Ordering CT pulmonary angiography to exclude pulmonary embolism: defense versus evidence in the emergency room

Mycoplasma pneumoniae pneumonia-associated thromboembolism with plastic bronchitis: a series of five case reports and literature review

BACKGROUND

Mycoplasma pneumoniae pneumonia is a common respiratory infection among children. However, the occurrence of thromboembolism with plastic bronchitis in association with Mycoplasma pneumoniae pneumonia is extremely rare. This case series presents five cases of children with Mycoplasma pneumoniae pneumonia who developed thromboembolism and plastic bronchitis. The clinical presentation, diagnostic approach, and management strategies are discussed.

METHODS

A retrospective analysis was conducted on medical records from a pediatric hospital. Patient demographics, clinical features, laboratory findings, imaging results, treatment modalities, and outcomes were collected.

RESULTS

The patients in our case series presented with varying degrees of respiratory distress, cough, and fever. Imaging studies revealed evidence of thromboembolism based on pulmonary artery occlusion. Bronchial casts were observed by bronchoscopy. Laboratory tests demonstrated elevated D-dimer levels and fibrinogen degradation products. All patients received a combination of low molecular weight heparin anticoagulation and supportive care.

CONCLUSION

Thromboembolism with plastic bronchitis associated with Mycoplasma pneumoniae pneumonia is a rare but potentially serious complication in children. Prompt recognition and management are crucial for improving patient outcomes. This case series highlights the diverse clinical presentations, diagnostic challenges, and treatment strategies for this unique clinical entity. Further research is needed to better understand the pathogenesis and optimal management of this condition.

SPECT Ventilation/Perfusion Imaging for Acute Pulmonary Embolism: Meta-analysis of Diagnostic Test Accuracy

RATIONALE AND OBJECTIVES

This study aimed to evaluate the diagnostic accuracies of ventilation/perfusion-single photon emission computed tomography (V/Q-SPECT) imaging modalities for acute pulmonary embolism (PE). These included, in addition to V/Q-SPECT, V/Q-SPECT with low-dose computed tomography (CT; V/Q-SPECT-CT), Q-SPECT with low-dose CT (Q-SPECT-CT), and Q-SPECT.

MATERIALS AND METHODS

PubMed, Embase, CINAHL, and Web of Science databases were searched, and studies included if they studied ≥10 adult participants with acute PE and reported data on the imaging tests' diagnostic performance. Data were meta-analyzed using bivariate random effects regression model.

RESULTS

Data from participants totaling 4146 from 11 V/Q-SPECT studies, 785 from 7 V/Q-SPECT-CT studies, 1196 from 7 Q-SPECT-CT studies, and 728 from five Q-SPECT studies were separately meta-analyzed. The bivariate weighted mean sensitivity and specificity were 0.94 (95% confidence interval [CI]: 0.88-0.97) and 0.95 (95% CI: 0.87-0.98) for V/Q-SPECT, 0.95 (95% CI: 0.88-0.98) and 0.99 (95% CI: 0.92-1.00) for V/Q-SPECT-CT, 0.92 (95% CI: 0.79-0.97) and 0.92 (95% CI: 0.83-0.96) for Q-SPECT-CT, and 0.89 (95% CI: 0.76-0.95) and 0.86 (95% CI: 0.67-0.95) for Q-SPECT studies. The positive and negative likelihood ratios (+LRs and -LRs) were 17.4 (6.9-44.0) and 0.06 (0.03-0.13), 76.7 (11.8-498.0) and 0.06 (0.02-0.13), 11.0 (5.3-22.9) and 0.09 (0.04-0.23), and 6.4 (2.6-15.8) and 0.13 (0.07-0.27) for V/Q-SPECT, V/Q-SPECT-CT, Q-SPECT-CT, and Q-SPECTs, respectively.

CONCLUSION

In the diagnosis of acute PE, this meta-analysis showed that V/Q-SPECT-CT had the highest specificity and +LR. Conversely, Q-SPECT showed the lowest specificity and an unfavorably high -LR.

Temporal Trends in the Use of Computed Tomographic Pulmonary Angiography for Suspected Pulmonary Embolism in the Emergency Department : A Retrospective Analysis

BACKGROUND

Recently, validated clinical decision rules have been developed that avoid unnecessary use of computed tomographic pulmonary angiography (CTPA) in patients with suspected pulmonary embolism (PE) in the emergency department (ED).

OBJECTIVE

To measure any resulting change in CTPA use for suspected PE.

DESIGN

Retrospective analysis.

SETTING

26 European EDs in 6 countries.

PATIENTS

Patients with CTPA performed for suspected PE in the ED during the first 7 days of each odd month between January 2015 and December 2019.

MEASUREMENTS

The primary end points were the CTPAs done for suspected PE in the ED and the number of PEs diagnosed in the ED each year adjusted to an annual census of 100 000 ED visits. Temporal trends were estimated using generalized linear mixed regression models.

RESULTS

8970 CTPAs were included (median age, 63 years; 56% female). Statistically significant temporal trends for more frequent use of CTPA (836 per 100 000 ED visits in 2015 vs. 1112 in 2019; P < 0.001), more diagnosed PEs (138 per 100 000 in 2015 vs. 164 in 2019; P = 0.028), a higher proportion of low-risk PEs (annual percent change [APC], 13.8% [95% CI, 2.6% to 30.1%]) with more ambulatory management (APC, 19.3% [CI, 4.1% to 45.1%]), and a lower proportion of intensive care unit admissions (APC, -8.9% [CI, -17.1% to -0.3%]) were observed.

LIMITATION

Data were limited to 7 days every 2 months.

CONCLUSION

Despite the recent validation of clinical decision rules to limit the use of CTPA, an increase in the CTPA rate along with more diagnosed PEs and especially low-risk PEs were instead observed.

PRIMARY FUNDING SOURCE

None specific for this study.

Assessment of the Utilization of Validated Diagnostic Predictive Tools and D-Dimer in the Evaluation of Pulmonary Embolism: A Single-Center Retrospective Cohort Study from a Public Hospital in New York City

INTRODUCTION

A significant increase in the use of computed tomography with pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism (PE) has been observed in the past twenty years. We aimed to investigate whether the validated diagnostic predictive tools and D-dimers were adequately utilized in a large public hospital in New York City.

