Emergency thoracic ultrasound in the differentiation of the etiology of shortness of breath (ETUDES): sonographic B-lines and N-terminal pro-brain-type natriuretic peptide in diagnosing congestive heart failure

POCUS literature primer: key papers on cardiac and lung POCUS

OBJECTIVE

Although point of care ultrasound (POCUS) use has become prevalent in medicine, clinicians may not be familiar with the evidence supporting its utility in patient care. The objective of this study is to identify the top five most influential papers published on the use of cardiac POCUS and lung POCUS in adult patients.

METHODS

A 14-member expert panel from the Canadian Association of Emergency Physicians (CAEP) Emergency Ultrasound Committee and the Canadian Ultrasound Fellowship Collaborative used a modified Delphi process. Panel members are ultrasound fellowship trained or equivalent, are engaged in POCUS scholarship, and are leaders in POCUS locally and nationally in Canada. The modified Delphi process consisted of three rounds of sequential surveys and discussion to achieve consensus on the top five most influential papers on cardiac POCUS and lung POCUS.

RESULTS

A total of 66 relevant papers on cardiac POCUS and 68 relevant papers on lung POCUS were nominated by the panel. There was 100% participation by the panel members in all three rounds of the modified Delphi process. At the end of this process, we identified the top five most influential papers on cardiac POCUS and lung POCUS. Papers include studies supporting the use of POCUS for accurately assessing left ventricular systolic function, diagnosing pericardial effusion, clarifying its test characteristics for pulmonary embolism, identifying pulmonary edema and pneumonia, as well as consensus statements on the use of cardiac and lung POCUS in clinical practice.

CONCLUSION

We have created a list of the top five influential papers on cardiac POCUS and lung POCUS as an evidence-based resource for trainees, clinicians, and researchers. This will help trainees and clinicians better understand how to use POCUS when scanning the heart and lungs, and it will also help researchers better understand where to direct their scholarly efforts with future research.

The Importance of Lung Ultrasound and IGFBP7 (Insulin-like Growth Factor Binding Protein 7) Assessment in Diagnosing Patients with Heart Failure

Background: In daily practice, there are problems with adequately diagnosing the cause of dyspnea in patients with heart failure with preserved and mildly reduced ejection fractions (HFpEF and HFmrEF). This study aimed to assess the usefulness of lung ultrasound in diagnosing HFpEF and HFmrEF and determine its correlation with IGFBP7 (insulin-like growth factor binding protein 7), NTproBNP (N-terminal pro-B-type natriuretic peptide), and echocardiographic markers. Methods: The research was conducted on 143 patients hospitalized between 2018 and 2020, admitted due to dyspnea, and diagnosed with HFpEF and HFmrEF. Venous blood was collected from all participants to obtain basic biochemical parameters, NTproBNP, and IGFBP7. Moreover, all participants underwent echocardiography and transthoracic lung ultrasound. Two years after hospitalization a follow-up telephone visit was performed. Results: The number of B-lines in the LUS ≥ 16 was determined with a sensitivity of-73% and specificity of-62%, indicating exacerbation of heart failure symptoms on admission. The number of B-lines ≥ 14 on admission was determined as a cut-off point, indicating an increased risk of death during the 2-year follow-up period. The factors that significantly impacted mortality in the study patient population were age and the difference between the number of B-lines on ultrasound at admission and at hospital discharge. IGFBP7 levels had no significant effect on the duration of hospitalization, risk of rehospitalization, or mortality during follow-up. Conclusions: Lung ultrasonography provides additional diagnostic value in patients with HFpEF or HFmrEF and exacerbation of heart failure symptoms. The number of B-lines ≥ 14 may indicate an increased risk of death.

Can non-invasive cardiac hemodynamics and fluid content system (NICaS) parameters predict Acute Heart Failure outcomes in Caucasian and Asian patients in the emergency department?

PURPOSE

Acute heart failure (AHF) is a serious condition that requires prompt diagnosis and management. To optimize patient care, clinicians need a reliable, non-invasive method to assess hemodynamic parameters and total body congestion. Currently, no standardized technology is widely used for this purpose. However, NICaS technology, which measures hemodynamic parameters based on regional bioimpedance, has shown promise in monitoring AHF patients in a non-invasive and reliable manner. In this study, researchers aimed to evaluate the usefulness of NICaS technology in predicting patients' outcome in Caucasian and Asian AHF patients presenting to the emergency department (ED).

PATIENTS AND METHODS

The study included 40 Caucasian patients from Italy (group A) and 71 Asian patients from Indonesia and Singapore (group B) with a diagnosis of AHF in the ED. The study compared data from NICaS parameters, clinical findings, laboratory, and radiological results with short-term events.

RESULTS

In group A, NICaS data at ED arrival significantly predicted 30-day cardiovascular mortality and rehospitalization. At discharge, a value of cardiac output obtained using NICaS was a significant predictor for 30-day rehospitalization. In group B, NICaS variables, total peripheral resistance index on admission and during 48-72 ​h had prominent AUC compared to clinical congestion score and NT-proBNP in predicting mortality and rehospitalization.

CONCLUSIONS

The results indicate that NICaS technology offers a simple, non-invasive, and reliable method of assessing cardiac hemodynamics and congestion in AHF patients. These measurements may enhance diagnosis, tailor management plans, stratify risk, and predict outcomes in both Caucasian and Asian patients.

Comparison of the prognostic value, feasibility, and reproducibility among different scoring methods of 8‑point lung ultrasonography in patients with acute heart failure

There is no strong evidence that one of the B-line quantification approaches is clinically superior to the others, as the use of lung ultrasound (LUS) protocol becomes more commonplace in the treatment of heart failure (HF). This study, thus, aimed to evaluate to the prognostic value, feasibility, and reproducibility for selecting optimal B-line quantification methods. We enrolled patients with HF admitted to the emergency intensive care unit (EICU) in a single-center, prospective, observational study. LUS were performed before EICU discharge, and six B-line quantification methods were used to calculate scores. A total of 71 patients were enrolled. There was a moderately good discriminative value between six quantification methods and the composite outcome. The calibration curve of six B-line quantification methods for the probability of the composite outcome showed good agreement between prediction and observation. Decision curve presented that six B-line quantification methods presented similar net benefits at the entire range of threshold probabilities. Image interpretation time of Quantitative methods 1 and 2 was significantly less than that of other methods. Intraclass correlation coefficients (ICC) for B-pattern scoring systems (Quantitative methods 1 and 2) between two experts demonstrated the excellent level of clinical significance. Despite the similar discrimination, calibration and clinical usefulness, pattern-B scoring systems have the benefit of the feasibility and reproducibility over other methods.

Two- Versus 8-Zone Lung Ultrasound in Heart Failure: Analysis of a Large Data Set Using a Deep Learning Algorithm

OBJECTIVE

Scanning protocols for lung ultrasound often include 8 or more lung zones, which may limit real-world clinical use. We sought to compare a 2-zone, anterior-superior thoracic ultrasound protocol for B-line artifact detection with an 8-zone approach in patients with known or suspected heart failure using a deep learning (DL) algorithm.

METHODS

Adult patients with suspected heart failure and B-lines on initial lung ultrasound were enrolled in a prospective observational study. Subjects received daily ultrasounds with a hand-held ultrasound system using an 8-zone protocol (right and left anterior/lateral and superior/inferior). A previously published deep learning algorithm that rates severity of B-lines on a 0-4 scale was adapted for use on hand-held ultrasound full video loops. Average severities for 8 and 2 zones were calculated utilizing DL ratings. Bland-Altman plot analyses were used to assess agreement and identify bias between 2- and 8-zone scores for both primary (all patients, 5728 videos, 205 subjects) and subgroup (confirmed diagnosis of heart failure or pulmonary edema, 4464 videos, 147 subjects) analyses.

