Diagnostic accuracy of focused deep venous, lung, cardiac and multiorgan ultrasound in suspected pulmonary embolism: a systematic review and meta-analysis

POCUS for Thrombus: Emphasizing the Importance of Initial Point-of-Care Ultrasound in the Management of Pulmonary Thromboembolism

Pulmonary embolism (PE) constitutes a substantial health burden among individuals in the United States. It ranks as the third most common cause of cardiovascular death aside from stroke and myocardial infarction. Diagnostic errors are common with PE as patients can present with non-specific symptoms or could be completely asymptomatic with PE being an incidental finding. Diagnostic errors can result in missed or late diagnosis of PE, which, in turn, increases health care costs, morbidity, and mortality rates. Hence, early diagnosis is crucial. Computed tomography pulmonary angiography (CTPA) remains the gold standard in PE diagnosis, despite exposure to high doses of radiation. Point-of-care ultrasound (POCUS) is an underutilized, non-invasive technique that aids in the early diagnosis of PE and can safely reduce the radiation from CTPA in cases where contraindication exists. POCUS has been shown to have a high sensitivity and specificity for early diagnosis of PE.

Point-of-Care Lung Ultrasound in Emergency Medicine: A Scoping Review With an Interactive Database

BACKGROUND

This scoping review was conducted to provide an overview of the evidence of point-of-care lung ultrasound (LUS) in emergency medicine. By emphasizing clinical topics, time trends, study designs, and the scope of the primary outcomes, a map is provided for physicians and researchers to guide their future initiatives.

RESEARCH QUESTION

Which study designs and primary outcomes are reported in published studies of LUS in emergency medicine?

STUDY DESIGN AND METHODS

We performed a systematic search in the PubMed/MEDLINE, Embase, Web of Science, Scopus, and Cochrane Library databases for LUS studies published prior to May 13, 2023. Study characteristics were synthesized quantitatively. The primary outcomes in all papers were categorized into the hierarchical Fryback and Thornbury levels.

RESULTS

A total of 4,076 papers were screened and, following selection and handsearching, 406 papers were included. The number of publications doubled from January 2020 to May 2023 (204 to 406 papers). The study designs were primarily observational (n = 375 [92%]), followed by randomized (n = 18 [4%]) and case series (n = 13 [3%]). The primary outcome measure concerned diagnostic accuracy in 319 papers (79%), diagnostic thinking in 32 (8%), therapeutic changes in 4 (1%), and patient outcomes in 14 (3%). No increase in the proportions of randomized controlled trials or the scope of primary outcome measures was observed with time. A freely available interactive database was created to enable readers to search for any given interest (https://public.tableau.com/app/profile/blinded/viz/LUSinEM_240216/INFO).

INTERPRETATION

Observational diagnostic studies have been produced in abundance, leaving a paucity of research exploring clinical utility. Notably, research exploring whether LUS causes changes to clinical decisions is imperative prior to any further research being made into patient benefits.

Initial Evaluation and Management of Patients Presenting with Acute Chest Pain in the Emergency Department

PURPOSE OF THE REVIEW

To review the initial evaluation of chest pain in the emergency department (ED), with a focus on coronary artery disease (CAD) and acute coronary syndromes (ACS), using consensus statements from major cardiovascular disease organizations.

RECENT FINDINGS

Major cardiovascular organizations have released consensus statements on this topic, notably the 2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR Guideline for the Evaluation and Diagnosis of Chest Pain and the 2022 ACC Expert Consensus Decision Pathway on the Evaluation and Disposition of Acute Chest Pain in the Emergency Department. Also, recent studies have evaluated the use of high sensitivity troponin (hs-cTn) to safely rule out myocardial infarction (MI), with the development of rule-out pathways designed to be utilized in the ED. This review highlights the comprehensive differential diagnoses of chest pain in the ED and urgent management of these etiologies, with a focus on cardiovascular etiologies. There exist a few rule-out pathways recommended by major cardiovascular organizations, notably the high-STEACS and the ESC 0/1 and 0/2 pathways that can safely and quickly discharge patients with low risk of MI.