METHODS

We conducted a retrospective review of patients who underwent CTPA for the specific indication of ruling out PE over a period of one year. Two independent reviewers, blinded to each other and to the CTPA and D-dimer results, estimated the clinical probability (CP) of PE using Well's score, the YEARS algorithm, and the revised Geneva score. Patients were classified based on the presence or absence of PE in the CTPA.

RESULTS

A total of 917 patients were included in the analysis (median age: 57 years, female: 59%). The clinical probability of PE was considered low by both independent reviewers in 563 (61.4%), 487 (55%), and 184 (20.1%) patients based on Well's score, the YEARS algorithm, and the revised Geneva score, respectively. D-dimer testing was conducted in less than half of the patients who were deemed to have low CP for PE by both independent reviewers. Using a D-dimer cut-off of <500 ng/mL or the age-adjusted cut-off in patients with a low CP of PE would have missed only a small number of mainly subsegmental PE. All three tools, when combined with D-dimer < 500 ng/mL or <age-adjusted cut-off, yielded a NPV of > 95%.

CONCLUSION

All three validated diagnostic predictive tools were found to have significant diagnostic value in ruling out PE when combined with a D-dimer cut-off of <500 ng/mL or the age-adjusted cut-off. Excessive use of CTPA was likely secondary to suboptimal use of diagnostic predictive tools.

CTPA ordering trends in local emergency departments: are they increasing and did they increase as a result of COVID-19?

PURPOSE

Ordering trends for computed tomographic pulmonary angiogram (CTPA) studies by local emergency departments were assessed, along with the impact of the COVID-19 pandemic on these ordering trends and CTPA positivity rates.

METHODS

A retrospective quantitative analysis was performed on all CTPA studies ordered between February 2018 - January 2022 by three local tertiary care emergency rooms to investigate for pulmonary embolism. Data collected from the first two years of the COVID-19 pandemic was compared to the two years prior to the pandemic to assess for significant changes in ordering trends and positivity rates.

RESULTS

The overall number of CTPA studies ordered increased from 534 studies in 2018-2019 to 657 in 2021-2022 and the rate of positive diagnosis of acute pulmonary embolism varied between 15.8% to 19.5% over the four years studied. There was no statistically significant difference in the number of CTPA studies ordered when comparing the first two years of the COVID-19 pandemic to the two years immediately prior; however, the positivity rate was significantly higher during the first two years of the pandemic.

CONCLUSION

Over the studied period from 2018-2022, the overall number of CTPA studies ordered by local emergency departments has increased, in line with literature reports from other locations. There was also a correlation between the onset of the COVID-19 pandemic and CTPA positivity rates, possibly secondary to the prothrombotic nature of this infection or the increase in sedentary lifestyles during lockdown periods.

Comparison of the safety and efficacy of YEARS, PEGeD, 4PEPS or the sole item "PE is the most likely diagnosis" strategies for the diagnosis of pulmonary embolism in the emergency department: post-hoc analysis of two European cohort studies

BACKGROUND

The optimal strategy for the diagnosis of pulmonary embolism (PE) in the emergency department (ED) remains debated. To reduce the need of imaging testing, several rules have been recently validated using an elevated D-dimer threshold.

OBJECTIVE

To validate the safety of different diagnostic strategies and compare the efficacy in terms of chest imaging testing.

DESIGN AND PATIENTS

Post-hoc analysis of individual data of 3330 adult patients without a high clinical probability of PE in the ED followed-up at 3 months in France and Spain (1916 from the PROPER cohort, 1414 from the MODIGLIANI cohort).

EXPOSURE

Four diagnostic strategies with an elevated D-dimer threshold if PE is unlikely. The YEARS combined with Pulmonary Embolism Rule-out Criteria (PERC) the pulmonary embolism graduated D-dimer (PEGeD) combined with PERC and the 4-level pulmonary embolism probability score (4PEPS) rules were assessed. A modified simplified (MODS) rule with a simplified YEARS reduced to the sole item of "Is PE the most likely diagnosis" combined with PERC was also tested.

OUTCOME MEASURE AND ANALYSIS

The primary outcome was the proportion of diagnosed PE or deep venous thrombosis at 3 months in patients in whom PE could have been excluded without chest imaging according to the tested strategy. The safety of a strategy was confirmed if the failure rate was less than 1.85%. The secondary outcome was the use of imaging testing according to each rule.

RESULTS

Among 3330 analyzed patients, 150 (4.5%) had a PE. The number of missed PEs were 25, 29, 30 and 26 for the PERC+YEARS, PERC+PEGeD, 4PEPS and MODS rules respectively, with a failure rate of 0.75% (95% CI 0.51% to 1.10%), 0.87% (0.61% to 1.25%), 0.90% (0.63% to 1.28%) and 0.78% (0.53% to 1.14%) respectively. There was no significant difference in the failure rate between rules. Except for a significant lower use of chest imaging for 4PEPS compared to YEARS (14.9% vs 16.3%, difference -1.4% [95%CI -2.1% to -0.8%]), there was no difference in the proportion of imaging testing.

CONCLUSION

In this post-hoc analysis of patients with suspicion of PE, YEARS and PEGeD combined with PERC, and 4PEPS were safe to exclude PE. The safety of the modified simplified MODS strategy was also confirmed. There was no significant difference of the failure rate between strategies.

Use of Computed Tomography Pulmonary Angiography in Emergency Departments: A Literature Review

Computed tomography pulmonary angiography (CTPA) has become the most widely used technique for diagnosis or exclusion of a pulmonary embolism (PE). It has been suggested that overuse of this imaging type may be prevalent, especially in emergency departments (EDs). The purpose of this literature review was to explore the use of CTPAs in EDs worldwide. A review following PRISMA guidelines was completed, with research published between September 2010 and August 2020 included. Five key topics emerged: use of CTPAs; explanations for overuse; use of D-dimer; variability in ordering practices between clinicians; and strategies to reduce overuse. This review found that CTPAs continue to be overused in EDs, leading to superfluous risks to patients. Published studies identify that while clinical practice guidelines (CPGs) have a strong effect on reducing unnecessary CTPAs with no significantly increased risk of missed diagnosis, the adoption of these tools by ED clinicians has remained low. This literature review highlights the need for further research into why CTPAs continue to be overused within EDs and why clinicians are hesitant to use CPGs in the clinical setting. Moreover, investigations into other potential strategies that may combat the overuse of this diagnostic tool are essential to reduce potential harm.