RESULTS

Bland-Altman plot analyses revealed excellent agreement for both primary and subgroup analyses. The absolute difference on the 4-point scale between 8- and 2-zone average scores was not significant for the primary dataset (0.03; 95% CI -0.01 to 0.07) or the subgroup (0.01; 95% CI -0.04 to 0.06).

CONCLUSION

Utilization of a 2-zone, anterior-superior thoracic ultrasound protocol provided similar severity information to an 8-zone approach for a dataset of subjects with known or suspected heart failure.

Acute dyspnea in the emergency department: a clinical review

Acute dyspnea represents one of the most frequent symptoms leading to emergency room evaluation. Its significant prognostic value warrants a careful evaluation. The differential diagnosis of dyspnea is complex due to the lack of specificity and the loose association between its intensity and the severity of the underlying pathological condition. The initial assessment of dyspnea calls for prompt diagnostic evaluation and identification of optimal monitoring strategy and provides information useful to allocate the patient to the most appropriate setting of care. In recent years, accumulating evidence indicated that lung ultrasound, along with echocardiography, represents the first rapid and non-invasive line of assessment that accurately differentiates heart, lung or extra-pulmonary involvement in patients with dyspnea. Moreover, non-invasive respiratory support modalities such as high-flow nasal oxygen and continuous positive airway pressure have aroused major clinical interest, in light of their efficacy and practicality to treat patients with dyspnea requiring ventilatory support, without using invasive mechanical ventilation. This clinical review is focused on the pathophysiology of acute dyspnea, on its clinical presentation and evaluation, including ultrasound-based diagnostic workup, and on available non-invasive modalities of respiratory support that may be required in patients with acute dyspnea secondary or associated with respiratory failure.

Machine Learning Algorithm Detection of Confluent B-Lines

OBJECTIVE

B-lines are a ring-down artifact of lung ultrasound that arise with increased alveolar water in conditions such as pulmonary edema and infectious pneumonitis. Confluent B-line presence may signify a different level of pathology compared with single B-lines. Existing algorithms aimed at B-line counting do not distinguish between single and confluent B-lines. The objective of this study was to test a machine learning algorithm for confluent B-line identification.

METHODS

This study used a subset of 416 clips from 157 subjects, previously acquired in a prospective study enrolling adults with shortness of breath at two academic medical centers, using a hand-held tablet and a 14-zone protocol. After exclusions, random sampling generated a total of 416 clips (146 curvilinear, 150 sector and 120 linear) for review. A group of five experts in point-of-care ultrasound blindly evaluated the clips for presence/absence of confluent B-lines. Ground truth was defined as majority agreement among the experts and used for comparison with the algorithm.

RESULTS

Confluent B-lines were present in 206 of 416 clips (49.5%). Sensitivity and specificity of confluent B-line detection by algorithm compared with expert determination were 83% (95% confidence interval [CI]: 0.77-0.88) and 92% (95% CI: 0.88-0.96). Sensitivity and specificity did not statistically differ between transducers. Agreement between algorithm and expert for confluent B-lines measured by unweighted κ was 0.75 (95% CI: 0.69-0.81) for the overall set.

CONCLUSION

The confluent B-line detection algorithm had high sensitivity and specificity for detection of confluent B-lines in lung ultrasound point-of-care clips, compared with expert determination.

Pulmonary Congestion on Lung Ultrasound Predicts Increased Risk of 30-Day Readmission in Heart Failure Patients

OBJECTIVES

Heart failure exacerbations are a common cause of hospitalizations with a high readmission rate. There are few validated predictors of readmission after treatment for acute decompensated heart failure (ADHF). Lung ultrasound (LUS) is sensitive and specific in the assessment of pulmonary congestion; however, it is not frequently utilized to assess for congestion before discharge. This study assessed the association between number of B-lines, on LUS, at patient discharge and risk of 30-day readmission in patients hospitalized for acute decompensated heart failure (ADHF).

METHODS

This was a single-center prospective study of adults admitted to a quaternary care center with a diagnosis of ADHF. At the time of discharge, the patient received an 8-zone LUS exam to evaluate for the presence of B-lines. A zone was considered positive if ≥3 B-lines was present. We assessed the risk of 30-day readmission associated with the number of lung zones positive for B-lines using a log-binomial regression model.

RESULTS

Based on data from 200 patients, the risk of 30-day readmission in patients with 2-3 positive lung zones was 1.25 times higher (95% CI: 1.08-1.45), and in patients with 4-8 positive lung zones was 1.50 times higher (95% CI: 1.23-1.82, compared with patients with 0-1 positive zones, after adjusting for discharge blood urea nitrogen, creatinine, and hemoglobin.

CONCLUSION

Among patients admitted with ADHF, the presence of B-lines at discharge was associated with a significantly increased risk of 30-day readmission, with greater number of lung zones positive for B-lines corresponding to higher risk.

Feasibility of tele-guided patient-administered lung ultrasound in heart failure

BACKGROUND

Readmission rates for heart failure remain high, and affordable technology for early detection of heart failure decompensation in the home environment is needed. Lung ultrasound has been shown to be a sensitive tool to detect pulmonary congestion due to heart failure, and monitoring patients in their home environment with lung ultrasound could help to prevent hospital admissions. The aim of this project was to investigate whether patient-performed tele-guided ultrasound in the home environment using an ultraportable device is feasible.Affiliations: Journal instruction requires a country for affiliations; however, these are missing in affiliations [1, 2]. Please verify if the provided country are correct and amend if necessary.Correct METHODS: Stable ambulatory patients with heart failure received a handheld ultrasound probe connected to a smart phone or tablet. Instructions for setup were given in person during a clinic visit or over the phone. During each ultrasound session, patients obtained six ultrasound clips from the anterior and lateral chest with verbal and visual tele-guidance from an ultrasound trained clinician. Patients also reported their weight and degree of dyspnea, graded on a 5-point scale. Two independent reviewers graded the ultrasound clips based on the visibility of the pleural line and A or B lines.

RESULTS

Eight stable heart failure patients each performed 10-12 lung ultrasound examinations at home under remote guidance within a 1-month period. There were no major technical difficulties. A total of 89 ultrasound sessions resulted in 534 clips of which 88% (reviewer 1) and 84% (reviewer 2) were interpretable. 91% of ultrasound sessions produced interpretable clips bilaterally from the lateral chest area, which is most sensitive for the detection of pulmonary congestion. The average time to complete an ultrasound session was 5 min with even shorter recording times for the last session. All patients were clinically stable during the study period and no false positive B-lines were observed.

CONCLUSIONS

In this feasibility study, patients were able to produce interpretable lung ultrasound exams in more than 90% of remotely supervised sessions in their home environment. Larger studies are needed to determine whether remotely guided lung ultrasound could be useful to detect heart failure decompensation early in the home environment.