Comparison of international guideline recommendations for the diagnosis of pulmonary embolism

Pulmonary embolism is one of the leading causes of death due to cardiovascular disease. Timely diagnosis is crucial, but challenging, as the clinical presentation of pulmonary embolism is unspecific and easily mistaken for other common medical emergencies. Clinical prediction rules and D-dimer measurement allow stratification of patients into groups of expected prevalence and are key elements in adequate selection of patients for diagnostic imaging; however, the strengths and weaknesses of the multiple proposed prediction rules, when to measure D-dimer, and which cutoff to apply might be elusive to a significant proportion of physicians. 13 international guidelines authored by medical societies or expert author groups provide recommendations on facets of the diagnostic investigations in suspected pulmonary embolism, some of which are hallmarked by pronounced heterogeneity. This Review summarises key recommendations of each guideline, considers the most recent evidence on the topic, compares guideline recommendations on each facet of the diagnosis of pulmonary embolism, and provides a synthesis on the most common recommendations.

What echocardiographic findings differentiate acute pulmonary embolism and chronic pulmonary hypertension?

BACKGROUND

Pulmonary embolism (PE) and pulmonary hypertension (PH) are potentially fatal disease states. Early diagnosis and goal-directed management improve outcomes and survival. Both conditions share several echocardiographic findings of right ventricular dysfunction. This can inadvertently lead to incorrect diagnosis, inappropriate and potentially harmful management, and delay in time-sensitive therapies. Fortunately, bedside echocardiography imparts a few critical distinctions.

OBJECTIVE

This narrative review describes eight physiologically interdependent echocardiographic parameters that help distinguish acute PE and chronic PH. The manuscript details each finding along with associated pathophysiology and summarization of the literature evaluating diagnostic utility. This guide then provides pearls and pitfalls with high-quality media for the bedside evaluation.

DISCUSSION

The echocardiographic parameters suggesting acute or chronic right ventricular dysfunction (best used in combination) are: 1. Right heart thrombus (acute PE) 2. Right ventricular free wall thickness (acute ≤ 5 mm, chronic > 5 mm) 3. Tricuspid regurgitation pressure gradient (acute ≤ 46 mmHg, chronic > 46 mmHg, corresponding to tricuspid regurgitation maximal velocity ≤ 3.4 m/sec and > 3.4 m/sec, respectively) 4. Pulmonary artery acceleration time (acute ≤ 60-80 msec, chronic < 105 msec) 5. 60/60 sign (acute) 6. Pulmonary artery early-systolic notching (proximally-located, higher-risk PE) 7. McConnell's sign (acute) 8. Right atrial enlargement (equal to left atrial size suggests acute, greater than left atrial size suggests chronic).

CONCLUSIONS

Emergency physicians must appreciate the echocardiographic findings and associated pathophysiology that help distinguish acute and chronic right ventricular dysfunction. In the proper clinical context, these findings can point towards PE or PH, thereby leading to earlier goal-directed management.

Acute pulmonary embolism: Diagnosis and management

Acute pulmonary embolism (PE) can present with non-specific signs and symptoms and thus the diagnosis and management might not be as straightforward. This review outlines the new PE management guidelines in the Indian context. The exact prevalence in the Indian population is not well defined; despite recent studies suggesting an increasing trend in the Asian population. A delay in treatment can be fatal, especially in massive PE. The nuances associated with stratification and management have led to heterogeneity in acute PE management. The purpose of the review is. 1: To highlight the principles of stratification, diagnosis and management of acute PE with a special attention towards the Indian population. 2: To aid patient selection for newer catheter based therapies. To conclude, formulation of pulmonary embolism guidelines in the Indian setting is required underlying the role of further research in this area.

Multiorgan ultrasonographic findings in patients with pulmonary embolism at diagnosis and clinical follow-up: a proof of concept study

PURPOSE

The purpose of this descriptive feasibility study was to assess the clinical impact and feasibility of conducting a multiorgan ultrasound examination of patients with pulmonary embolism at both time of diagnosis and at clinical follow-up.

