The use of clinical decision rules for pulmonary embolism in the emergency department: a retrospective study

Trends in CT pulmonary angiography utilization and recurrent imaging in sickle cell disease: a longitudinal study

BACKGROUND

Sickle cell disease (SCD) is a common inherited hemoglobinopathy associated with vaso-occlusive events that can mimic pulmonary embolism (PE), leading to the frequent use of computed tomography pulmonary angiography (CTPA). However, trends in CTPA utilization over time remain unclear. This study aims to evaluate temporal trends and recurrent imaging patterns.

METHODS

A retrospective cohort study was conducted at Salmaniya Medical Complex, Bahrain, including SCD patients who underwent CTPA for suspected PE between April 15, 2013, and April 15, 2024. Descriptive statistics were used to report the frequency of recurrent scans, whereas linear regression analysis was employed to assess trends in CTPA utilization over the study period.

RESULTS

The study included 1,084 patients (median age: 35 years, 55.7% male) with SCD who underwent a total of 1,934 CTPA scans. CTPA utilization remained stable from 2014 to 2020, averaging 10.0-13.6 scans per month. However, a significant surge was observed post-2020, coinciding with the COVID-19 pandemic, peaking in 2023, with an average of 31.3 scans per month, indicating a 2.9-fold increase (p = 0.03). During the study period, 415 patients (38.3%) underwent recurrent CTPA scans, with one-third (32.5%, n = 276) of these scans occurring within a 6-month interval. Although the PE positivity rate was lower in recurrent scans than in initial scans, the difference was not statistically significant (8.8% vs. 10.5%; p = 0.22).

CONCLUSIONS

CTPA utilization among SCD patients remained stable for several years but increased significantly after 2020, coinciding with the COVID-19 pandemic. A substantial proportion of scans were recurrent, with many occurring within a short interval. Moving forward, efforts should focus on mitigating radiation exposure through low-dose protocols and investigating potential factors contributing to the recent increase in scan utilization.

Influence of an Alternative Diagnosis on the Diagnosis of Pulmonary Thromboembolism

BACKGROUND

The diagnosis of pulmonary embolism (PE) is based on the application of a priori probability scales such as the Wells scale or PERC. However, the clinical heterogeneity of this pathology results in the absence of a target population to apply these algorithms. The Wells score does consider the possibility of an alternative diagnosis, awarding an additional point if no other diagnosis is likely, yet the presence of objective alternative diagnoses can still complicate clinical assessment and lead to unnecessary testing or missed diagnoses.

OBJECTIVE

The aim of this study is to evaluate the discrimination capacity of clinical objective factors with a high negative predictive value for PE, compared to PERC in terms of reducing unnecessary testing across different risk strata of the Wells scale.

MATERIALS AND METHODS

This was a single-center retrospective cohort study, including patients who underwent chest CT angiography to rule out PE at a university hospital between 2008 and 2017, considering the presence of PE as the study outcome. The study collected demographic data, comorbidities, and clinical presentation data. The presence of objective criteria for pneumonia, heart failure, exacerbation of COPD, or the use of anticoagulation in non-oncological patients were considered a priori criteria with a high negative predictive value.

RESULTS

The analyses were performed on a cohort of 399 patients with an average age of 65 years and 53% females. A total of 139 patients were diagnosed with PE by CT angiography. The presence of factors with a high NPV showed a sensitivity of 100% in low-risk patients according to Wells, with sensitivity dropping below 50% in other populations. The association of these factors in the PERC plus criteria would allow a reduction of up to 34% in CT angiographies in patients with low risk according to the Wells scale.

CONCLUSIONS

The combination of risk stratification of the Wells scale and PERC plus criteria allows an absolute reduction of 34.3% in the performance of CT angiographies in patients classified as low risk with a sensitivity and a negative predictive value of 100%. The preexistence of an alternative diagnosis does not allow ruling out PE in patients with intermediate or high risk according to the Wells scale.

Pulmonary Embolism Management Audit and Machine Learning Analysis of Delayed Anticoagulation in a Swiss Teaching Hospital