Lung Ultrasound in Coronary Care Unit, an Important Diagnostic Tool for Concomitant Pneumonia

Background: In the setting of a coronary care unit (CCU), the early detection of pneumonia is of paramount important to prevent severe complications. This study was designed aiming to evaluate the diagnostic accuracy of lung ultrasound (LUS) in the detection of pneumonia and compared with chest X-ray (CXR). Method: We enrolled 110 consecutive patients admitted to the CCU of Federico II University Hospital. Each patient underwent CXR and bedside LUS on admission. The final diagnosis (pneumonia vs. no pneumonia) was established by another clinician reviewing clinical and laboratory data independent of LUS results and possibly prescribing chest contrast-enhanced CT (n = 34). Results: The mean age was 70 ± 11 years old, and 68% were males. Pneumonia was clinically diagnosed in 26 (23%) patients. LUS was positive for pneumonia in 24 patients (sensitivity 92%, specificity 81%). Chest radiography was positive for pneumonia in nine patients (sensitivity 43%, specificity 95%). Using CT scan as a reference, LUS exhibited 92% sensitivity and a specificity of 96%. In ROC curve analysis, the diagnostic accuracy of CXR and LUS for the diagnosis of pneumonia was 0.86 (95% CI 0.77−0.94), which was higher than CXR 0.68 (95% CI 0.55−0.84), p < 0.05. Conclusion: Based on the findings of the present study, the accuracy of LUS in the detection of pneumonia was significantly higher than chest X-ray with comparable sensibility to CT scan.

POCUS in dyspnea, nontraumatic hypotension, and shock; a systematic review of existing evidence

BACKGROUND

Point-of-care ultrasound (POCUS) has been adopted as a powerful tool in acute medicine. This systematic review aims to critically appraise the existing literature on point-of-care ultrasound in respiratory or circulatory deterioration.

METHODS

Original studies on POCUS and dyspnea, nontraumatic hypotension, and shock from March 2002 until March 2022 were assessed in the PubMed and Embase Databases. Two reviewers independently screened articles for inclusion, extracted data, and assessed the quality of included studies using an established checklist.

RESULTS

We included 89 articles in this review. Point-of-care ultrasound in the initial workup increases the diagnostic accuracy in patients with dyspnea, nontraumatic hypotension and shock in the ED, ICU and medical ward setting. No improvement is found in patients with severe sepsis in the ICU setting. POCUS is capable of narrowing the differential diagnoses and is faster, and more feasible in the acute setting than other diagnostics available. Results on outcome measures are heterogenous. The quality of the included studies is considered low most of the times, mainly because of performance and selection bias and absence of a gold standard as the reference test.

CONCLUSION

We conclude that POCUS contributes to a higher diagnostic accuracy in dyspnea, nontraumatic hypotension, and shock. It aides in narrowing the differential diagnoses and shortening the time to correct diagnosis and effective treatment.

TRIAL REGISTRY

INPLASY; Registration number: INPLASY202220020; URL: https://inplasy.com/.

Evaluation of a Novel Point-of-Care Ultrasound Curriculum for First-Year Pediatric Residents

OBJECTIVE

The aim of the study is to evaluate a novel point-of-care ultrasound (POCUS) educational curriculum for pediatric residents.

METHODS

The cohort study in graduate medical education was completed from January 2017 to March 2019. Postgraduate year 1 (PGY1) pediatric residents attended the educational curriculum that consisted of 3 half-day sessions over a 3-month period. Each session consisted of a lecture (introduction, extended focused assessment with sonography for trauma, soft tissue/musculoskeletal, cardiac, and resuscitative applications) followed by supervised hands-on scanning sessions. Group ratio was 3 learners to 1 machine/expert instructor. Main outcome measures included pre- and post-written test scores, as well as objective structured clinical examination (OSCE) scores.

RESULTS

Forty-nine PGY1 residents (78% women) completed the curriculum. The mean (SD) pretest score was 68% (8.5), and the mean posttest score was 83% (8.3) with a difference of 15 (95% confidence interval, 12.5-17.6; P < 0.001). Mean (SD) focused assessment with sonography for trauma OSCE score after the curriculum was 88.7% (11.9). The number of PGY1 pediatric residents that were comfortable performing POCUS examinations increased from pretraining to posttraining for soft tissue/musculoskeletal (14%-61%, P < 0.001), extended focused assessment with sonography for trauma (24%-90%, P < 0.001), and cardiac (18%-86%, P < 0.001). All participants found the curriculum useful, and 42 of 49 (86%) stated the curriculum increased their ability to acquire and interpret images.

CONCLUSIONS

Postgraduate year 1 pediatric residents learned the basics of POCUS through 3 brief educational sessions. The increase in posttest scores demonstrated improved POCUS knowledge, and the high OSCE score demonstrated their ability to acquire ultrasound images. Point-of-care ultrasound guidelines are needed for pediatric residency programs.

Interobserver Agreement and Correlation of an Automated Algorithm for B-Line Identification and Quantification With Expert Sonologist Review in a Handheld Ultrasound Device

OBJECTIVES

B-lines are ultrasound artifacts that can be used to detect a variety of pathologic lung conditions. Computer-aided methods to detect and quantify B-lines may standardize quantification and improve diagnosis by novice users. We sought to test the performance of an automated algorithm for the detection and quantification of B-lines in a handheld ultrasound device (HHUD).

METHODS

Ultrasound images were prospectively collected on adult emergency department patients with dyspnea. Images from the first 124 patients were used for algorithm development. Clips from 80 unique subjects for testing were randomly selected in a predefined proportion of B-lines (0 B-lines, 1-2 B-lines, 3 or more B-lines) and blindly reviewed by five experts using both a manual and reviewer-adjusted process. Intraclass correlation coefficient (ICC) and weighted kappa were used to measure agreement, while an a priori threshold of an ICC (3,k) of 0.75 and precision of 0.3 were used to define adequate performance.

RESULTS

ICC between the algorithm and manual count was 0.84 (95% confidence interval [CI] 0.75-0.90), with a precision of 0.15. ICC between the reviewer-adjusted count and the algorithm count was 0.94 (95% CI 0.90-0.96), and the ICC between the manual and reviewer-adjusted counts was 0.94 (95% CI 0.90-0.96). Weighted kappa was 0.72 (95% CI 0.49-0.95), 0.88 (95% CI 0.74-1), and 0.85 (95% CI 0.89-0.96), respectively.

CONCLUSIONS

This study demonstrates a high correlation between point-of-care ultrasound experts and an automated algorithm to identify and quantify B-lines using an HHUD. Future research may incorporate this HHUD in clinical studies in multiple settings and users of varying experience levels.

Diagnostic utility of lung echography for congestive heart failure performed by junior resident doctors

Background

Dyspnea is a high priority symptom in the emergency department, with heart failure (HF) as one of its leading causes. Recently, the “comet tail sign (CTS),” a pulmonary ultrasonographic sign, has been proposed as an efficacious tool for detecting pulmonary edema. However, to the best of our knowledge, there have been no published data regarding its utility when performed by non‐experts, including junior residents.

Methods

Between September 2017 and December 2018, patients with dyspnea, who were admitted to the ER, were enrolled. CTS was evaluated by junior residents at the ER. All patients were evaluated by cardiologists independently, and clinical HF was defined as requiring pharmacological intervention by a cardiologist. At the end of this study, we investigated the results of CTS, laboratory data, and available radiological images.

Results

A total of 95 patients were enrolled in the current study, wherein 42 patients were treated by cardiologists as those with clinical HF. Our results showed that CTS could identify clinical HF with a sensitivity of 71.4% and a specificity of 81.1%. The sensitivity of CTS against brain natriuretic peptide (BNP) (cut‐off value, 100 pg/ml) was calculated at 92.5%. Furthermore, when evaluated together with peripheral edema, CTS identified clinical HF with a sensitivity of 96%. False positives for CTS included bilateral pneumonia, hypoalbuminemia, and interstitial pneumonitis.