How defensive medicine is defined in European medical literature: a systematic review

OBJECTIVES

Defensive medicine has originally been defined as motivated by fear of malpractice litigation. However, the term is frequently used in Europe where most countries have a no-fault malpractice system. The objectives of this systematic review were to explore the definition of the term 'defensive medicine' in European original medical literature and to identify the motives stated therein.

DESIGN

Systematic review.

DATA SOURCES

PubMed, Embase and Cochrane, 3 February 2020, with an updated search on 6 March 2021.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, we reviewed all European original peer-reviewed studies fully or partially investigating 'defensive medicine'.

RESULTS

We identified a total of 50 studies. First, we divided these into two categories: the first category consisting of studies defining defensive medicine by using a narrow definition and the second category comprising studies in which defensive medicine was defined using a broad definition. In 23 of the studies(46%), defensive medicine was defined narrowly as: health professionals' deviation from sound medical practice motivated by a wish to reduce exposure to malpractice litigation. In 27 studies (54%), a broad definition was applied adding … or other self-protective motives. These self-protective motives, different from fear of malpractice litigation, were grouped into four categories: fear of patient dissatisfaction, fear of overlooking a severe diagnosis, fear of negative publicity and unconscious defensive medicine. Studies applying the narrow and broad definitions of defensive medicine did not differ regarding publication year, country, medical specialty, research quality or number of citations.

CONCLUSIONS

In European research, the narrow definition of defensive medicine as exclusively motivated by fear of litigation is often broadened to include other self-protective motives. In order to compare results pertaining to defensive medicine across countries, future studies are recommended to specify whether they are using the narrow or broad definition of defensive medicine.

PROSPERO REGISTRATION NUMBER

CRD42020167215.

CT pulmonary angiography appropriateness in a single emergency department: does the use of revised Geneva score matter?

PURPOSE

To assess the percentage of computed tomography pulmonary angiography (CTPA) procedures that could have been avoided by methodical application of the Revised Geneva Score (RGS) coupled with age-adjusted D-dimer cut-offs rather than only clinical judgment in Emergency Department patients with suspected pulmonary embolism (PE).

MATERIAL AND METHODS

Between November 2019 and May 2020, 437 patients with suspected PE based on symptoms and D-dimer test were included in this study. All patients underwent to CTPA. For each patient, we retrospectively calculated the age-adjusted D-dimer cut-offs and the RGS in the original version. Finally, CT images were retrospectively reviewed, and the presence of PE was recorded.

RESULTS

In total, 43 (9.84%) CTPA could have been avoided by use of RGS coupled with age-adjusted D-dimer cut-offs. Prevalence of PE was 14.87%. From the analysis of 43 inappropriate CTPA, 24 (55.81%) of patients did not show any thoracic signs, two (4.65%) of patients had PE, and the remaining patients had alternative thoracic findings.

CONCLUSION

The study showed good prevalence of PE diagnoses in our department using only physician assessment, although 9.84% CTPA could have been avoided by methodical application of RGS coupled with age-adjusted D-dimer cut-offs.

Impact of coronary risk scores on disposition decision in emergency patients with chest pain

BACKGROUND

Coronary risk scores (CRS) including History, Electrocardiogram, Age, Risk Factors, Troponin (HEART) score and Emergency Department Assessment of Chest pain Score (EDACS) can help identify patients at low risk of major adverse cardiac events. In the emergency department (ED), there are wide variations in hospital admission rates among patients with chest pain.

OBJECTIVE

This study aimed to evaluate the impact of CRS on the disposition of patients with symptoms suggestive of acute coronary syndrome in the ED.

METHODS

This retrospective cohort study included 3660 adult patients who presented to the ED with chest pain between January and July in 2019. Study inclusion criteria were age > 18 years and a primary position International Statistical Classification of Diseases and Related Health Problems-10th revision coded diagnosis of angina pectoris (I20.0-I20.9) or chronic ischemic heart disease (I25.0-I25.9) by the treating ED physician. If the treating ED physician completed the electronic structured variables for CRS calculation to assist disposition planning, then the patient would be classified as the CRS group; otherwise, the patient was included in the control group.

RESULTS

Among the 2676 patients, 746 were classified into the CRS group, whereas the other 1930 were classified into the control group. There was no significant difference in sex, age, initial vital signs, and ED length of stay between the two groups. The coronary risk factors were similar between the two groups, except for a higher incidence of smokers in the CRS group (19.6% vs. 16.1%, p = 0.031). Compared with the control group, significantly more patients were discharged (70.1% vs. 64.6%) directly from the ED, while fewer patients who were hospitalized (25.9% vs. 29.7%) or against-advise discharge (AAD) (2.6% vs. 4.0%) in the CRS group. Major adverse cardiac events and mortality at 60 days between the two groups were not significantly different.

CONCLUSIONS

A higher ED discharge rate of the group using CRS may indicate that ED physicians have more confidence in discharging low-risk patients based on CRS.

Physicians' views and experiences of defensive medicine: An international review of empirical research

This study systematically maps empirical research on physicians' views and experiences of hedging-type defensive medicine, which involves providing services (eg, tests, referrals) to reduce perceived legal risks. Such practices drive over-treatment and low value healthcare. Data sources were empirical, English-language publications in health, legal and multi-disciplinary databases. The extraction framework covered: where and when the research was conducted; what methods of data collection were used; who the study participants were; and what were the study aims, main findings in relation to hedging-type defensive practices, and proposed solutions. 79 papers met inclusion criteria. Defensive medicine has mainly been studied in the United States and European countries using quantitative surveys. Surgery and obstetrics have been key fields of investigation. Hedging-type practices were commonly reported, including: ordering unnecessary tests, treatments and referrals; suggesting invasive procedures against professional judgment; ordering hospitalisation or delaying discharge; and excessive documentation in medical records. Defensive practice was often framed around the threat of negligence lawsuits, but studies recognised other legal risks, including patient complaints and regulatory investigations. Potential solutions to defensive medicine were identified at macro (law, policy), meso (organisation, profession) and micro (physician) levels. Areas for future research include qualitative studies to investigate the behavioural drivers of defensive medicine and intervention research to determine policies and practices that work to support clinicians in de-implementing defensive, low-value care.

Feasibility of a quality improvement project to increase adherence to evidence-based pulmonary embolism diagnosis in the emergency department

Background

Many evidence-based clinical decision tools are available for the diagnosis of pulmonary embolism (PE). However, these clinical decision tools have had suboptimal uptake in the everyday clinical practice in emergency departments (EDs), despite numerous implementation efforts. We aimed to test the feasibility of a multi-faceted intervention to implement an evidence-based PE diagnosis protocol.