Background/Objectives: Diagnosing acute pulmonary embolism (PE) is challenging due to its wide range of symptoms and numerous differential diagnoses. Medical professionals must balance performing all essential examinations and avoiding unnecessary testing. This study aimed to retrospectively audit the diagnosis and treatment of acute PE at a Swiss public teaching hospital to determine the adherence to current guidelines and to identify the factors associated with the delayed initiation of anticoagulation in PE patients. Methods: In this retrospective observational cohort study, we included all adult patients hospitalized with PE at the Cantonal Hospital Baselland (KSBL) between November 2018 and October 2020, where the diagnosis was made within the first twelve hours of their arrival to the emergency department (ED). LASSO regression was employed to identify clinical characteristics associated with delayed anticoagulation initiation. Results: A total of 197 patients were included (mean age: 70 years, 54% female). The audit revealed that diagnostic workup was conducted according to guidelines in 57% of cases. Often, D-dimer levels were measured although not strictly necessary (70%). Pretest probability was assessed and documented using the Wells or Geneva score in only 3% of patients, and risk assessment via the Pulmonary Embolism Severity Index (PESI) score was documented in 21% of patients. The median time from ED arrival to CT scan was 120 min (IQR 89.5-210.5), and the median time to anticoagulation initiation was 193 min (IQR 145-277). Factors identified by LASSO associated with delayed anticoagulation included prolonged time from ED arrival to CT scan, the presence of distended jugular veins on examination, ED arrival in the morning, and presenting symptoms of weakness or tiredness. Complementary leg ultrasound was performed in 57% of patients, with 38% of these cases lacking prior clinical examination for deep vein thrombosis. The duration of the anticoagulation treatment was not specified in the discharge report for 17% of patients. A medical follow-up after discharge was recommended in 75% of the patients. Conclusions: In conclusion, while the management of PE at the KSBL generally adheres to high standards, there are areas for improvement, particularly in the morning performance, the use of a pretest probability assessment, D-dimer measurement, risk assessment via the PESI score, the performance of complementary leg ultrasounds, clarification of the anticoagulation duration, and follow-up management.

A cross-sectional analysis of four common clinical decision rules for pulmonary embolism, Mashhad, Iran

Introduction

Pulmonary embolism (PE) is a potentially fatal condition. Several non-invasive clinical decision rules (CDRs) were developed for the safe exclusion of PE. All CDRs used to safely rule out PE have been created and tested within hospital or acute care environments. However, CDRs that are designed in one specific setting may not perform as effectively when used in a different setting. In this study, we aimed to compare the performance of four common CDRs; Wells Score, Simplified Wells Score, revised Geneva Score, and simplified revised Geneva Score.

Methods

This was a cross-sectional study in which patients suspected of PE presenting to Imam Reza Hospital or Ghaem Hospital were recruited from September 23, 2013, to March 19, 2016 in Mashhad, Iran. The specificity, sensitivity, and accuracy were utilized as metrics to compare the CDRs in our region.

Results

Two hundred and forty patients were included in the study. The mean age of patients was 57.91±19.97 years, and 54.16% of them (n=130) were female. 120 patients were confirmed to have PE with CT angiography. Wells score showed the highest sensitivity (90.4%) and revised Geneva score represented the highest specificity (84.9%). The highest accuracy belongs to the simplified Wells score (62.3%).

Conclusion

In this study, we demonstrated that the Wells criteria with its high sensitivity, can be used as a score for screening, and the revised Geneva score with its high specificity, can be used in the second stage for healthy people who have been diagnosed as unhealthy by the Wells score.

Beyond pulmonary embolism: Alternative diagnosis and incidental findings on CT pulmonary angiography in sickle cell disease

BACKGROUND

Sickle cell disease (SCD) is a genetic hematological disorder associated with severe complications, such as vaso-occlusive crises, acute chest syndrome (ACS), and an increased risk of thromboembolic events, including pulmonary embolism (PE). The diagnosis of PE in SCD patients presents challenges due to the overlapping symptoms with other pulmonary conditions. Our previous study revealed that nearly 96% of computed tomography pulmonary angiography (CTPA) scans in SCD patients were negative for PE, highlighting a gap in understanding the significance of CTPA findings when PE is absent.

METHODS

In this retrospective follow-up study conducted at the Salmaniya Medical Complex in Bahrain, we examined SCD patients with HbSS genotypes who underwent CTPA from January 1, 2018, to December 31, 2021, for suspected PE, but the results were negative. The aim of this study was to identify alternative diagnoses and incidental findings from CTPA scans. Experienced radiologists reviewed the CTPA images and reports to assess potential alternative diagnoses and incidental findings, incorporating an additional analysis of chest X-rays to evaluate the diagnostic value of CTPA. Incidental findings were classified based on their location and clinical significance.

RESULTS

Among the 230 evaluated SCD patients (average age 39.7 years; 53% male) who were CTPA negative for PE, 142 (61.7%) had identifiable alternative diagnoses, primarily pneumonia (49.1%). Notably, 88.0% of these alternative diagnoses had been previously suggested by chest radiographs. Furthermore, incidental findings were noted in 164 (71.3%) patients, with 11.0% deemed clinically significant, necessitating immediate action, and 87.8% considered potentially significant, requiring further assessment. Notable incidental findings included thoracic abnormalities such as cardiomegaly (12.2%) and an enlarged pulmonary artery (11.3%), as well as upper abdominal pathologies such as hepatomegaly (19.6%), splenomegaly (20.9%), and gallstones (10.4%).

