes [10], [11], has shown reasonable prognostic stratification accuracy in subsequent studies [4] and the Pulmonary Embolism Severity Index (PESI) score showed modest prognostic superiority compared to the Geneva rule [5]. Despite these advances, active research is ongoing for the development of new scores that can identify low risk acute PE patients with greater specificity, in order to reduce the tremendous health care costs associated to the inpatient treatment of this condition.
Therefore, this investigation aims at developing a new and improved score that allows detection of very low risk PE patients who are eligible for outpatient treatment.
Section snippets
Study Design
Retrospective cohort study that attempted to include all patients with a diagnosis of low risk acute PE between January 1, 2007, and April 30, 2011. Using collected baseline data at the time of PE diagnosis and outcome data from this cohort, we retrospectively assessed the Geneva and simplified PESI scores for all patients and their prognostic accuracy for predicting intrahospital, 1 month and 6 month mortality risk. We compared the ability of each score to predict primary or secondary endpoints
Results
Overall characteristics of the study population are shown on Table 1.
Intrahospital mortality rate was 11.3%, while 1-month and 6-month all cause mortality rates were 14.1% and 22.5%, respectively.
Discussion
Our sample included 142 hemodynamically stable patients with non-massive PE, asymptomatic or mildly symptomatic six hours following admission. Hypotension at any time during those first six hours or the documentation of clinical or echocardiographic signs of right ventricular dysfunction/overload were exclusion criteria, as these patients do not benefit from an early discharge. Patients in our sample were older and had a higher prevalence of most comorbid illnesses compared to those in the PESI
Conclusion
Given the enormous burden of venous thromboembolism in the developed world in terms of public healthcare cost, the identification of very low risk patients eligible for early discharge and outpatient treatment is a very important issue. This priority had not been entirely and successfully addressed by existing risk scores, including PESI and Geneva.
The Low Risk Pulmonary Embolism Decision (LR-PED) score seems more attractive in its ability to identify patients at very low mortality risk who
Conflict of Interest Statement
None.
Acknowledgments
Financial support: none.
Writing assistance: none.
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2014, Clinics in Laboratory MedicineCitation Excerpt :Patients with a low or normal NT-pro-BNP level (<500 pg/mL) have been successfully treated for PE as outpatients.24 Furthermore, the low-risk PE decision rule (Box 4) incorporates clinical assessments and markers of cardiac stress into a formula used to determine 30-day mortality, and it has been demonstrated to be superior to the PESI and Geneva criteria in terms of predictive accuracy.25 Therefore, appropriate use of these tools, with an increased emphasis placed on risk stratification and standardization, may help clinicians determine the most appropriate treatment setting (inpatient vs outpatient) for patients with PE.
Pulmonary embolism in elderly patients: Prognostic impact of the Cumulative Illness Rating Scale (CIRS) on short-term mortality
2014, Thrombosis ResearchCitation Excerpt :Furthermore, the recognition of truly low-risk patients eligible for an early hospital discharge and outpatient treatment may have a considerable impact on healthcare costs. Various risk scores have been developed and tested as means of identifying low-risk subjects, including the PESI [14], the simplified PESI (sPESI) [21], the Hestia criteria [22], the Geneva score [23], the low-risk pulmonary embolism decision rule [24], and the global registry of acute cardiac events (GRACE) risk score [25]. The PESI is the most well-validated model and currently offers the safest approach, especially when combined with additional parameters such as troponin I and N-terminal pro-hormone of brain natriuretic peptide levels, and echocardiographic markers of right-ventricular dysfunction.
Contrast-enhanced multidetector computed tomography: A new prognosticator in acute pulmonary embolism?
2013, Revista Portuguesa de Cardiologia