Methods

We conducted an interrupted time series study in three EDs in Ontario, Canada. We enrolled consecutive adult patients accessing the ED with suspected PE from January 1, 2018, to February 28, 2020. Components of the intervention were as follows: clinical leadership endorsement, a new pathway for PE testing, physician education, personalized confidential physician feedback, and collection of patient outcome information. The intervention was implemented in November 2019. We identified six criteria for defining the feasibility outcome: successful implementation of the intervention in at least two of the three sites, capturing data on ≥ 80% of all CTPAs ordered in the EDs, timely access to electronic data, rapid manual data extraction with feedback preparation before the end of the month ≥ 80% of the time, and time required for manual data extraction and feedback preparation ≤ 2 days per week in total.

Results

The intervention was successfully implemented in two out of three sites. A total of 5094 and 899 patients were tested for PE in the period before and after the intervention, respectively. We captured data from 90% of CTPAs ordered in the EDs, and we accessed the required electronic data. The manual data extraction and individual emergency physician audit and feedback were consistently finalized before the end of each month. The time required for manual data extraction and feedback preparation was ≤ 2 days per week (14 h).

Conclusions

We proved the feasibility of implementing an evidence-based PE diagnosis protocol in two EDs. We were not successful implementing the protocol in the third ED.

Registration

The study was not registered.

Application of human factors to improve usability of clinical decision support for diagnostic decision-making: a scenario-based simulation study

OBJECTIVE

In this study, we used human factors (HF) methods and principles to design a clinical decision support (CDS) that provides cognitive support to the pulmonary embolism (PE) diagnostic decision-making process in the emergency department. We hypothesised that the application of HF methods and principles will produce a more usable CDS that improves PE diagnostic decision-making, in particular decision about appropriate clinical pathway.

MATERIALS AND METHODS

We conducted a scenario-based simulation study to compare a HF-based CDS (the so-called CDS for PE diagnosis (PE-Dx CDS)) with a web-based CDS (MDCalc); 32 emergency physicians performed various tasks using both CDS. PE-Dx integrated HF design principles such as automating information acquisition and analysis, and minimising workload. We assessed all three dimensions of usability using both objective and subjective measures: effectiveness (eg, appropriate decision regarding the PE diagnostic pathway), efficiency (eg, time spent, perceived workload) and satisfaction (perceived usability of CDS).

RESULTS

Emergency physicians made more appropriate diagnostic decisions (94% with PE-Dx; 84% with web-based CDS; p<0.01) and performed experimental tasks faster with the PE-Dx CDS (on average 96 s per scenario with PE-Dx; 117 s with web-based CDS; p<0.001). They also reported lower workload (p<0.001) and higher satisfaction (p<0.001) with PE-Dx.

CONCLUSIONS

This simulation study shows that HF methods and principles can improve usability of CDS and diagnostic decision-making. Aspects of the HF-based CDS that provided cognitive support to emergency physicians and improved diagnostic performance included automation of information acquisition (eg, auto-populating risk scoring algorithms), minimisation of workload and support of decision selection (eg, recommending a clinical pathway). These HF design principles can be applied to the design of other CDS technologies to improve diagnostic safety.

How defensive medicine is defined and understood in European medical literature: protocol for a systematic review

INTRODUCTION

The term defensive medicine, referring to actions motivated primarily by litigious concerns, originates from the USA and has been used in medical research literature since the late 1960s. Differences in medical legal systems between the US and most European countries with no tort legislation raise the question whether the US definition of defensive medicine holds true in Europe.

AIM

To present the protocol of a systematic review investigating variations in definitions and understandings of the term 'defensive medicine' in European research articles.

METHODS AND ANALYSIS

In concordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic review of all medical research literature that investigate defensive medicine will be performed by two independent reviewers. The databases PubMed, Embase and Cochrane will be systematically searched on the basis of predetermined criteria. Data from all included European studies will systematically be extracted including the studies' definitions and understandings of defensive medicine, especially the motives for doing medical actions that the study regards as 'defensive'.

ETHICS AND DISSEMINATION

No ethics clearance is required as no primary data will be collected. The results of the systematic review will be published in a peer-reviewed, international journal.

PROSPERO REGISTRATION NUMBER

This review has been submitted to International Prospective Register of Systematic Reviews (PROSPERO) and is awaiting registration.

Performance of Computed Tomographic Pulmonary Angiography Compared With Standard Chest Computed Tomography for Identification of Solid Organ, Serosal, and Nodal Findings

PURPOSE

Computed tomographic pulmonary angiography (CTPA) is the test of choice for patients with acute chest pain and suspected pulmonary embolism (PE). This examination is excellent for the diagnosis of PE and can also often identify alternative diagnoses. The early phase of contrast, however, may not allow for optimal evaluation of lymph nodes, serosal surfaces, and solid organs, leading to the nonvisualization of important findings and the potential for missed diagnoses. The purpose of this study was to determine the frequency of relevant findings only identified on standard portal venous phase CT compared with CTPA.

MATERIALS AND METHODS

The reports for all patients in the previous 10 years who underwent both standard CT and CTPA within 7 days, for a total of 675 pairs of scans, were tabulated according to the presence of PE, serosal abnormalities, solid organ abnormalities, and lymphadenopathy. All findings were categorized as present on both scans, standard CT only, or CTPA only. The scans were manually evaluated to exclude findings that were new or resolved on the second study or outside the field of view on one of the studies.

RESULTS

Significantly more PEs were identified only on CTPA examinations. However, significantly more pleural, peritoneal, and solid organ abnormalities, and abnormal mediastinal and abdominal lymph nodes were identified on standard CT only. There was no significant difference in the identification of pericardial abnormalities or abnormal hilar lymph nodes between the two scans.

CONCLUSIONS

Many serosal abnormalities, solid organ abnormalities, and lymphadenopathy were only reported on standard portal venous phase CT compared with CTPA.

Assessment of the current D-dimer cutoff point in pulmonary embolism workup at a single institution: Retrospective study

Background:

The currently used D-dimer (DD) cutoff point is associated with a large number of negative CT-pulmonary angiographies (CTPA). We hypothesized presence of deficiency in the current cutoff and a need to look for a better DD threshold.

Materials and Methods:

We conducted a retrospective medical records analysis of all patients who had a CTPA as part of pulmonary embolism (PE) workup over a 1-year period. All emergency room (ER) patients who had DD assay checked prior to CTPA were included in the analysis. We assessed our institutional cutoff point and tried to test other presumptive DD thresholds retrospectively.