METHODS

Hemodynamically stable patients with pulmonary embolism verified by CT pulmonary angiography or ventilation perfusion scintigraphy were eligible for inclusion. Enrolled patients underwent multiorgan ultrasound investigation encompassing echocardiography supplemented with focused lung and deep venous ultrasound emphasizing right ventricular strain, subpleural consolidations and presence of deep venous thrombi. Identical investigations were conducted at 3 months follow-up. The presence of ultrasonographic findings at diagnosis and follow-up was compared and the clinical impact of any remaining pathology or strain was described.

RESULTS

Twenty-one patients were enrolled in the study of whom 20 survived to attend follow-up. Mean age was 62 ± 15 years and 48% were female. At diagnosis, the most prevalent ultrasonographic findings were subpleural consolidations in 11 patients and right ventricular dilation in eight. At follow-up, signs of right ventricular strain had resolved in all patients. However, in one patient, no resolution was seen in a subpleural consolidation observed at the time of pulmonary embolism diagnosis, resulting in referral to a chest CT. Additionally, one patient exhibited residual deep venous thrombotic material, leading to prolongation of anticoagulative treatment.

CONCLUSION

In patients with pulmonary embolism, multiorgan ultrasound is feasible in follow-up and adequately powered studies should determine the clinical utility of such an approach.

Point-of-care ultrasound improves clinical outcomes in patients with acute onset dyspnea: a systematic review and meta-analysis

The early, appropriate management of acute onset dyspnea is important but often challenging. The aim of this study was to investigate the effects of the use of Point-of-Care Ultrasound (PoCUS) versus conventional management on clinical outcomes in patients with acute onset dyspnea. The Cochrane Library, MEDLINE, EMBASE and reference lists were searched to identify eligible trials (inception to October 14, 2021). There were no language restrictions. Randomized controlled trials (RCTs), and prospective and retrospective cohort studies that compared PoCUS with conventional diagnostic modalities (controls) in patients with acute onset dyspnea were included. Two independent reviewers extracted data and assessed the risk of bias. Disagreements were resolved by consensus. The primary study outcomes were time to diagnosis, time to treatment, and length of stay (LOS). Secondary outcomes included rate of appropriate treatment, 30-day re-admission rate, and mortality. We included eight RCTs and six observational studies with a total of 5393 participants. Heterogeneity across studies was variable (from low to considerable), with overall low or moderate study quality and low or moderate risk of bias (except one article with serious risk of bias). Time to diagnosis (mean difference [MD], - 63 min; 95% CI, - 115 to - 11 min] and time to treatment (MD, - 27 min; 95% CI - 43 to - 11 min) were significantly shorter in the PoCUS group. In-hospital LOS showed no differences between the two groups, but LOS in the Intensive Care Unit (MD, - 1.27 days; - 1.94 to - 0.61 days) was significantly shorter in the PoCUS group. Patients in the PoCUS group showed significantly higher odds of receiving appropriate therapy compared to controls (odds ratio [OR], 2.31; 95% CI, 1.61-3.32), but there was no significant effect on 30-day re-admission rate and in-hospital or 30-day mortality. Our results indicate that PoCUS use contributes to early diagnosis and better outcomes compared to conventional methods in patients admitted with acute onset dyspnea.

Diagnostic Accuracy of a Bespoke Multiorgan Ultrasound Approach in Suspected Pulmonary Embolism

Purpose The aims of this study were to prospectively assess the diagnostic accuracy of a bespoke multiorgan point-of-care ultrasound approach for suspected pulmonary embolism and evaluate if this model allows reduced referral to further radiation diagnostics while maintaining safety standards. Materials and Methods Patients with suspected pulmonary embolism referred for CT pulmonary angiography or ventilation/perfusion scintigraphy were included as a convenience sample. All patients were subject to blinded ultrasound investigation with cardiac, lung, and deep venous ultrasound. The sensitivity and specificity of applied ultrasound signs and the hypothetical reduction in the need for further diagnostic workup were calculated. Results 75 patients were prospectively enrolled. The Wells score was below 2 in 48 patients, between 2 and 6 in 24 patients, and above 6 in 3 patients. The prevalence of pulmonary embolism was 28%. The most notable ultrasound signs were presence of a deep venous thrombus, at least two hypoechoic pleural-based lesions, the D-sign, the 60/60-sign, and a visible right ventricular thrombus which all had a specificity of 100%. Additionally, a multiorgan ultrasound investigation with no findings compatible with pulmonary embolism yielded a sensitivity of 95.2% (95%CI: 76.2-99.9). CT or scintigraphy could be safely avoided in 70% of cases (95%CI: 63.0-83.1%). Conclusion The findings of our study suggest that implementation of a multiorgan ultrasound assessment in patients with suspected pulmonary embolism may safely reduce the need for CT or scintigraphy by confirming or dismissing the suspicion.

