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    Simplified PESI (Pulmonary Embolism Severity Index)

    Predicts 30-day outcome of patients with PE, with fewer criteria than the original PESI.
    When to Use
    Why Use

    In the setting of a patient diagnosed with pulmonary embolism, the sPESI can be utilized to determine if he/she is a possible candidate for outpatient management. For those determined to be low risk (score of 0), mortality risk is 1.1%.

    The Simplified Pulmonary Embolism Severity Index (sPESI) was designed to remove some of the more complicated elements of the Pulmonary Embolism Severity Index (PESI) and aid in the risk stratification of patients with pulmonary embolism (PE).

    • The sPESI is easier to remember and simpler to use than its predecessor.
    • The sPESI has been shown to be equally as accurate as, if not more than, the original PESI.
    • The sPESI is a rule-out type of tool. ALL criteria must be answered “no” in order for the patient to be considered low-risk.
    • The sPESI is meant to aid in decision making, not replace it. Clinical judgement should always take precedence.
    • Patients determined to be low risk can be considered for outpatient management if clinical and social factors warrant it.

    About the PESI:

    The Pulmonary Embolism Severity Index (PESI) is a risk stratification tool that has been externally validated to determine the mortality and outcome of patients with newly diagnosed pulmonary embolism (PE).

    In the setting of a patient with renal failure or severe comorbidities, clinical judgement should be used over the PESI, as these patients were excluded in the validation study.

    • The PESI score determines risk of mortality and severity of complications.
    • The score does not require laboratory variables.
    • It is meant to aid in decision making, not replace it. Clinical judgement should always take precedence.
    • The PESI score determines clinical severity and can influence treatment setting for management of PE.
      • Class I and II patients may possibly be safely treated as outpatients in the right clinical setting.

    The sPESI is a simpler version of the PESI that is easy to apply to patients who have been diagnosed with PE. In the derivation study it had a better negative predictive value than the PESI. It is simpler to use and comparable in accuracy.


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    • Social situation should be taken into account before considering outpatient management (including the appropriate administration of anticoagulants).
    • Fewer patients were classified as low risk by sPESI than PESI, and the sPESI derivation cohort had patients with more comorbidities than the original.
    • Given low mortality of low risk PE, outpatient management would save significant funds over hospitalization (cited as $4,500 per avoided admission).


    • If the patient is considered low risk (score of 0) by the sPESI:
      • Patient has an overall low risk of mortality (1.1%) or severe morbidity (1.5%).
      • Consider outpatient management of PE if clinically appropriate and social factors allow for it.
    • If the patient is considered high risk (score of ≥ 1) by the sPESI:
      • Patient has an overall high risk of mortality (8.9%) or severe morbidity (2.7%).
      • Consider inpatient management and higher levels of care if clinically appropriate.

    Critical Actions

    • The sPESI is only meant for risk stratification of pulmonary embolism after the diagnosis has been made.
    • The sPESI can not be used to risk stratify patients who are not being treated for PE.
    • Additional pathology which could lead to morbidity or mortality should not be overlooked in the setting of low risk sPESI scores.


    Selection of appropriate criteria - if ≥1 criteria are met, the patient is considered high risk.

    Facts & Figures

    From the derivation study:

    “This study shows that the simplified PESI successfully predicts 30-day mortality after acute symptomatic PE. Compared with the original PESI, the simplified PESI has similar prognostic accuracy. The simplified score had good discrimination and calibration, and an external data set validated the generalizability of its predictive accuracy.”

    Note: While the Simplified PESI was applied to a group of patients with data that was collected prospectively, the rule itself has not been validated in a newly-prospective cohort.

    Evidence Appraisal

    In the Derivation study 995 patients diagnosed in the emergency department in Madrid, Spain, from 2003-2008 were included. PE was confirmed on V/Q, DVT ultrasound or helical CT.