Results:

At our institution 1591 CTPA were performed in 2014, with 1220 scans (77%) performed in the ER. DD test was ordered prior to CTPA imaging in 238 ER patients (19.5%) as part of the PE workup. PE was diagnosed in 14 cases (6%). The sensitivity and specificity of the currently used DD cutoff (0.5 mcg/mL) were found to be 100% and 13%, respectively. Shifting the cutoff value from 0.5 to 0.85 mcg/mL would result in a significant increase in the specificity from 13% to 51% while maintaining the same sensitivity of 100%. This would make theoretically 84 CTPA scans, corresponding to 35% of CTPA imaging, unnecessary because DD would be considered negative based on this presumptive threshold.

Conclusions:

Our results suggest a significant deficiency in the institutional DD cutoff point with the need to find a better threshold through a large multicenter prospective trial to minimize unnecessary CTPA scans and to improve patient safety.

Unenhanced multidetector computed tomography findings in acute central pulmonary embolism

Background

Computed tomography pulmonary angiography (CTPA) is the gold standard for the diagnosis of pulmonary embolism (PE). However, contrast is contraindicated in some patients. The purpose of this study was to determine the diagnostic accuracy of unenhanced multidetector CT (MDCT) for diagnosis of central PE using CTPA as the gold standard.

Methods

The records of patients with suspected PE seen between 2010 and 2013 were retrospectively reviewed. Inclusion criteria were an acute, central PE confirmed by CTPA and non-enhanced MDCT before contrast injection. Patients with a PE ruled out by CTPA served as a control group. MDCT findings studied were high-attenuation emboli in pulmonary artery (PA), main PA dilatation > 33.2 mm, and peripheral wedge-shaped consolidation. Receiver operating characteristic (ROC) analysis was used to determine the sensitivity and specificity of unenhanced MDCT to detect PE. Wells score of all patients were calculated using data extracted from medical records prior to imaging analysis.

Results

Thirty-two patients with a PE confirmed by CTPA and 32 with a PE ruled out by CTPA were included. Among the three main MDCT findings, high-attenuation emboli in the PA showed best diagnostic performance (Sensitivity 72.9%; Specificity 100%), followed by main PA dilatation > 33.2 mm (sensitivity 46.9%; specificity 90.6%), and peripheral wedge-shaped consolidation (sensitivity 43.8%; specificity 78.1%). Given any one or more positive findings on unenhanced MDCT, the sensitivity was 96.9% and specificity was 71.9% for a diagnosis of PE in patients. The area under the curve (AUC) of a composite measure of unenhanced MDCT findings (0.909) was significantly higher than that of the Wells score (0.688), indicating unenhanced MDCT was reliable for detecting PE than Wells score.

Conclusions

Unenhanced MDCT is an alternative for the diagnosis of acute central PE when CTPA is not available.

Age-dependent diagnostic accuracy of clinical scoring systems and D-dimer levels in the diagnosis of pulmonary embolism with computed tomography pulmonary angiography (CTPA)

OBJECTIVE

The aim of this study was to compare the age-dependent diagnostic performance of clinical scores and D-dimer testing to identify patients with suspected pulmonary embolism (PE).

METHODS

Consecutive patients with suspected PE referred from the emergency department for computed tomography pulmonary angiography (CTPA) were retrospectively evaluated. Diagnostic scores (classic Wells score (WS), modified WS, simplified WS, revised Geneva score (GS), simplified GS, and YEARS score) were calculated from medical records. Results of D-dimer testing were retrieved from the laboratory database. CTPA was the diagnostic reference standard. Four age groups were analyzed (< 50, 50-64, 65-74, and ≥ 75 years). Statistical analysis used receiver operating characteristics as well as uni- and multivariate analyses with calculation of prediction models. The study was IRB approved.

RESULTS

One thousand consecutive patients were included. Areas under the curve (AUC) and accuracies were superior in patients < 50 years. For the classic WS, the AUC decreased by 11% with the optimal cutoff dropping 1.5 points in patients ≥ 75 years; for D-dimer levels, the optimal cutoff was 900 μg/L higher in both ≥ 65 years groups with a max. decrease of the AUC of 9%. In terms of accuracy, the YEARS score performed best across all groups. Classic WS and D-dimer level showed a significant interaction with patient age in prediction models.

CONCLUSION

D-dimer measurement and clinical scores perform best in patients < 50 years. The YEARS score performs best across all age groups and is therefore recommended.

KEY POINTS

• The probability of pulmonary embolism predicted by fibrin fibrinogen degradation products and clinical scores shows the highest accuracy in patients < 50 years. • The probability of pulmonary embolism predicted by the YEARS score shows the highest accuracy in each age group. • Classic Wells score and fibrin fibrinogen degradation products show a significant interaction with patient age in a logistic regression model.

Interventions to Reduce the Overuse of Imaging for Pulmonary Embolism: A Systematic Review

BACKGROUND

Imaging use in the diagnostic workup of pulmonary embolism (PE) has increased markedly in the last 2 decades. Low PE prevalence and diagnostic yields suggest a significant problem of overuse.

PURPOSE

The purpose of this systematic review is to summarize the evidence associated with the interventions aimed at reducing the overuse of imaging in the diagnostic workup of PE in the emergency department and hospital wards.

DATA SOURCES

PubMed, MEDLINE, Embase, and EBM Reviews from 1998 to March 28, 2017.

STUDY SELECTION

Experimental and observational studies were included. The types of interventions, their efficacy and safety, the impact on healthcare costs, the facilitators, and barriers to their implementation were assessed.

DATA SYNTHESIS

Seventeen studies were included assessing clinical decision support (CDS), educational interventions, performance and feedback reports (PFRs), and institutional policy. CDS impact was most comprehensively documented. It was associated with a reduction in imaging use, ranging from 8.3% to 25.4%, and an increase in diagnostic yield, ranging from 3.4% to 4.4%. The combined implementation of a CDS and PFR resulted in a modest but significant increase in the adherence to guidelines. Few studies appraised the safety of interventions. There was a lack of evidence concerning economic aspects, facilitators, and barriers.

CONCLUSIONS

A combined implementation of an electronic CDS and PFRs is more effective than purely educational or policy interventions, although evidence is limited. Future studies of high-methodological quality would strengthen the evidence concerning their efficacy, safety, facilitators, and barriers.