Conclusions

Our results indicate that CTS is a simple and effective tool for the use of non‐experts, including junior residents.

Outcomes of Simplified Lung Ultrasound Exam in COVID-19: Implications for Self-Imaging

OBJECTIVES

Lung ultrasound B-lines represent interstitial thickening or edema and relate to mortality in COVID-19. As B-lines can be detected with minimal training using point-of-care ultrasound (POCUS), we examined the frequency, clinical associations, and outcomes of B-lines when found using a simplified POCUS method in acutely ill patients with COVID-19.

METHODS

In this retrospective cohort study, hospital data from COVID-19 patients who had undergone lung imaging during standard echocardiography or POCUS were reviewed for an ultrasound lung comet (ULC) sign, defined as the presence of ≥3 B-lines from images of only the antero-apex of either lung (ULC+). Clinical risk factors, oximetry and radiographic results, and disease severity were analyzed for associations with ULC+. Clinical risk factors and ULC+ were analyzed for associations with hospital mortality or the need for intensive care in multivariable models.

RESULTS

Of N = 160 patients, age (mean ± standard deviation) was 64.8 ± 15.5 years, and 46 (29%) died. ULC+ was present in 100/160 (62%) of patients overall, in 81/103 (79%) of severe-or-greater disease versus 19/57 (33%) of moderate-or-less disease (P < .0001) and was associated with mortality (odds ratio [OR] = 2.4 [95% confidence interval [CI]: 1.1-5.4], P = .02) and the need for intensive care (OR = 5.23 [95% CI: 2.42-12.40], P < .0001). In the multivariable models, symptom duration and severe-or-greater disease were associated with ULC+, and ULC+, diabetes, and symptom duration were associated with the need for intensive care.

CONCLUSIONS

B-lines in the upper chest were common and related to disease severity, intensive care, and hospital mortality in COVID-19. Validation of a simplified lung POCUS exam could provide the evidence basis for a self-imaging application during the pandemic.

The Utility of Maternal Point of Care Ultrasound on Labor and Delivery Wards

Point-of-care ultrasonography (POCUS) refers to limited bedside ultrasound used to evaluate patients for conditions specific to the scope of their practice. Given the benefits of its application, interest in its use is increasing. We aimed to review the literature and assess the potential feasibility of using POCUS of the heart and lungs in the field of obstetrics. We aim to describe its relevance and value as an adjunctive tool for critically ill obstetric patients on labor and delivery wards.

Mapping Trends and Hotspots Regarding the Use of Ultrasound in Emergency Medicine: A Bibliometric Analysis of Global Research

Objective: Diagnostic tools in emergency medicine have been widely studied. As a non-invasive and quick tool, ultrasound plays a role in the field of emergency medicine. Thus, it is significant to understand the global scientific output of this topic. An analysis of publications on the use of ultrasound in emergency medicine over the past decade was performed and summarized to track the current hotspots and highlight future directions.

Methods: Globally relevant publications on ultrasound in emergency medicine from 2009 to 2020 were extracted from the Web of Science collection database. VOSviewer software and CiteSpace were employed to visualize and predict the trends in the research on the topic.

Results: The overall volume of global publications is on the rise; furthermore, the United States published the most publications in this field and had the most citations and H-index. University of California at San Francisco in the United States has most publications in terms of institutions. The American Journal of Emergency Medicine published the most papers related to ultrasound in emergency medicine in terms of journals. Pulmonary embolism was once the main research direction, and importantly, “point-of-care ultrasound” was determined to be a new research hotspot.

Conclusion: Altogether, the number of publications on ultrasound in emergency medicine will rise in the future. In addition, the findings reported here shed new light on the major progress on ultrasound in emergency medicine, which may be mutually cooperative in various fields. Moreover, this bibliometric study provides further indications for the topic of “point-of-care ultrasound”.

Teaching point-of-care transfontanellar ultrasound for pediatricians and medical students

OBJECTIVES

The authors aim to evaluate the "point-of-care" transfontanellar ultrasound (TU) as an extension to pediatric physical examination and suggest a TU teaching protocol.

METHODS

The students were randomly divided into two groups, group A (12 participants) and group B (15 participants). The first group only received theoretical training, while the second group received theoretical and practical training. A third group, group C, included 15 pediatricians and interns who also received theoretical and practical training. All the participants underwent multiple-choice testing before and after a four-hour short course on TU. Six months later, another evaluation was performed to analyze the retained knowledge. Furthermore, a questionnaire based on the Likert scale was administered to evaluate satisfaction.

RESULTS

The cognitive evaluation (maximum score=10 points) before and after training increased in group A from 4,0±1,04 to 7,5±1,2 (p<0.001) and, 6 months later, to 6,5±1,16 (p<0.003); in group B from 3,8±1,24 to 8,8±1,01 (p<0.001) and, 6 months later, to 8,46±0,91 (p<0.001); and in group C from 6,0±0,75 to 9,0±0,75 (p<0.001) and, 6 months later, to 8,8±0,77 (p<0.001). The average satisfaction estimated by the Likert scale was over 80% for all questions.

CONCLUSION

Cognitive assessment before and after classes and training reveals progress in learning, with knowledge retention in 6 months. Theoretical-practical courses are well accepted.

Point-of-Care Ultrasound (POCUS) for the assessment of volume status and fluid management in patients with severe pre-eclampsia: A systematic review and meta-analysis

BACKGROUND AND AIMS

Appropriate volume assessment and fluid management can prevent maternal deaths in the severely pre-eclamptic (SPE) parturients. We planned a systematic review and meta-analysis (MA) to evaluate the role and ability of point-of-care ultrasound (POCUS) in the assessment of volume status and early detection of lung oedema in an SPE parturient.

METHODS

An e-literature search was done from several databases. Data were extracted under five domains including POCUS-derived parameters like echo comet score (ECS), lung ultrasound (LUS) scores, B-patterns, optic nerve sheath diameter (ONSD), E/e' ratio, presence of pleural effusion, pulmonary interstitial syndrome and pulmonary congestion. The risk of bias was assessed. Extracted data were analysed using MetaXL and Revman 5.3. Heterogeneity in the studies was evaluated using the Cochrane Q test and I2 statistics. Funnel plots were used for the assessment of publication bias.

RESULTS

Seven prospective studies including 574 parturients (including 396 pre-eclamptics) were selected. POCUS included lung, optic nerve, cardiac and thoracic US. In two studies, the ECS and LUS scores pre-delivery were higher in pre-eclamptics. Two studies found a mean ONSD of 5-5.84 mm before delivery. MA revealed a significantly lower mean ECS score at post-delivery than pre-delivery, and the summary prevalence of B-pattern and pleural effusion among SPE parturients was found to be 0.28 (0.03-0.84) and 0.1 (0-0.2), respectively. A good correlation was observed between B-line patterns and diastolic dysfunction (increased E/e' ratio), LUS score and thoracic fluid content, ONSD and ECS in individual studies.

CONCLUSION

POCUS parameters can be useful as early markers of fluid status and serve as useful tools in the precise clinical management of pre-eclampsia.

