A structured clinical model for predicting the probability of pulmonary embolism

doi:10.1016/S0002-9343(02)01478-X

The American Journal of Medicine

Volume 114, Issue 3, 15 February 2003, Pages 173-179

https://doi.org/10.1016/S0002-9343(02)01478-X Get rights and content

Abstract

Purpose

To develop a structured model to predict the clinical probability of pulmonary embolism.

Methods

We studied 1100 consecutive patients with suspected pulmonary embolism in whom a definite diagnosis had been established. We used logistic regression analysis to estimate the probability of pulmonary embolism based on patients’ clinical characteristics; the probability was categorized as low (≤10%), intermediate (>10%, ≤50%), moderately high (>50%, ≤90%), or high (>90%).

Results

The overall prevalence of pulmonary embolism was 40% (n = 440). Ten characteristics were associated with an increased risk of pulmonary embolism (male sex, older age, history of thrombophlebitis, sudden-onset dyspnea, chest pain, hemoptysis, electrocardiographic signs of acute right ventricular overload, radiographic signs of oligemia, amputation of the hilar artery, and pulmonary consolidation suggestive of infarction), and five were associated with a decreased risk (prior cardiovascular or pulmonary disease, high fever, pulmonary consolidation other than infarction, and pulmonary edema on the chest radiograph). With this model, 432 patients (39%) were rated a low probability, of whom 19 (4%) had pulmonary embolism; 283 (26%) were rated an intermediate probability, of whom 62 (22%) had pulmonary embolism; 72 (7%) were rated a moderately high probability, of whom 53 (74%) had pulmonary embolism; and 313 (28%) were rated a high probability, of whom 306 (98%) had pulmonary embolism.

Conclusion

This prediction model may be useful for estimating the probability of pulmonary embolism before obtaining definitive test results.

Section snippets

Sample

The sample consisted of 1100 consecutive patients who were referred to our institution for suspected pulmonary embolism between November 1, 1991, and December 31, 1999, and in whom the disease was diagnosed or excluded. The clinical characteristics of 500 of these patients have been described (8). All patients were examined according to a standardized protocol that included clinical evaluation, perfusion lung scanning, and pulmonary angiography 5, 8.

Clinical evaluation

Upon study entry, patients were examined by

Results

The 1100 patients had a median age of 68 years (range, 15 to 94 years); 498 (45%) of them were male (Table 1). Eighty-one percent (n = 891) were hospitalized at the time of study entry. The median time between onset of symptoms and study entry was 1 day (range, 0 to 30 days). Based on angiography and autopsy data, the prevalence of pulmonary embolism was 40% (n = 440). Among patients without pulmonary embolism, 242 had the diagnosis excluded based on a normal or near-normal perfusion scan.

Discussion

The results of large-scale prospective studies of the diagnosis of pulmonary embolism lend support to the concept that clinical assessment is a fundamental step in the diagnostic work-up of patients 4, 5, 6. Although the diagnostic yield of individual signs, symptoms, and common laboratory tests is limited, the combination of these variables, either by empirical assessment or by a prediction rule, can be used to express the clinical probability of pulmonary embolism.

In a multicenter Canadian

Acknowledgements

The authors wish to thank the following physicians who took part in the study: Renato Prediletto, Bruno Formichi, Giorgio Di Ricco, Carlo Marini, Massimo Pistolesi, Germana Allescia, Lucia Tonelli, Carolina Bauleo, Laura Carrozzi, Giosuè Catapano, Luigi Rizzello, Alba Dainelli, and Elvio Scoscia.