Qualitative Study to Understand Ordering of CT Angiography to Diagnose Pulmonary Embolism in the Emergency Room Setting

PURPOSE

To better understand the decision making behind the ordering of CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism (PE) in the emergency department.

METHODS

We conducted semistructured interviews with our institution's emergency medicine (EM) providers and radiologists who read CTPAs performed in the emergency department. We employed the Theoretical Domains Framework-a formal, structured approach used to better understand the motivations and beliefs of physicians surrounding a complex medical decision making-to categorize the themes that arose from our interviews.

RESULTS

EM providers were identified as the main drivers of CTPA ordering. Both EM and radiologist groups perceived the radiologist's role as more limited. Experience- and gestalt-based heuristics were the most important factors driving this decision and more important, in many cases, than established algorithms for CTPA ordering. There were contrasting views on the value of d-dimer in the suspected PE workup, with EM providers finding this test less useful than radiologists. EM provider and radiologist suggestions for improving the appropriateness of CTPA ordering consisted of making this process more arduous and incorporating d-dimer tests and prediction rules into a decision support tool.

CONCLUSION

EM providers were the main drivers of CTPA ordering, and there was a marginalized role for the radiologist. Experience- and gestalt-based heuristics were the main influencers of CTPA ordering. Our findings suggest that a more nuanced intervention than simply including a d-dimer and a prediction score in each preimaging workup may be necessary to curb overordering of CTPA in patients suspected of PE.

The Economic Value of Hybrid Single-photon Emission Computed Tomography With Computed Tomography Imaging in Pulmonary Embolism Diagnosis

Objective

The objective was to quantify the potential economic value of single‐photon emission computed tomography (SPECT) with computed tomography (CT; SPECT/CT) versus CT pulmonary angiography (CTPA), ventilation–perfusion (V/Q) planar scintigraphy, and V/Q SPECT imaging modalities for diagnosing suspected pulmonary embolism (PE) patients in an emergency setting.

Methods

An Excel‐based simulation model was developed to compare SPECT/CT versus the alternate scanning technologies from a payer's perspective. Clinical endpoints (diagnosis, treatment, complications, and mortality) and their corresponding cost data (2016 USD) were obtained by performing a best evidence review of the published literature. Studies were pooled and parameters were weighted by sample size. Outcomes measured included differences in 1) excess costs, 2) total costs, and 3) lives lost per annum between SPECT/CT and the other imaging modalities. One‐way (±25%) sensitivity and three scenario analyses were performed to gauge the robustness of the results.

Results

For every 1,000 suspected PE patients undergoing imaging, expected annual economic burden by modality was found to be 3.2 million (SPECT/CT), 3.8 million (CTPA), 5.8 million (planar), and 3.6 million (SPECT) USD, with a switch to SPECT/CT technology yielding per‐patient‐per‐month cost savings of $51.80 (vs. CTPA), $213.80 (vs. planar), and $36.30 (vs. SPECT), respectively. The model calculated that the incremental number of lives saved with SPECT/CT was six (vs. CTPA) and three (vs. planar). Utilizing SPECT/CT as the initial imaging modality for workup of acute PE was also expected to save $994,777 (vs. CTPA), $2,852,014 (vs. planar), and $435,038 (vs. SPECT) in “potentially avoidable”’ excess costs per annum for a payer or health plan.

Conclusion

Compared to the currently available scanning technologies for diagnosing suspected PE, SPECT/CT appears to confer superior economic value, primarily via improved sensitivity and specificity and low nondiagnostic rates. In turn, the improved diagnostic accuracy accords this modality the lowest ratio of expenses attributable to potentially avoidable complications, misdiagnosis, and underdiagnosis.

Self-awareness of computed tomography ordering in the emergency department

OBJECTIVES

Physician variation in the use of computed tomography (CT) is concerning due to the risks of ionizing radiation, cost, and downstream effects of unnecessary testing. The objectives of this study were to describe variation in CT-ordering rates among emergency physicians (EPs), to measure correlation between perceived and actual CT-ordering rates, to assess attitudes that influence decisions to order imaging tests, and to identify EP attitudes associated with higher CT utilization.

METHODS

This study was a retrospective review of imaging and administrative billing records at two emergency department sites of a tertiary care adult teaching hospital. The study also included a cross-sectional survey of EPs at this hospital. We asked physicians about their perceived ordering behaviour, and what factors influenced their decision to order a CT. We examined correlations between perceived and actual CT-ordering rates. We adjusted ordering rates for shift distribution using a logistic regression model and identified outlier physicians whose ordering rate was significantly lower or higher than expected. We used multivariable regression analysis to determine which survey responses predicted higher CT utilization.

RESULTS

During the study period, 59 EPs saw 45,854 patients, and ordered 6,609 CTs - a mean ordering rate of 14.4% (standard deviation (SD)=4.3%). The ordering rate for individual physicians ranged from 5.9% to 25.9%. Of the 59 EPs, 13 EPs were low-ordering outliers; 12 were high-ordering outliers. Forty-five EPs (76.3%) completed the survey. Mean perceived ordering rate was 12.6%, and was weakly correlated with actual ordering (r=0.19, p=0.21). 42 EPs (93.3%) believed they ordered "about the same" or "fewer" CTs than their peers. Of the 17 EPs in the two highest ordering quintiles, only 3 (18%) knew they were high orderers. In the multivariable analysis, higher ordering was associated with increasing strength of response to the following predictors: medico-legal risk (relative risk [RR]=1.18, 95% CI: 1.03-1.21), risk of contrast (RR=1.14, 95% CI: 1.07-1.22), what colleagues would do (RR=1.09, 95% CI: 0.99-1.19), risk of missing a diagnosis (RR=1.08, 95% CI: 0.98-1.21), and patient wishes (RR=1.07, 95% CI: 0.97-1.17).

CONCLUSIONS

There is large variation in CT ordering among EPs. Physicians' self-reported ordering rate correlates poorly with actual ordering. High CT orderers were rarely aware that they ordered more than their colleagues. Higher rates of ordering were observed among physicians who reported increased concern with 1) risk of missing a diagnosis, 2) medico-legal risk, 3) risk of contrast, 4) patient wishes, and 5) what colleagues would do.

Validation of the German version of two scales (RIS, RCS-HCP) for measuring regret associated with providing healthcare

BACKGROUND

The regret intensity scale (RIS) and the regret coping scale for healthcare professionals (RCS-HCP) working in hospitals assess the experience of care-related regrets and how healthcare professional deal with these negative events. The aim of this study was to validate a German version of the RIS and the RCS-HCP.