Ultrasound and Influenza: The Spectrum of Lung and Cardiac Ultrasound Findings in Patients with Suspected Influenza A and B

In patients with influenza, cardiac and lung ultrasound may help determine the severity of illness and predict clinical outcomes. To determine the ultrasound characteristics of influenza and define the spectrum of lung and cardiac findings in patients with suspected influenza A or B, we conducted a prospective observational study in patients presenting to the emergency department at a tertiary care academic institution. An ultrasound protocol consisting of cardiac, lung and inferior vena cava scans was performed within 6 h of admission. We compared the ultrasound findings in cases with positive and negative influenza polymerase chain reaction, while controlling for comorbidities. We enrolled 117 patients, 41.9% of whom (49/117) tested positive for influenza. In those with influenza, ultrasound confirmed preserved left ventricular and right ventricular (RV) function in 81.3% of patients. The most common cardiac pathology was RV dilation (10.4%), followed by left ventricular systolic dysfunction (8.3%). Patients with negative influenza polymerase chain reaction with RV dysfunction demonstrated higher hospital admission than those those with normal RV function (45.1%, 23/51, vs. 17.9%, 5/28; p = 0.016). B-lines were prevalent in both influenza and non-influenza groups (40.8% and 69.1%, respectively; p = 0.013). Lung consolidation was identified in only 8.25% of patients with influenza. In conclusion, in patients with influenza we were unable to define distinct ultrasound features specific to influenza A or B, suggesting that ultrasound may not be beneficial in diagnosing influenza nor in evaluating its severity.

Integration of imaging and circulating biomarkers in heart failure: a consensus document by the Biomarkers and Imaging Study Groups of the Heart Failure Association of the European Society of Cardiology

Circulating biomarkers and imaging techniques provide independent and complementary information to guide management of heart failure (HF). This consensus document by the Heart Failure Association (HFA) of the European Society of Cardiology (ESC) presents current evidence-based indications relevant to integration of imaging techniques and biomarkers in HF. The document first focuses on application of circulating biomarkers together with imaging findings, in the broad domains of screening, diagnosis, risk stratification, guidance of treatment and monitoring, and then discusses specific challenging settings. In each section we crystallize clinically relevant recommendations and identify directions for future research. The target readership of this document includes cardiologists, internal medicine specialists and other clinicians dealing with HF patients.

Canadian Internal Medicine Ultrasound (CIMUS) Expert Consensus Statement on the Use of Lung Ultrasound for the Assessment of Medical Inpatients With Known or Suspected Coronavirus Disease 2019

OBJECTIVES

To develop a consensus statement on the use of lung ultrasound (LUS) in the assessment of symptomatic general medical inpatients with known or suspected coronavirus disease 2019 (COVID-19).

METHODS

Our LUS expert panel consisted of 14 multidisciplinary international experts. Experts voted in 3 rounds on the strength of 26 recommendations as "strong," "weak," or "do not recommend." For recommendations that reached consensus for do not recommend, a fourth round was conducted to determine the strength of those recommendations, with 2 additional recommendations considered.

RESULTS

Of the 26 recommendations, experts reached consensus on 6 in the first round, 13 in the second, and 7 in the third. Four recommendations were removed because of redundancy. In the fourth round, experts considered 4 recommendations that reached consensus for do not recommend and 2 additional scenarios; consensus was reached for 4 of these. Our final recommendations consist of 24 consensus statements; for 2 of these, the strength of the recommendations did not reach consensus.

CONCLUSIONS

In symptomatic medical inpatients with known or suspected COVID-19, we recommend the use of LUS to: (1) support the diagnosis of pneumonitis but not diagnose COVID-19, (2) rule out concerning ultrasound features, (3) monitor patients with a change in the clinical status, and (4) avoid unnecessary additional imaging for patients whose pretest probability of an alternative or superimposed diagnosis is low. We do not recommend the use of LUS to guide admission and discharge decisions. We do not recommend routine serial LUS in patients without a change in their clinical condition.

[Update on diagnostics and treatment of heart failure]

Inzidenz und Prävalenz der Herzinsuffizienz steigen weltweit. Trotz zahlreicher wissenschaftlicher und klinischer Innovationen ist sie weiterhin mit einer hohen Morbidität und Mortalität behaftet, sodass eine leitliniengerechte Diagnostik und Therapie von entscheidender Bedeutung sind. Die kardiale Dekompensation zählt zu den häufigsten Aufnahmegründen in deutschen Krankenhäusern. Somit stellt die Behandlung herzinsuffizienter Patienten eine erhebliche Herausforderung für das deutsche Gesundheitssystem dar. Dieser Artikel fasst die neuesten wissenschaftlichen Erkenntnisse zur akuten und chronischen Herzinsuffizienz der Jahre 2018 bis 2020 zusammen.

Lung Ultrasound-Guided Fluid Management versus Standard Care in Surgical ICU Patients: A Randomised Controlled Trial

The value of lung ultrasound (LU) in assessing extravascular lung water (EVLW) was demonstrated by comparing LU with gold-standard methods for EVLW assessment. However, few studies have analysed the value of B-Line score (BLS) in guiding fluid management during critical illness. The purpose of this trial was to evaluate if a BLS-guided fluid management strategy could improve fluid balance and short-term mortality in surgical intensive care unit (ICU) patients. We conducted a randomised, controlled trial within the ICUs of two university hospitals. Critically ill patients were randomised upon ICU admission in a 1:1 ratio to BLS-guided fluid management (active group) or standard care (control group). In the active group, BLS was monitored daily until ICU discharge or day 28 (whichever came first). On the basis of BLS, different targets for daily fluid balance were set with the aim of avoiding or correcting moderate/severe EVLW increase. The primary outcome was 28-day mortality. Over 24 months, 166 ICU patients were enrolled in the trial and included in the final analysis. Trial results showed that daily BLS monitoring did not lead to a different cumulative fluid balance in surgical ICU patients as compared to standard care. Consecutively, no difference in 28-day mortality between groups was found (10.5% vs. 15.6%, p = 0.34). However, at least 400 patients would have been necessary for conclusive results.

Comparison of curvilinear-array (microconvex) and phased-array transducers for ultrasonography of the lungs in dogs

OBJECTIVES

To compare the use of curvilinear-array (microconvex) and phased-array transducers for ultrasonographic examination of the lungs in dogs.

ANIMALS

13 client-owned dogs with left-sided congestive heart failure.

PROCEDURES

In a prospective methods comparison study, 24 ultrasonographic examinations of the lungs (4 sites/hemithorax) were performed with both curvilinear-array and phased-array transducers at 3 clinical time points. Two observers independently assessed the number of B lines (scored per site and in total), number of sites strongly positive for B lines (ie, those with > 3 B lines/site), and image quality (scored on a 5-point scale). Analyses included assessment of interobserver agreement with κ analysis, comparison of quality scores between transducers with mixed-effects modeling, and investigation of agreement and bias for B-line data and quality scores between transducers with Passing-Bablok regression.

RESULTS

Interobserver agreement for total B-line scores and number of strong-positive sites was excellent (κ > 0.80) for both transducers. There was no evidence of analytic bias for the number of B lines or strong-positive sites between transducers. Interobserver agreement for image quality scores was moderate (κ, 0.498 and 0.517 for the curvilinear-array and phased-array transducers, respectively). Both observers consistently assigned higher-quality scores to curvilinear-array images than to phased-array images.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated both curvilinear-array (microconvex) and phased-array transducers can be used by experienced sonographers to obtain diagnostic ultrasonographic images of the lungs in dogs with acute or resolving left-sided congestive heart failure and suggested the former transducer may be preferred, particularly to aid identification of anatomic landmarks for orientation.