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Family history of venous thromboembolism predicts the diagnosis of acute pulmonary embolism in the emergency department
2018, American Journal of Emergency Medicine
Pulmonary embolism (PE) clinical decision rules do not consider a patient's family history of venous thromboembolism (VTE). We evaluated whether a family history of VTE predicts acute PE in the emergency department (ED).
Over a 5.5-year study period, we enrolled a prospective convenience sample of patients presenting to an academic emergency department with chest pain and/or shortness of breath. We defined a family history of VTE as a first-degree relative with previous PE or deep vein thrombosis (DVT). We noted outcomes of testing during the patient's ED stay, including the diagnosis of acute PE by either computed tomography (CT) or ventilation/perfusion (VQ) scan.
Of the 3024 study patients, 19.4% reported a family history of VTE and 1.9% were diagnosed with an acute PE during the ED visit. Patients with a family history of VTE were more likely to be diagnosed with a PE: 3.2% vs. 1.6% (p = 0.009). 82.3% of patients were Pulmonary Embolism Rule-out Criteria (PERC) positive, and among PERC-positive patients, those with a family history of VTE were more likely to be diagnosed with a PE: 3.6% vs. 1.9% (p = 0.016). Of patients who underwent testing for PE (33.7%), patients with a family history of VTE were more likely to be diagnosed with a PE: 9.4% vs. 4.9% (p = 0.032).
Patients with a self-reported family history of VTE in a first-degree relative are more likely to be diagnosed with an acute PE in the ED, even among those patients considered to have a higher likelihood of PE.
A Clinically Meaningful Interpretation of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II and III Data
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This study aimed to calculate the multiple-level likelihood ratios (LRs) and posttest probabilities for a positive, indeterminate, or negative test result for multidetector computed tomography pulmonary angiography (MDCTPA) ± computed tomography venography (CTV) and magnetic resonance pulmonary angiography (MRPA) ± magnetic resonance venography (MRV) for each clinical probability level (two-, three-, and four-level) for the nine most commonly used clinical prediction rules (CPRs) (Wells, Geneva, Miniati, and Charlotte). The study design is a review of observational studies with critical review of multiple cohort studies. The settings are acute care, emergency room care, and ambulatory care (inpatients and outpatients).
Data were used to estimate pulmonary embolism (PE) pretest probability for each of the most commonly used CPRs at each probability level. Multiple-level LRs (positive, indeterminate, negative test) were generated and used to calculate posttest probabilities for MDCTPA, MDCTPA + CTV, MRPA, and MRPA + MRV from sensitivity and specificity results from Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II and PIOPED III for each clinical probability level for each CPR. Nomograms were also created.
The LRs for a positive test result were higher for MRPA compared to MDCTPA without venography (76 vs 20) and with venography (42 vs 18). LRs for a negative test result were lower for MDCTPA compared to MRPA without venography (0.18 vs 0.22) and with venography (0.12 vs 0.15). In the three-level Wells score, the pretest clinical probability of PE for a low, moderate, and high clinical probability score is 5.7, 23, and 49. The posttest probability for an initially low clinical probability PE for a positive, indeterminate, and negative test result, respectively, for MDCTPA is 54, 5 and 1; for MDCTPA + CTV is 52, 2, and 0.7; for MRPA is 82, 6, and 1; and for MRPA + MRV is 72, 3, and 1; for an initially moderate clinical probability PE for MDCTPA is 86, 22, and 5; for MDCTPA + CTV is 85, 10, and 4; for MRPA is 96, 25, and 6; and for MRPA + MRV is 93, 14, and 4; and for an initially high clinical probability of PE for MDCTPA is 95, 47, and 15; for MDCTPA + CTV is 95, 27, and 10; for MRPA is 99, 52, and 17; and for MRPA + MRV is 98, 34, and 13.
For a positive test result, LRs were considerably higher for MRPA compared to MDCTPA. However, both a positive MRPA and MDCTPA have LRs >10 and therefore can confirm the presence of PE. Performing venography reduced the LR for a positive and negative test for both MDCTPA and MRPA. The nomograms give posttest probabilities for a positive, indeterminate, or negative test result for MDCTPA and MRPA (with and without venography) for each clinical probability level for each of the CPR.
Clinical decision support increases diagnostic yield of computed tomography for suspected pulmonary embolism
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Determine effects of evidence-based clinical decision support (CDS) on the use and yield of computed tomographic pulmonary angiography for suspected pulmonary embolism (CTPE) in Emergency Department (ED) patients.
This multi-site prospective quality improvement intervention conducted in three urban EDs used a pre/post design. For ED patients aged 18 + years with suspected PE, CTPE use and yield were compared 19 months pre- and 32 months post-implementation of CDS intervention based on the Wells criteria, provided at the time of CTPE order, deployed in April 2012. Primary outcome was the yield (percentage of studies positive for acute PE). Secondary outcome was utilization (number of studies/100 ED visits) of CTPE. Chi-square and statistical process control chart assessed pre- and post-intervention differences. An interrupted time series analysis was also performed.
Of 558,795 patients presenting October 2010–December 2014, 7987 (1.4%) underwent CTPE (mean age 52 ± 17.5 years, 66% female, 60.1% black); 34.7% of patients presented pre- and 65.3% post-CDS implementation. Overall CTPE diagnostic yield was 9.8% (779/7987 studies positive for PE). Yield increased a relative 30.8% after CDS implementation (8.1% vs. 10.6%; p = 0.0003). There was no statistically significant change in CTPE utilization (1.4% pre- vs. 1.4% post-implementation; p = 0.25). A statistical process control chart demonstrated immediate and sustained improvement in CTPE yield post-implementation. Interrupted time series analysis demonstrated the slope of PE findings versus time to be unchanged before and after the intervention (p = 0.9). However, there was a trend that the intervention was associated with a 50% increased probability of PE finding (p = 0.08), suggesting an immediate rather than gradual change after the intervention.
Implementing evidence-based CDS in the ED was associated with an immediate, significant and sustained increase in CTPE yield without a measurable decrease in CTPE utilization. Further studies will be needed to assess whether stronger interventions could further improve appropriate use of CTPE.
A Clinically Meaningful Interpretation of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) Scintigraphic Data
2017, Academic Radiology
Pulmonary embolism (PE) is a common condition associated with significant morbidity and mortality. Diagnostic test characteristics reported in terms of sensitivity and specificity are difficult to translate at the clinical level. More relevant measures are likelihood ratios (LRs), which can convert a pretest into a posttest probability. The aim of our study was to calculate the LRs and posttest probabilities for multiple-level test result for ventilation/perfusion (V/Q) lung scintigraphy and for perfusion scintigraphy combined with chest radiography using modified Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II and the Prospective Investigative Study of Pulmonary Embolism Diagnosis (PISAPED) criteria for each clinical probability level for the most commonly used clinical prediction rules (CPR) using the PIOPED data.
PE pretest probability was estimated for the most commonly used CPRs (Wells, Geneva, Miniati, and Charlotte) at each clinical probability level (two-, three-, and four-level). Multiple-level LRs (high, indeterminate, low, very low probability, and normal) and the positive, indeterminate, and negative results for V/Q scintigraphy, and the positive, indeterminate, and negative results for perfusion scintigraphy were generated and used to calculate posttest probabilities based on the sensitivity and specificity data from PIOPED for each clinical probability level (low, intermediate, and high) for each CPR. Nomograms were also created.
The LRs for a positive V/Q and perfusion scintigraphy test using modified PIOPED II and PISAPED criteria were 20.6, 11, and 23.7, and for a negative test result were 0.15, 0.16, and 0.2, respectively. In the three-level Wells score, the posttest probability for an initial low clinical probability PE for a positive, indeterminate, and negative test result, respectively, for V/Q scintigraphy is 56, 5, and 0.9; for perfusion scintigraphy with modified PIOPED 40, 7, and 0.9, and with PISAPED 59, not available (N/A), and 1.2; for an initial moderate clinical probability PE for V/Q scintigraphy 86, .22, and 4; for perfusion scintigraphy with modified PIOPED 77, 26, and 5, and with PISAPED 88, N/A, and 6; for an initial high clinical probability of PE for V/Q scintigraphy 95, 48, and 13; and for perfusion scintigraphy with modified PIOPED 92, 53, and 13, and with PISAPED 96, N/A, and 16.
With LRs >10, a positive test result for V/Q and perfusion scintigraphy can confirm the presence of PE. Only a normal test result has low enough LR to exclude PE.
Pulmonary Thromboembolism
2015, Murray and Nadel's Textbook of Respiratory Medicine: Volume 1,2, Sixth Edition
Performance of the Wells score in patients with suspected pulmonary embolism during hospitalization: A delayed-type cross sectional study in a community hospital
2014, Thrombosis Research
The role of the Wells score for patients who develop signs and symptoms of pulmonary embolism (PE) during hospitalization has not been sufficiently validated. The aim of this study is to evaluate the performance of the Wells score for inpatients with suspected PE and to evaluate the prevalence of pulmonary embolism.
We conducted a cross sectional study nested in the prospective Institutional Registry of Thromboembolic Disease at Hospital Italiano de Buenos Aires from June 2006 to March 2011. We included patients who developed symptoms of pulmonary embolism during hospitalization. Patients were stratified based on the Wells score as PE likely (> 4 points) or PE unlikely (≤ 4 points). The presence of pulmonary embolism was defined by pre-specified criteria.
Six hundred and thirteen patients met the inclusion criteria, with an overall prevalence of PE of 36%. Two hundred and nineteen (34%) were classified as PE likely and 394 (66%) as PE unlikely with a prevalence of PE of 66% and 20%, respectively. The Wells score showed a sensitivity of 65 (95% CI 59-72), specificity 81 (95% CI 77-85), positive predictive value 66 (95% CI 60-72) and negative predictive value 80 (95% CI 77-84).
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^☆: This work was supported in part by the Ministry of Health and the Ministry of University and Scientific and Technological Research of Italy.