CONCLUSION

This study underscores the limited additional diagnostic yield of CTPA for identifying alternative diagnoses to PE in SCD patients, with the majority of diagnoses, such as pneumonia, already suggested by chest radiographs. The frequent incidental findings, most of which necessitate further evaluation, highlight the need for a cautious and tailored approach to using CTPA in the SCD population.

Positive rate and quality assessment of CT pulmonary angiography in sickle cell disease: a case‒control study

BACKGROUND

Pulmonary complications are common in sickle cell disease (SCD) and can mimic pulmonary embolisms (PEs), leading to potential overuse of computed tomography pulmonary angiography (CTPA). Maximizing the quality of CTPA is essential for its diagnostic accuracy. However, little is known about the positive rate and quality of CTPA in SCD.

METHODS

This retrospective case‒control study aimed to determine the positive rate and quality of CTPA studies performed to rule out PE in SCD (HbSS genotype) patients compared to a control group. Logistic regression analysis was used to identify independent factors associated with suboptimal CTPA studies, defined as a mean enhancement of < 210 HU in the pulmonary artery.

RESULTS

The study included 480 patients, consisting of 240 SCD patients and 240 controls. The positive rate of PE was 4.0%, with a similar rate in both SCD patients and the control group (4.2% vs. 3.8%, p = 0.08). However, SCD patients had significantly lower contrast enhancement of the pulmonary artery than the control group (266.1 ± 90.5 HU vs. 342.2 ± 116.1 HU, p < 0.01). Notably, 25.4% of SCD patients had suboptimal scans. The logistic regression model demonstrated that SCD was significantly associated with suboptimal pulmonary arterial contrast enhancement compared to the control group (OR = 4.4; 95% CI: 2.4-8.3).

CONCLUSIONS

This study revealed a relatively low positive rate of CTPA in both SCD patients and the control group. However, SCD was significantly associated with suboptimal image quality due to inadequate contrast enhancement of the pulmonary artery. Further research is needed to identify measures that can enhance the quality of CTPA studies in SCD patients and to establish a specific imaging protocol for this patient population.

Poor adherence to the recommended pulmonary embolism diagnostic pathway in the emergency department: A retrospective cohort study

OBJECTIVES

Pulmonary embolus (PE) is a form of venous thromboembolism associated with increased morbidity and mortality if not diagnosed and treated early. Variations in clinical presentation make the diagnosis challenging. The gold standard for diagnosing PE is a computed tomography pulmonary angiogram (CTPA). Physicians show a low threshold for over-investigating PE. The evaluation of patients with suspected PE should be efficient, including but not limited to the use of risk stratification methods. This study aims to assess the adherence to the recommended diagnostic pathways of ordering CTPAs in patients with suspected PE.

METHODS

This retrospective cohort study included patients above 18 years of age who received a CTPA for a suspected PE in the emergency department (ED) of a hospital between 2015 and 2019. Patient demographic data, chief complaint, variables of the Wells and pulmonary emboli rule-out criteria scores, pregnancy status, investigations, and the patient's final PE diagnosis were extracted from the hospital electronic medical records. Diagnostic pathways that took place were compared to the internationally recommended pathway.

RESULTS

Four hundred and eighty-six patients were included in this study. The mean age was 51.01 (±19.5) years, and 377 (69.3%) patients were female. The recommended PE diagnostic pathway to order CTPA was incorrectly followed in 288 patients (59.3%). Seventy-five (15.4%) patients received an unnecessary CTPA. D-dimer test was ordered unnecessarily in 144 patients (29.6%). The overall prevalence of PE in our population was 9.47% (n: 46). Out of the 75 unnecessarily ordered CTPAs, 2 (2.7%) showed PE, while CTPAs ordered using the correct pathway showed 31 (10.9%) PEs.

CONCLUSION

Our study revealed that approximately two-thirds of all CTPA requests did not adhere to the recommended PE clinical decision pathway. There was a significant improper and unnecessary utilization of CTPA imaging and D-dimer testing. Improvements seem imperative to enhance physicians' clinical approach to PE diagnosis.

Risk factors for hospital outcomes in pulmonary embolism: A retrospective cohort study

Background

Pulmonary embolism (PE) is not only a life-threatening disease but also a public health issue with significant economic burden. The aim of the study was to identify factors-including the role of primary care-that predict length of hospital stay (LOHS), mortality and re-hospitalization within 6 months of patients admitted for PE.