METHODS

The RIS and RCS-HCP in German were first translated into German (forward- and backward translations) and then pretested with 16 German-speaking healthcare professionals. Finally, two surveys (test and 1-month retest) administered the scales to a large sample of healthcare professionals from two different hospitals.

RESULTS

Of the 2142 eligible healthcare professionals, 494 (23.1%) individuals (108 physicians) completed the cross-sectional web based survey and 244 completed the retest questionnaire. Participants (n = 165, 33.4% of the total sample) who reported not having experienced a regret in the last 5 years, had significantly more days of sick leave during the last 6 months. These participants were excluded from the subsequent analyses. The structure of the scales was similar to the French version with a single dimension for the regret intensity scale (Cronbach's alpha: 0.88) and three types of coping strategies for the regret coping scale (alphas: 0.69 for problem-focused strategies, 0.67 for adaptive strategies and 0.86 for the maladaptive strategies). Construct validity was good and reproduced the findings of the French study, namely that higher regret intensity was associated with situations that entailed more consequences for the patients. Furthermore, higher regret intensity and more frequent use of maladaptive strategies were associated with more sleep difficulties and less work satisfaction.

CONCLUSIONS

The German RIS and RCS-HCP scales were found valid for measuring regret intensity and regret coping in a population of healthcare professionals working in a hospital. Reporting no regret, which corresponds to the coping strategy of suppression, seems to be a maladaptive strategy because it was associated with more frequent sick day leaves.

RESPECT-ED: Rates of Pulmonary Emboli (PE) and Sub-Segmental PE with Modern Computed Tomographic Pulmonary Angiograms in Emergency Departments: A Multi-Center Observational Study Finds Significant Yield Variation, Uncorrelated with Use or Small PE Rates

INTRODUCTION

Overuse of CT Pulmonary Angiograms (CTPA) for diagnosing pulmonary embolism (PE), particularly in Emergency Departments (ED), is considered problematic. Marked variations in positive CTPA rates are reported, with American 4-10% yields driving most concerns. Higher resolution CTPA may increase sub-segmental PE (SSPE) diagnoses, which may be up to 40% false positive. Excessive use and false positives could increase harm vs. benefit. These issues have not been systematically examined outside America.

AIMS

To describe current yield variation and CTPA utilisation in Australasian ED, exploring potential factors correlated with variation.

METHODS

A retrospective multi-centre review of consecutive ED-ordered CTPA using standard radiology reports. ED CTPA report data were inputted onto preformatted data-sheets. The primary outcome was site level yield, analysed both intra-site and against a nominated 15.3% yield. Factors potentially associated with yield were assessed for correlation.

RESULTS

Fourteen radiology departments (15 ED) provided 7077 CTPA data (94% ≥64-slice CT); PE were reported in 1028 (yield 14.6% (95%CI 13.8-15.4%; range 9.3-25.3%; site variation p <0.0001) with four sites significantly below and one above the 15.3% target. Admissions, CTPA usage, PE diagnosis rates and size of PE were uncorrelated with yield. Large PE (≥lobar) were 55% (CI: 52.1-58.2%) and SSPE 8.8% (CI: 7.1-10.5%) of positive scans. CTPA usage (0.2-1.5% adult attendances) was correlated (p<0.006) with PE diagnosis but not SSPE: large PE proportions.

DISCUSSION/ CONCLUSIONS

We found significant intra-site CTPA yield variation within Australasia. Yield was not clearly correlated with CTPA usage or increased small PE rates. Both SSPE and large PE rates were similar to higher yield historical cohorts. CTPA use was considerably below USA 2.5-3% rates. Higher CTPA utilisation was positively correlated with PE diagnoses, but without evidence of increased proportions of small PE. This suggests that increased diagnoses seem to be of clinically relevant sized PE.

An analysis of causative factors in closed criminal medical malpractice cases of the Taiwan Supreme Court: 2000-2014

Most medical malpractice in Taiwan leads to criminal prosecution. This study examined the epidemiologic factors and clinical errors that led to medical malpractice convictions in Taiwanese criminal prosecutions. A retrospective, 15-year population-based review of criminal Supreme Court judgments pertaining to medical malpractice against physicians and nurses was conducted. Eighty-four cases were reviewed, yielding data that included the number and specialty involved, accused hospitals, the diagnosis, the time interval between incidents to closure, result of adjudication, the origin of cases (private vs. public prosecution), the result of medical appraisal, and the primary error. Overall, the cases averaged 7.6years to achieve final adjudication. Seventy-five percent were settled in favor of the clinician; twenty-three physicians and three nurses were found guilty, but all of these avoided imprisonment via probation or replacement with forfeit. The single most risky specialty was emergency medicine (22.6% of the cases), with 36.8% of those resulting in guilty verdicts. The most common diagnosis groups were infectious diseases (23.8%), intracranial hemorrhages (10.7%), and acute coronary syndrome (9.5%). Public prosecutions had a 41.2% conviction rate; no guilty verdicts resulted from private prosecution. Nineteen (22.6%) cases were commuted, and 73.7% of those had a controversial appraisal result. The characteristics of criminal malpractice prosecution in Taiwan that could be improved to relieve the stress of frivolous lawsuits on the judicial process include lengthy jurisdiction process; low public-prosecution conviction rate; frequent commuted jurisdiction related to a controversial appraisal; and zero imprisonment rate for clinicians.

Prospective evaluation of the ability of clinical scoring systems and physician-determined likelihood of appendicitis to obviate the need for CT

OBJECTIVE

To determine whether clinical scoring systems or physician gestalt can obviate the need for computed tomography (CT) in patients with possible appendicitis.

METHODS

Prospective, observational study of patients with abdominal pain at an academic emergency department (ED) from February 2012 to February 2014. Patients over 11 years old who had a CT ordered for possible appendicitis were eligible. All parameters needed to calculate the scores were recorded on standardised forms prior to CT. Physicians also estimated the likelihood of appendicitis. Test characteristics were calculated using clinical follow-up as the reference standard. Receiver operating characteristic curves were drawn.