Diagnosing Pulmonary Embolism Using Point-of-Care Ultrasound in a Patient With Malingering and Coccidioidomycosis Infection

We report a case of a 41-year-old male diagnosed with pulmonary coccidioidomycosis and pulmonary embolism (PE) based on a point-of-care ultrasound (POCUS) finding who was suspected to be malingering for right-sided chest pain considering his psychiatric history. POCUS was performed and showed right ventricular strain with a D-shaped left ventricle and B-lines with subpleural consolidations, and PE was confirmed with computed tomography pulmonary angiography. No other risk factors for PE were found except for coccidioidomycosis. The patient was treated with apixaban and fluconazole and discharged in stable condition. We discuss the usefulness of POCUS in diagnosing PE and the very rare association between coccidioidomycosis and PE.

Point‑of‑Care Ultrasound in internal medicine

Point-of-Care ultrasound (POCUS) is bedside ultrasound examination performed by a clinician. POCUS is a suitable tool for rapid diagnosis and monitoring of the condition of many patients examined by internists in emergency departments and inpatient departments. POCUS allows the examining physician to supplement the physical examination with additional information obtained in real time, and is a useful tool for differential diagnosis of a number of acute conditions (shock, shortness of breath, etc.). Chest POCUS includes an indicative assessment of cardiac function and evaluation of the lung parenchyma, including exclusion of pericardial effusion, pneumothorax or fluidothorax. One of the most common applications of POCUS is to assess the state of the venous filling by examining the inferior vena cava. When examining the abdomen, the internist should at least be able to diagnose fluid in the abdominal cavity and exclude congestion in the hollow system of the kidney. POCUS for internists also includes examination of main venous trunks to rule out proximal venous thrombosis. Even when performing conventional invasive procedures, we cannot do without ultrasound at the bedside, whether it is a puncture of ascites or pleural effusion, or cannulation of the central vein. The advantage of POCUS is the immediate availability of the examination and the possibility to repeat scans when needed for monitoring the patient's condition.

Interesting case of incidental diagnosis of pulmonary embolism by endobronchial ultrasonography

Pulmonary embolism (PE) is the obstruction of the pulmonary artery or its branches, usually by a thrombus that originates in the lower extremity veins. PE is associated with high mortality risk. Here, we present the case of a patient who initially presented with dysphagia. Chest radiography revealed a lung nodule. Endobronchial ultrasonography (EBUS) was performed to evaluate the nodule, which revealed a pulmonary embolus. Subsequently, CT angiography of the chest was performed to confirm the diagnosis of PE. Anticoagulation therapy was initiated. The biopsy results were positive for lung adenocarcinoma. There are only few reported cases of PE diagnosed using EBUS. Here, the patient had not presented with the signs and symptoms of PE. Had PE not been diagnosed by EBUS, our patient could have potentially had a disastrous outcome. Moreover, this case shows that EBUS may be used for diagnosing PE.

A cross-sectional survey on the lung ultrasound training and practice of respiratory therapists in mainland China

Purpose

This national study aimed to investigate the lung ultrasound (LUS) training and practice of respiratory therapists (RTs) in mainland China.

Methods

A cross-sectional multicenter survey was conducted from May 22, 2021 to August 12, 2021, through online platforms. This survey included RTs in mainland China. The survey was divided into four sections: (1) demographic characteristics and basic information; (2) basic information about LUS training and practice; (3) LUS practice details; and (4) Other ultrasound training and practice.