    • In order to simplify the original PESI which had 11 criteria of varying point values:
      1. Age was dichotomized to less than or over 80 years old.
      2. Heart failure and chronic lung disease were combined.
      3. Sex, respiratory rate, temperature and mental status were shown to have low significance to 30-day mortality and removed.
      4. All remaining variables were assigned a point value of 1.
    • Final variables: age >80, history of cancer, history of chronic cardiopulmonary disease, HR ≥ 110, SBP < 100 and O2 SAT <90%.
    • Patients with a score of 0 were determined to be low risk, while those with a score of 1 or more were considered high risk. Points were NOT additive for risk (i.e., mortality was 8.9% in the high risk group whether there was 1 point or 6 points). Each patient was also assigned an original PESI score.
    • Patients were admitted and given LMWH and transitioned to oral vitamin K antagonists. Some were given thrombolytics if hemodynamically unstable.
    • Of the 995 patients in the derivation, 78 (7.8%) died within 30 days.
    • Mortality in the sPESI low risk group was 1.0%, while mortality in the low risk PESI (class I or II) was 2.5%. 3 patients (1.0%) who were classified as low risk sPESI had recurrent nonfatal PE or bleeding.
    • The sPESI classified fewer patients as low risk (30.7%) than the original PESI score (36.3%) in the derivation cohort. The sPESI had a negative predictive value of 99% in the derivation cohort while the PESI had 97.5%, however CI's for these (97.9-100% and 95.9-99.1%) overlapped.
    • In the sPESI cohort, which had older and more male patients than the original PESI study from 2005, also had patients who had a higher risk of cancer and hypoxemia.
    • External validation was performed on 7,106 outpatients enrolled in an international, multi-center observational registry (RIETE). PESI vs. sPESI was compared with 30-day all-cause mortality. 434 (6.1%) overall died within 30 days.
    • 2,569 (36.2%) of the RIETE validation cohort were considered low risk by sPESI and 30-day mortality was 1.1%. 38 (1.5%) of the low risk group had a nonfatal recurrent PE or nonfatal bleeding, while 2.7% of the high risk group had these outcomes.
    • In the validation, the sPESI had a negative predictive value of 98.9%.

    A Meta-analysis from 2012 compared 21 studies from Germany, Spain, Poland, Greece, Switzerland, Belgium, Italy, Greece, the UK, Israel, Korea and the USA. These included 50,021 patients including 4,991 with all-cause death. Pooled all-cause mortality was 2.0% in low risk PESI vs. 16.7% in high risk PESI. Pooled all-cause mortality was 1.8% for low risk sPESI and 25.2% for high risk sPESI.

    • Area Under the Curve (AUC) value was 0.78 for all-cause mortality and 0.82 for PE-related mortality.
    • For all-cause mortality, the PESI subgroup had a pooled sensitivity of 0.9 and specificity of 0.411. The sPESI subgroup had a pooled sensitivity of 0.919 and a specificity of 0.382.
    • For PE mortality, the PESI group had pooled sensitivity of 0.949 and a specificity of 0.382. The sPESI subgroup had a pooled sensitivity of 0.960 and a pooled specificity of 0.365.
    • For adverse outcomes, the PESI subgroup had a pooled sensitivity of 0.826 and a specificity of 0.415. The sPESI subgroup had a pooled sensitivity of 0.816 and a specificity of 0.366.
    • AUC for the sPESI for all-cause mortality, PE mortality and serious events was similar to PESI subgroup.
    Dr. David Jiménez

    About the Creator

    David Jiménez, MD, is associate professor at the University of Alcalá de Henares, Madrid and chief of the Venous Thromboembolism Program at the Ramón y Cajal Hospital in Madrid. He is also president-elect of the Vascular Sections of both the Spanish Society of Respiratory Medicine (SEPAR) and the Madrid Society of Respiratory Medicine (NEUMOMADRID). Dr. Jiménez's research interests include venous thromboembolism, pleural diseases and malignant mesothelioma.

    To view Dr. David Jiménez's publications, visit PubMed

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    About the Creator
    Dr. David Jiménez
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