RESULTS

Of the 287 patients (mean age (range), 31 (12-88) years; 60% women), the prevalence of appendicitis was 33%. The Alvarado score had a positive likelihood ratio (LR(+)) (95% CI) of 2.2 (1.7 to 3) and a negative likelihood ratio (LR(-)) of 0.6 (0.4 to 0.7). The modified Alvarado score (MAS) had LR(+) 2.4 (1.6 to 3.4) and LR(-) 0.7 (0.6 to 0.8). The Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA) score had LR(+) 1.3 (1.1 to 1.5) and LR(-) 0.5 (0.4 to 0.8). Physician-determined likelihood of appendicitis had LR(+) 1.3 (1.2 to 1.5) and LR(-) 0.3 (0.2 to 0.6). When combined with physician likelihoods, LR(+) and LR(-) was 3.67 and 0.48 (Alvarado), 2.33 and 0.45 (RIPASA), and 3.87 and 0.47 (MAS). The area under the curve was highest for physician-determined likelihood (0.72), but was not statistically significantly different from the clinical scores (RIPASA 0.67, Alvarado 0.72, MAS 0.7).

CONCLUSIONS

Clinical scoring systems performed equally well as physician gestalt in predicting appendicitis. These scores do not obviate the need for imaging for possible appendicitis when a physician deems it necessary.

Evaluation of Patients With Suspected Acute Pulmonary Embolism: Best Practice Advice From the Clinical Guidelines Committee of the American College of Physicians

DESCRIPTION

Pulmonary embolism (PE) can be a severe disease and is difficult to diagnose, given its nonspecific signs and symptoms. Because of this, testing patients with suspected acute PE has increased dramatically. However, the overuse of some tests, particularly computed tomography (CT) and plasma d-dimer measurement, may not improve care while potentially leading to patient harm and unnecessary expense.

METHODS

The literature search encompassed studies indexed by MEDLINE (1966-2014; English-language only) and included all clinical trials and meta-analyses on diagnostic strategies, decision rules, laboratory tests, and imaging studies for the diagnosis of PE. This document is not based on a formal systematic review, but instead seeks to provide practical advice based on the best available evidence and recent guidelines. The target audience for this paper is all clinicians; the target patient population is all adults, both inpatient and outpatient, suspected of having acute PE.

BEST PRACTICE ADVICE 1

Clinicians should use validated clinical prediction rules to estimate pretest probability in patients in whom acute PE is being considered.

BEST PRACTICE ADVICE 2

Clinicians should not obtain d-dimer measurements or imaging studies in patients with a low pretest probability of PE and who meet all Pulmonary Embolism Rule-Out Criteria.

BEST PRACTICE ADVICE 3

Clinicians should obtain a high-sensitivity d-dimer measurement as the initial diagnostic test in patients who have an intermediate pretest probability of PE or in patients with low pretest probability of PE who do not meet all Pulmonary Embolism Rule-Out Criteria. Clinicians should not use imaging studies as the initial test in patients who have a low or intermediate pretest probability of PE.

BEST PRACTICE ADVICE 4

Clinicians should use age-adjusted d-dimer thresholds (age × 10 ng/mL rather than a generic 500 ng/mL) in patients older than 50 years to determine whether imaging is warranted.

BEST PRACTICE ADVICE 5

Clinicians should not obtain any imaging studies in patients with a d-dimer level below the age-adjusted cutoff.

BEST PRACTICE ADVICE 6

Clinicians should obtain imaging with CT pulmonary angiography (CTPA) in patients with high pretest probability of PE. Clinicians should reserve ventilation-perfusion scans for patients who have a contraindication to CTPA or if CTPA is not available. Clinicians should not obtain a d-dimer measurement in patients with a high pretest probability of PE.

A conceptual model of emergency physician decision making for head computed tomography in mild head injury

The use of computed tomographic scanning in blunt head trauma has increased dramatically in recent years without an accompanying rise in the prevalence of injury or hospital admission for serious conditions. Because computed tomography is neither harmless nor inexpensive, researchers have attempted to optimize utilization, largely through research that describes which clinical variables predict intracranial injury, and use this information to develop clinical decision instruments. Although such techniques may be useful when the benefits and harms of each strategy (neuroimaging vs observation) are quantifiable and amenable to comparison, the exact magnitude of these benefits and harms remains unknown in this clinical scenario. We believe that most clinical decision instrument development efforts are misguided insofar as they ignore critical, nonclinical factors influencing the decision to image. In this article, we propose a conceptual model to illustrate how clinical and nonclinical factors influence emergency physicians making this decision. We posit that elements unrelated to standard clinical factors, such as personality of the physician, fear of litigation and of missed diagnoses, patient expectations, and compensation method, may have equal or greater impact on actual decision making than traditional clinical factors. We believe that 3 particular factors deserve special consideration for further research: fear of error/malpractice, financial incentives, and patient engagement. Acknowledgement and study of these factors will be essential if we are to understand how emergency physicians truly make these decisions and how test-ordering behavior can be modified.

Medical emergencies: pulmonary embolism and acute severe asthma

In this, the second of two articles covering specific medical emergencies, we discuss the definitions, epidemiology, pathophysiology, acute and chronic management of pulmonary embolus and acute severe asthma.

Acute cardiac disorder or pneumonia and concomitant presence of pulmonary embolism

Purpose

To determine the frequency of apparent acute pulmonary embolism (PE) and of concomitant disease in computed tomography pulmonary angiography (CTPA); to compare the frequency of PE in patients with pneumonia or acute cardiac disorder (acute coronary syndrome, tachyarrhythmia, acute left ventricular heart failure or cardiogenic shock), with the frequency of PE in patients with none of these alternative chest pathologies (comparison group).

Methods

Retrospective analysis of all patients who received a CTPA at the emergency department (ED) within a period of four years and 5 months.

Results

Of 1275 patients with CTPA, 28 (2.2%) had PE and concomitant radiologic evidence of another chest disease; 3 more (0.2%) had PE and an acute cardiac disorder without radiological evidence of heart failure. PE was found in 11 of 113 patients (10%) with pneumonia, in 5 of 154 patients (3.3%) with an acute cardiac disorder and in 186 of 1008 patients (18%) in the comparison group. After adjustment for risk factors for thromboembolism and for other relevant patient’s characteristics, the proportion of CTPAs with evidence of PE in patients with an acute cardiac disorder or pneumonia was significantly lower than in the comparison group (OR 0.13, 95% CI 0.05–0.33, p<0.001 for patients with an acute cardiac disorder, and OR 0.45, 95% CI 0.23–0.89, p = 0.021 for patients with pneumonia).

Conclusion

The frequency of PE and a concomitant disease that can mimic PE was low. The presence of an acute cardiac disorder or pneumonia was associated with decreased odds of PE.