Point-of-Care Ultrasonography in Patients With Acute Dyspnea: An Evidence Report for a Clinical Practice Guideline by the American College of Physicians

BACKGROUND

Dyspnea is a common and often debilitating symptom with a complex diagnostic work-up.

PURPOSE

To evaluate the benefits, harms, and diagnostic test accuracy of point-of-care ultrasonography (POCUS) in patients with acute dyspnea. (PROSPERO: CRD42019126419).

DATA SOURCES

Searches of multiple electronic databases without language limitations (January 2004 to August 2020) and reference lists of pertinent articles and reviews.

STUDY SELECTION

Five randomized controlled trials (RCTs) and 44 prospective cohort-type studies in patients with acute dyspnea evaluated POCUS as a diagnostic tool to determine the underlying cause of dyspnea. Two investigators independently screened the literature for inclusion.

DATA EXTRACTION

Data abstraction by a single investigator was confirmed by a second investigator; 2 investigators independently rated risk of bias and determined certainty of evidence.

DATA SYNTHESIS

Point-of-care ultrasonography, when added to a standard diagnostic pathway, led to statistically significantly more correct diagnoses in patients with dyspnea than the standard diagnostic pathway alone. In-hospital mortality and length of hospital stay did not differ significantly between patients who did or did not receive POCUS in addition to standard diagnostic tests. Finally, POCUS consistently improved the sensitivities of standard diagnostic pathways to detect congestive heart failure, pneumonia, pulmonary embolism, pleural effusion, or pneumothorax; specificities increased in most but not all studies.

LIMITATIONS

Most studies assessed diagnostic test accuracy, which has limited utility for clinical decision making. Studies rarely reported on the proportion of indeterminate sonography results, and no evidence is available on adverse health outcomes of false-positive or false-negative POCUS results.

CONCLUSION

Point-of-care ultrasonography can improve the correctness of diagnosis in patients with acute dyspnea.

PRIMARY FUNDING SOURCE

American College of Physicians.

Evaluation of High Altitude Interstitial Pulmonary Edema in Healthy Participants Using Rapid 4-View Lung Ultrasound Protocol During Staged Ascent to Everest Base Camp

INTRODUCTION

Prior research identified possible interstitial pulmonary fluid, concerning for early high altitude pulmonary edema (HAPE), in a large percentage of trekkers above 3000 m using a comprehensive 28-view pulmonary ultrasound protocol. These trekkers had no clinical symptoms of HAPE despite these ultrasound findings. The more common 4-view lung ultrasound protocol (LUP) is accurate in rapidly detecting interstitial edema during resource-rich care. The objective of this study was to evaluate whether the 4-view LUP detects interstitial fluid in trekkers ascending to Everest Base Camp.

METHODS

Serial 4-view LUP was performed on 15 healthy trekkers during a 9-d ascent from Kathmandu to Everest Base Camp. Ascent protocols complied with Wilderness Medical Society guidelines for staged ascent. A 4-view LUP was performed in accordance with the published 2012 international consensus protocols on lung ultrasound. Symptom assessment and 4-view LUP were obtained at 6 waypoints along the staged ascent. A 4-view LUP was positive for interstitial edema if ≥3 B-lines were detected in 2 ultrasound windows.

RESULTS

A single participant had evidence of interstitial lung fluid at 5380 m as defined by the 4-view LUP. There was no evidence of interstitial fluid in any participant below 5380 m. One participant was evacuated for acute altitude sickness at 4000 m but showed no preceding sonographic evidence of interstitial fluid.

CONCLUSIONS

In this small study, sonographic detection of interstitial fluid, suggestive of early HAPE, was not identified by the 4-view LUP protocol.

A practical guide to the lung ultrasound for the assessment of congestive heart failure

Dyspnea is one of the major symptoms encountered in the emergency department, and lung ultrasound (LUS) is recommended for the rapid diagnosis of the underlying disease. B-lines, the "comet-tail"-like vertical lines moving with respiration, are an ultrasound finding relevant to the pulmonary congestion. They may be observed in the normal lung, but bilateral, ≥ 3 B-lines are considered pathological. B-lines with lung sliding (B profile) are a specific sign of heart failure, while B-lines with abolished lung sliding (B' profile) are related with the lung diseases such as acute respiratory distress syndrome. B profile is reported to detect pulmonary edema with about 95% sensitivity and 95% specificity in patients with dyspnea. LUS also can assess the severity of pulmonary congestion semi-quantitatively by counting the number of B-lines or that of positive areas. Whereas the original BLUE protocol requires scanning at 12 zones on the chest, more rapid 8- or 6-zone scan is sufficient for the diagnosis of heart failure, and 2- or 4-zone scan may be used for the critical patients. LUS may be used for the evaluation of heart failure treatment, or can be performed as a part of exercise stress test. LUS can be performed easily and rapidly at the bedside using almost any kind of ultrasound apparatus, and it should be performed more widely in the daily practice as well as in the emergent department.

The Conundrum of Volume Status Assessment: Revisiting Current and Future Tools Available for Physicians at the Bedside

Assessment of patients’ volume status at the bedside is a very important clinical skill that physicians need in many clinical scenarios. Hypovolemia with hypotension and tissue under-perfusion are usually more alarming to physicians, but hypervolemia is also associated with poor outcomes, making euvolemia a crucial goal in clinical practice. Nevertheless, the assessment of volume status can be challenging, especially in the absence of a gold standard test that is reliable and easily accessible to assist with clinical decision-making. Physicians need to have a broad knowledge of the individual non-invasive clinical tools available for them at the bedside to evaluate volume status. In this review, we will discuss the strengths and limitations of the traditional tools, which include careful history taking, physical examination, and basic laboratory tests, and also include the relatively new tool of point-of-care ultrasound.

Bedside lung ultrasonography by emergency department residents as an aid for identifying heart failure in patients with acute dyspnea after a 2-h training course

BACKGROUND

Ultrasonographic B-lines have recently emerged as a bedside imaging tool for the differential diagnosis of acute dyspnea in the Emergency Department (ED). However, despite its simplicity, LUS has not fully penetrated emergency department. This study aimed to assess the accuracy and reproducibility of ultrasonographic B-lines performed by emergency medicine (EM) residents for the diagnosis of congestive heart failure (CHF) in patients admitted to ED for acute dyspnea.

PATIENTS AND METHODS

This is a cross-sectional prospective study conducted between January 2016 and October 2017 including patients aged over 18 years admitted to ED for acute dyspnea. At admission, two consecutive bedside LUS study were performed by a pair of EM residents who received a 2-h course for recognition of sonographic B-lines to determine independently B-lines score and B-profile pattern. All participating sonographers were blinded to patients' clinical data. B-lines score ≥ 15 or a B-profile pattern was considered as suggestive of CHF. The final leading diagnosis was assessed by two expert sonographers, who were blinded to the residents' interpretations, based on clinical findings, chest X-ray, brain natriuretic peptide, cardiac and lung ultrasound testing. Accuracy and agreement of B-lines score and B-profile pattern were calculated.

RESULTS

We included 700 patients with a mean age of 68 ± 12.6 years and a sex ratio (M/F) of 1.43. The diagnosis of CHF was recorded in 371 patients (53%). The diagnostic performance of B-lines score at a cut-off 15 and B-profile pattern was, respectively, 88% and 82.5% for sensitivity, 75% and 84% for specificity, 80% and 85% for positive predictive value, 84% and 81% for negative predictive value. The area under receiver operating characteristic curve was 0.86 [0.83-0.89] and 0.83 [0.80-0.86], respectively, for B-lines score and B-profile pattern. There was an excellent agreement between residents for the diagnosis of CHF using both scores (kappa = 0.81 and 0.85, respectively, for ordinal scale B-lines score and B-profile pattern).