Results

A total of 514 responses were received, and 494 valid responses were included in the analysis. 81.2% (401/494) participants’ highest degree of education was a bachelor’s degree, and 43.1% (213/494) participants were at level II in terms of job ranking. 99.2%(490/494) participants agreed that the RTs needed to learn lung ultrasound, but only 12.3% (61/494) participants had received a LUS training course. Further, 66.2% (327/494) experienced participants responded to Sect. 3. Most of RTs used LUS when the patient had hypoxia (265/327, 81%) or dyspnea (260/317, 79.5%); they also used it during spontaneous breathing trial(SBT) (191/327, 58.4%) or in prone position (177/327, 54.1%). The A-line (302/327, 92.4%), B-line (299/327, 91.4%), lung slide (263/327, 80.4%), and bat sign (259/327, 79.2%) were well known as LUS signs. Also, 30.6% (100/327) participants did not use the LUS protocol in their clinical practice, and only 25.4%(83/327) participants said they had used LUS scores. Moreover, 55.7% (182/327) participants frequently changed the respiratory therapy strategy according to LUS results.

Conclusions

We should improve the number and workplace of RTs in mainland China in the future. We should also standardize the application of LUS practice and training for RTs in mainland China and establish corresponding certification pathways.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02213-6.

Clinical Characteristics and Risk Factors for Early versus Late Pulmonary Embolism in Trauma Patients: A Retrospective, Observational Study

Background

We sought to evaluate the clinical characteristics and risk factors for early versus late pulmonary embolism (PE) in trauma patients.

Methods

This was a retrospective analysis of injured patients who presented with a confirmed PE between 2013 and 2019. Data were analysed and compared for patients with early PE (≤4 days) versus late PE (>4 days post-trauma).

Results

The study included 82 consecutive trauma patients with confirmed diagnosis of PE. The mean age of patients was 42.3 ± 16.2 years. The majority were males (79.3%) and the median time from injury to PE was 10 days. Of the PE cases, 24 (29.3%) had early PE, while 58 (70.7%) had late PE. The early PE group had higher rates of surgical intervention within 24 hours of admission than the late PE group (p = 0.001). Also, the rate of sub-segmental thrombi was significantly higher in the early PE group (p = 0.01). The late PE group sustained more moderate-to-severe injuries ie, GCS ED <13 (p = 0.03) and the median time from injury to PE diagnosis was 15 days (p = 0.001). After adjusting for the potential covariates, surgery within 24 hours of admission [adjusted odds ratio 37.58 (95% confidence interval 3.393-416.20), p = 0.003] was found to be significant independent predictor of early PE in trauma patients.

Conclusion

One-third of post-trauma PEs occurs early after trauma and the surgical intervention within the first 24 hours of admission is a major risk factor. A prospective study is needed to develop an objective risk assessment for the prevention and detection of early and late PE post-trauma.

Diagnostic accuracy of multiorgan point-of-care ultrasound compared with pulmonary computed tomographic angiogram in critically ill patients with suspected pulmonary embolism

BACKGROUND

Critically ill patients have a higher incidence of pulmonary embolism (PE) than non-critically ill patients, yet no diagnostic algorithm has been validated in this population, leading to the overuse of pulmonary artery computed tomographic angiogram (CTA). This study aimed to comparatively evaluate the diagnostic accuracy of point-of-care ultrasound (POCUS) combined with laboratory data versus CTA in predicting PE in critically ill patients.

METHODS

A prospective diagnostic accuracy study. Critically ill patients with suspected acute PE undergoing CTA were prospectively enrolled. Demographic and clinical data were collected from electronic medical records. Blood samples were collected, and the Wells and revised Geneva scores were calculated. Standardized multiorgan POCUS and CTA were performed. The discriminatory power of multiorgan POCUS combined with biochemical markers was tested using ROC curves, and multivariate analysis was performed.

RESULTS

A total of 88 patients were included, and 37 (42%) had PE. Multivariate analysis showed a relative risk (RR) of PE of 2.79 (95% CI, 1.61-4.84) for the presence of right ventricular (RV) dysfunction, of 2.54 (95% CI, 0.89-7.20) for D-dimer levels >1000 ng/mL, and of 1.69 (95% CI, 1.12-2.63) for the absence of an alternative diagnosis to PE on lung POCUS or chest radiograph. The combination with the highest diagnostic accuracy for PE included the following variables: 1- POCUS transthoracic echocardiography with evidence of RV dysfunction; 2- lung POCUS or chest radiograph without an alternative diagnosis to PE; and 3- plasma D-dimer levels >1000 ng/mL. Combining these three findings resulted in an area under the curve of 0.85 (95% CI, 0.77-0.94), with 50% sensitivity and 96% specificity.