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Clinical studyA structured clinical model for predicting the probability of pulmonary embolism☆

Abstract

Purpose

Methods

Results

Conclusion

Section snippets

Sample

Clinical evaluation

Results

Discussion

Acknowledgements

Venous thromboembolism

Am Rev Respir Dis

The clinical features of submassive and massive pulmonary emboli

Am J Med

History and physical examination in acute pulmonary embolism in patients without pre-existing cardiac or pulmonary disease

Am J Cardiol

Value of the ventilation-perfusion scan in acute pulmonary embolismresults of the Prospective Investigation Of Pulmonary Embolism Diagnosis (PIOPED)

JAMA

Value of perfusion lung scan in the diagnosis of pulmonary embolismresults of the Prospective Investigative Study of Acute Pulmonary Embolism Diagnosis (PISA-PED)

Am J Respir Crit Care Med

Non-invasive diagnosis of venous thromboembolism in outpatients

Lancet

Use of a clinical model for safe management of patients with suspected pulmonary embolism

Ann Intern Med

Accuracy of clinical assessment in the diagnosis of pulmonary embolism

Am J Respir Crit Care Med

Assessing clinical probability of pulmonary embolism in the emergency ward. A simple score

Arch Intern Med

The electrocardiogram in acute pulmonary embolism

Prog Cardiovasc Dis

Clinical study
A structured clinical model for predicting the probability of pulmonary embolism☆