CONCLUSION

Lung ultrasound B-lines assessment has a good accuracy and an excellent reproducibility in the diagnosis of CHF in the hand of EM residents following a short training program. Trial registration Name of the registry: clinicaltrials.gov; Trial registration number: NCT03717779; Date of registration: October 24, 2018 'Retrospectively registered'; URL of trial registry record: clinicaltrials.gov.

Lung Ultrasound vs. Chest X-Ray Study for the Radiographic Diagnosis of COVID-19 Pneumonia in a High-Prevalence Population

Background

The viral illness severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), more commonly known as Coronavirus 2019 (COVID-19), has become a global pandemic, infecting over 100 million individuals worldwide.

Objectives

The objective of this study was to compare the test characteristics of point-of-care lung ultrasound (LUS) with chest x-ray study (CXR) at radiographically detecting COVID-19 pneumonia.

Methods

This was a single-center, prospective, observational study at an urban university hospital with > 105,000 patient visits annually. Patients ≥ 18 years old, who presented to the Emergency Department with predefined signs and symptoms of COVID-19, were eligible for enrollment. Each patient received an LUS using a portable, handheld ultrasound followed by a single-view, portable anteroposterior CXR. Patients with an abnormal LUS or CXR underwent a non-contrast-enhanced computed tomography scan (NCCT). The primary outcome was the radiographic diagnosis of COVID-19 pneumonia on NCCT.

Results

One hundred ten patients underwent LUS, CXR, and NCCT; 99 LUS and 73 CXRs were interpreted as positive; 81 NCCTs were interpreted as positive, providing a prevalence of COVID-19 pneumonia of 75% (95% confidence interval [CI] 66–83.2) in our study population. LUS sensitivity was 97.6% (95% CI 91.6–99.7) vs. 69.9% (95% CI 58.8–79.5) for CXR. LUS specificity was 33.3% (95% CI 16.5–54) vs. 44.4% (95% CI 25.5–64.7) for CXR. LUS positive predictive value and negative predictive value were 81.8% (95% CI 72.8–88.9) and 81.8% (95% CI 48.2–97.7), respectively, vs. 79.5% (95% CI 68.4–88), and 32.4% (95% CI 18–49.8), respectively, for CXR.

Conclusion

LUS was more sensitive than CXR at radiographically identifying COVID-19 pneumonia.

Point-of-care lung ultrasound patterns in late third-trimester gravidas with and without preeclampsia

BACKGROUND

Transthoracic point-of-care ultrasonography of the lungs has become a standard technique in critical care medicine for the evaluation of patients with respiratory signs or symptoms but has not been well studied in pregnancy.

OBJECTIVE

To compare lung ultrasound patterns in third-trimester gravidas with and without preeclampsia and assess interobserver agreement between 3 obstetrical providers and a physician expert in critical care lung ultrasound.

STUDY DESIGN

This is a prospective observational study of 262 women with singleton pregnancies between 32 0/7 and 41 6/7 weeks' gestation. Lung ultrasound examinations were performed and interpreted by a team of obstetrical care providers and then interpreted by an expert in point-of-care lung ultrasound. The number of B-lines in each of the 4 lung fields, indicating the accumulation of fluid in the interstitial space and the alveoli, was evaluated. The primary outcome was a positive study for pulmonary interstitial edema, defined as an ultrasound study with 3 or more B-lines in 2 or more bilateral lung fields. The secondary outcome was a lung ultrasound study with 1 or 2 B-lines in 1 or more lung fields or 3 B-lines in 1 lung field. Interobserver agreement in lung ultrasound interpretation between obstetrical care providers and an expert in critical care point-of-care ultrasonography of the lung was assessed.

RESULTS

Among healthy gravidas, no subject had a lung ultrasound examination positive for pulmonary interstitial edema. Notably, 2 patients with preeclampsia had positive lung ultrasound studies, and both had respiratory symptoms or signs of pulmonary edema. One or 2 B-lines or 3 B-lines in 1 lung field were identified in 11.4% of healthy gravidas and 18.6% of patients with preeclampsia. There was no difference in lung ultrasound patterns between healthy gravidas and those with preeclampsia. The obstetrical care providers and the lung ultrasound expert had a high proportion of agreement regarding the interpretation of negative lung ultrasound examinations. The 2 patients with clinical signs of pulmonary edema were judged to have positive studies by both the obstetrical team and the expert; however, the obstetrical team classified more studies as positive.

CONCLUSION

Lung ultrasound patterns in women with preeclampsia without respiratory symptoms or clinical signs of pulmonary edema are similar to the lung ultrasound patterns of healthy gravidas. Point-of-care lung ultrasound can be used to evaluate third-trimester gravidas with preeclampsia and respiratory complaints or signs concerning for pulmonary edema. Formal training is important before the widespread adoption of point-of-care lung ultrasound by obstetrical healthcare providers.

Utility of point-of-care lung ultrasound for monitoring cardiogenic pulmonary edema in dogs

Background

Point‐of‐care lung ultrasound (LUS) is an effective tool to diagnose left‐sided congestive heart failure (L‐CHF) in dogs via detection of ultrasound artifacts (B‐lines) caused by increased lung water.

Hypothesis/Objectives

To determine whether LUS can be used to monitor resolution of cardiogenic pulmonary edema in dogs, and to compare LUS to other indicators of L‐CHF control.

Animals

Twenty‐five client‐owned dogs hospitalized for treatment of first‐onset L‐CHF.

Methods

Protocolized LUS, thoracic radiographs (TXR), and plasma N‐terminal pro‐B‐type natriuretic peptide were performed at hospital admission, hospital discharge, and recheck examinations. Lung ultrasound findings were compared between timepoints and to other clinical measures of L‐CHF.

Results

From time of hospital admission to discharge (mean 19.6 hours), median number of LUS sites strongly positive for B‐lines (>3 B‐lines per site) decreased from 5 (range, 1‐8) to 1 (range, 0‐5; P < .001), and median total B‐line score decreased from 37 (range, 6‐74) to 5 (range, 0‐32; P = .002). Lung ultrasound indices remained improved at first recheck (P < .001). Number of strong positive sites correlated positively with respiratory rate (r = 0.52, P = .008) and TXR edema score (r = 0.51, P = .009) at hospital admission. Patterns of edema resolution differed between LUS and TXR, with cranial quadrants showing more significant reduction in B‐lines compared to TXR edema score (80% vs 29% reduction, respectively; P = .003).

Conclusions and Clinical Importance

Lung ultrasound could be a useful tool for monitoring resolution of pulmonary edema in dogs with L‐CHF.

Utility of Different Lung Ultrasound Simulation Modalities Used by Paramedics during Varied Ambulance Driving Conditions

INTRODUCTION

Prehospital use of lung ultrasound (LUS) by paramedics to guide the diagnoses and treatment of patients has expanded over the past several years. However, almost all of this education has occurred in a classroom or hospital setting. No published prehospital use of LUS simulation software within an ambulance currently exists.