CONCLUSIONS

Multiorgan POCUS combined with laboratory data has acceptable diagnostic accuracy for PE compared with CTA. The combined use of these methods might reduce CTA overuse in critically ill patients.

The Diagnostic Value of Bedside Echocardiography and Lower Extremity Blood Vessels in Acute Pulmonary Embolism

Objective

The study aimed to evaluate the value of bedside echocardiography (TTE) and lower extremity blood vessels in diagnosis and prognosis of acute pulmonary embolism (APE).

Methods

A retrospective study was performed on 53 patients with APE diagnosed by CT pulmonary angiography (CTPA) (systemic systolic blood pressure was >90 mmHg at time of consultation, and systemic systolic blood pressure decreased by <40 mmHg compared with basic value in those with hypertension). All patients underwent TTE examination before treatment. The high-risk factors, clinical manifestations, laboratory tests, and prognosis were retrospectively analyzed.

Results

The rate of PE-related deterioration (cardiopulmonary resuscitation, tracheal intubation, cardiogenic shock, and death) within 14 days of hospitalization in RVD was 28%, and mortality rate (sudden death) was 20%, compared with non-RVD (both 0%). TTE examination showed that RVD as a predictor of pulmonary embolism-related death had a sensitivity of 100%, a specificity of 58%, a positive predictive value of 20%, and a negative predictive value of 100%.

Conclusions

(1) TTE has increasingly shown obvious advantages in diagnosis of APE. It can detect direct or indirect signs of pulmonary embolism, confirm diagnosis or suspected diagnosis, and noninvasively and dynamically observe hemodynamic changes of heart in patients with acute PTE before and after treatment.. (2) The PE-related exacerbation rate (28%) or mortality (20%) of APE patients in normotensive with RVD was higher without RVD (0%). RVD is an independent predictor of poor prognosis in normotensive acute PTE. TTE tests allow people to identify people at risk of early death. The short-term prognosis of patients without RVD was better (14 days).

Multi-organ point-of-care ultrasound for detection of pulmonary embolism in critically ill COVID-19 patients - A diagnostic accuracy study

Purpose

Critically ill COVID-19 patients have an increased risk of developing pulmonary embolism (PE). Diagnosis of PE by point-of-care ultrasound (POCUS) might reduce the need for computed tomography pulmonary angiography (CTPA), while decreasing time-to-diagnosis.

Materials & methods

This prospective, observational study included adult ICU patients with COVID-19. Multi-organ (lungs, deep vein, cardiac) POCUS was performed within 24 h of CTPA, looking for subpleural consolidations, deep venous thrombosis (DVT), and right ventricular strain (RVS). We reported the scan time, and calculated diagnostic accuracy measures for these signs separately and in combination.

Results

70 consecutive patients were included. 23 patients (32.8%) had a PE. Median scan time was 14 min (IQR 11–17). Subpleural consolidations' diagnostic accuracy was: 42.9% (95%CI [34.1–52.0]). DVT's and RVS' diagnostic accuracy was: 75.6% (95%CI [67.1–82.9]) and 74.4% (95%CI [65.8–81.8]). Their sensitivity was: 24.0% (95%CI [9.4–45.1]), and 40.0% (95%CI [21.3–61.3]), while their specificity was: 88.8% (95%CI [80.8–94.3]), and: 83.0% (95%CI [74.2–89.8]), respectively. Multi-organ POCUS sensitivity was: 87.5% (95%CI [67.6–97.3]), and specificity was: 25% (95%CI [16.9–34.7]).

Conclusions

Multi-organ rather than single-organ POCUS can be of aid in ruling out PE in critically ill COVID-19 and help select patients for CTPA. In addition, finding RVS can make PE more likely, while a DVT would preclude the need for a CTPA.

Registration: www.trialregister.nl: NL8540.