Method

A retrospective cohort study was conducted with patients presenting to a Swiss public hospital with PE diagnosed at the hospital between November 2018 and October 2020. Multivariable logistic and zero-truncated negative binomial regression analyses were performed to assess risk factors for mortality, re-hospitalization and LOHS. Primary care variables encompassed whether patients were sent by their general practitioner (GP) to the emergency department and whether a GP follow-up assessment after discharge was recommended. Further analyzed variables were pulmonary embolism severity index (PESI) score, laboratory values, comorbidities, and medical history.

Results

A total of 248 patients were analyzed (median 73 years and 51.6% females). On average patients were hospitalized for 5 days (IQR 3-8). Altogether, 5.6% of these patients died in hospital, and 1.6% died within 30 days (all-cause mortality), 21.8% were re-hospitalized within 6 months. In addition to high PESI scores, we detected that, patients with an elevated serum troponin, as well as with diabetes had a significantly longer hospital stay. Significant risk factors for mortality were elevated NT-proBNP and PESI scores. Further, high PESI score and LOHS were associated with re-hospitalization within 6 months. PE patients who were sent to the emergency department by their GPs did not show improved outcomes. Follow-up with GPs did not have a significant effect on re-hospitalization.

Conclusion

Defining the factors that are associated with LOHS in patients with PE has clinical implications and may help clinicians to allocate adequate resources in the management of these patients. Serum troponin and diabetes in addition to PESI score might be of prognostic use for LOHS. In this single-center cohort study, PESI score was not only a valid predictive tool for mortality but also for long-term outcomes such as re-hospitalization within 6 months.

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.

Trauma-induced pulmonary thromboembolism: What's update?

Trauma-induced pulmonary thromboembolism is the second leading cause of death in severe trauma patients. Primary fibrinolytic hyperactivity combined with hemorrhage and consequential hypercoagulability in severe trauma patients create a huge challenge for clinicians. It is crucial to ensure a safe anticoagulant therapy for trauma patients, but a series of clinical issues need to be answered first, for example, what are the risk factors for traumatic venous thromboembolism? How to assess and determine the status of coagulation dysfunction of patients? When is the optimal timing to initiate pharmacologic prophylaxis for venous thromboembolism? What types of prophylactic agents should be used? How to manage the anticoagulation-related hemorrhage and to determine the optimal timing of restarting chemoprophylaxis? The present review attempts to answer the above questions.

Diagnosing pulmonary thromboembolism: Concerns and controversies

Pulmonary thromboembolism (PTE) is an important cause of mortality/morbidity even today despite advancement in clinical understanding as well as diagnostic facilities. Clinical diagnosis of PTE is often challenging because of nonspecific sign/symptoms. Adherence to clinical decision-making protocols and appropriate use of diagnostic modalities like computed tomography pulmonary angiography can resolve the diagnostic dilemma in most cases and help in the overall management of PTE. This article deals with various concerns as well as controversies surrounding accurate diagnosis of PTE as on date.

Determinants of time-to-disposition in patients who underwent CT for pulmonary embolism: a retrospective study

Background

Pulmonary embolism (PE) is a common life-threatening medical emergency that needs prompt diagnosis and management. Providing urgent care is a key determinant of quality in the emergency department (ED) and time-based targets have been implemented to reduce length of stay and overcrowding. The study aimed to determine factors that are associated with having a time-to-disposition of less than 4 h in patients with suspected PE who underwent computed tomography pulmonary angiography (CT-PA) to confirm the diagnosis.

Methods

After obtaining approval from the ethics committee, we conducted a retrospective observational study by examining CT-PA scans that was performed to rule out PE in all adult patients presenting at the ED between January 2018 and December 2019. Demographic information and clinical information, as well as arrival and disposition times were collected from electronic health records. Multivariable regression analysis was used to identify the independent factors associated with meeting the 4-h target in the ED.

Results

In total, the study involved 232 patients (76 men and 156 women). The median length of stay in the ED was 5.2 h and the 4-h target was achieved in 37% of patients. Multivariable logistic regression analysis revealed that a positive CT-PA scan for PE was independently associated with meeting the four-hour target in the ED (odds ratio [OR]: 2.2; 95% CI: 1.1–4.8). Furthermore, Hemoptysis was the only clinical symptom that served as an independent factor associated with meeting the 4-h target in the ED (OR: 10.4; 95% CI: 1.2–90.8).

Conclusion

Despite the lower number of staff and higher volume of patients on weekends, patients who presented on weekends had shorter stays and were more likely to meet the 4-h target. Careful clinical assessment, prior to requesting a CT-PA scan, is crucial, since negative CT-PA scans may be associated with failure to meet the 4-h target.