STUDY OBJECTIVE

The objective of this study was to determine if various ambulance driving conditions (stationary, constant acceleration, serpentine, and start-stop) would impact paramedics' abilities to perform LUS on a standardized patient (SP) using breath-holding to simulate lung pathology, or to perform LUS using ultrasound (US) simulation software. Primary endpoints included the participating paramedics': (1) time to acquiring a satisfactory simulated LUS image; and (2) accuracy of image recognition and interpretation. Secondary endpoints for the breath-holding portion included: (1) the agreement between image interpretation by paramedic versus blinded expert reviewers; and (2) the quality of captured LUS image as determined by two blinded expert reviewers. Finally, a paramedic LUS training session was evaluated by comparing pre-test to post-test scores on a 25-item assessment requiring the recognition of a clinical interpretation of prerecorded LUS images.

METHODS

Seventeen paramedics received a 45-minute LUS lecture. They then performed 25 LUS exams on both SPs and using simulation software, in each case looking for lung sliding, A and B lines, and seashore or barcode signs. Pre- and post-training, they completed a 25-question test consisting of still images and videos requiring pathology recognition and formulation of a clinical diagnosis. Sixteen paramedics performed the same exams in an ambulance during different driving conditions (stationary, constant acceleration, serpentines, and abrupt start-stops). Lung pathology was block randomized based on driving condition.

RESULTS

Paramedics demonstrated improved post-test scores compared to pre-test scores (P <.001). No significant difference existed across driving conditions for: time needed to obtain a simulated image; clinical interpretation of simulated LUS images; quality of saved images; or agreement of image interpretation between paramedics and blinded emergency physicians (EPs). Image acquisition time while parked was significantly greater than while the ambulance was driving in serpentines (Z = -2.898; P = .008). Technical challenges for both simulation techniques were noted.

CONCLUSION

Paramedics can correctly acquire and interpret simulated LUS images during different ambulance driving conditions. However, simulation techniques better adapted to this unique work environment are needed.

Point-of-care Ultrasound in Morbidity and Mortality Cases in Emergency Medicine: Who Benefits the Most?

INTRODUCTION

Point-of-care ultrasound (POCUS) is an essential tool in the timely evaluation of an undifferentiated patient in the emergency department (ED). Our primary objective in this study was to determine the perceived impact of POCUS in high-risk cases presented at emergency medicine (EM) morbidity and mortality (M&M) conferences. Additionally, we sought to identify in which types of patients POCUS might be most useful, and which POCUS applications were considered to be highest yield.

METHODS

This was a retrospective survey of cases submitted to M&M at an EM residency program that spans two academic EDs, over one academic year. Postgraduate year 4 (PGY) residents who presented M&M cases at departmental sessions were surveyed on perceived impacts of POCUS on individual patient outcomes. We evaluated POCUS use and indications while the POCUS was used.

RESULTS

Over the 12-month period, we reviewed 667 cases from 18 M&M sessions by 15 PGY-4 residents and a supervising EM attending physician who chairs the M&M committee. Of these cases, 75 were selected by the M&M committee for review and presentation. POCUS was used in 27% (20/75) of the cases and not used in 73% (55/75). In cases where POCUS was not used, retrospective review determined that if POCUS had been used it would have "likely prevented the M&M" in 45% (25/55). Of these 25 cases, the majority of POCUS applications that could have helped were cardiac (32%, 8/25) and lung (32%, 8/25) ultrasound. POCUS was felt to have greatest potential in identifying missed diagnoses (92%, 23/25), and decreasing the time to diagnosis (92%, 23/25). Patients with cardiopulmonary chief complaints and abnormal vital signs were most likely to benefit. There were seven cases (35%, 7/20, 95% CI 15-59%) in which POCUS was performed and thought to have possibly adversely affected the outcome of the M&M.

CONCLUSION

POCUS was felt to have the potential to reduce or prevent M&M in 45% of cases in which it was not used. Cardiac and lung POCUS were among the most useful applications, especially in patients with cardiopulmonary complaints and in those with abnormal vital signs.

What are the minimum requirements to establish proficiency in lung ultrasound training for quantifying B-lines?

AIMS

The goal of this study was to determine the number of scans needed for novice learners to attain proficiency in B-line quantification compared with expert interpretation.

METHODS AND RESULTS

This was a prospective, multicentre observational study of novice learners, physicians and non-physicians from three academic institutions. Learners received a 2 h lung ultrasound (LUS) training session on B-line assessment, including lecture, video review to practice counting and hands-on patient scanning. Learners quantified B-lines using an eight-zone scanning protocol in patients with suspected acute heart failure. Ultrasound (US) machine settings were standardized to a depth of 18 cm and clip length of 6 s, and tissue harmonics and multibeam former were deactivated. For quantification, the intercostal space with the greatest number of B-lines within each zone was used for scoring. Each zone was given a score of 0-20 based on the maximum number of B-lines counted during one respiratory cycle. The B-line score was determined by multiplying the percentage of the intercostal space filled with B-lines by 20. We compared learner B-line counts with a blinded expert reviewer (five US fellowship-trained faculty with > 5 years of clinical experience) for each lung zone scanned; proficiency was defined as an intraclass correlation of > 0.7. Learning curves for each learner were constructed using cumulative sum method for statistical analysis. The Wilcoxon rank-sum test was used to compare the number of scans required to reach proficiency between different learner types. Twenty-nine learners (21 research associates, 5 residents and 3 non-US-trained emergency medicine faculty) scanned 2629 lung zones with acute pulmonary oedema. After a mean of 10.8 (standard deviation 14.0) LUS zones scanned, learners reached the predefined proficiency standard. The number of scanned zones required to reach proficiency was not significantly different between physicians and non-physicians (P = 0.26), learners with no prior US experience vs. > 25 prior patient scans (P = 0.64) and no prior vs. some prior LUS experience (P = 0.59). The overall intraclass correlation for agreement between learners and experts was 0.74 and 0.80 between experts.

CONCLUSIONS

Our results show that after a short, structured training, novice learners are able to achieve proficiency for quantifying B-lines on LUS after scanning 11 zones. These findings support the use of LUS for B-line quantification by non-physicians in clinical and research applications.

Point-of-care ultrasound modalities in terms of diagnosing acute decompensated heart failure in emergency department; a diagnostic accuracy study

This study aimed to compare the diagnostic accuracy of heart, lung and inferior vena cava (IVC) ultrasonography modalities, alone and combined, for possible added accuracy in diagnosing acute decompensated heart failure (ADHF), in a group of patients with the final diagnosis of ADHF based on plasma level of B-type natriuretic peptide (BNP) as the standard. The present study is a diagnostic accuracy study, which was carried out in the emergency department of Imam Khomeini hospital, affiliated to Tehran University of Medical Sciences, in 2014-2015. All patients over 18 years old, who were referred to emergency department with complaint of acute dyspnea were regarded as eligible and no exclusion criteria were considered. All ultrasounds were performed by a trained emergency medicine resident and then saved and classified for each patient, separately, and reviewed by the attending emergency medicine physician. In this study, patients with BNP levels higher than 500 pg/ml were considered positive for dyspnea caused by heart failure. A total of 120 patients with an average age of 60.83 ± 16.528 years were studied, 64 (53%) of which were male. In total, 47.5% of patients had a BNP level over 500 pg/ml. Among patients with positive ultrasound, 94.7% were true positive and among those with a negative ultrasound, 61.4% were true negative. Based on the findings, B-line ≥ 10 has the highest specificity and left ventricular ejection fraction (LVEF) < 45% has the highest sensitivity. The combination of LVEF and IVC collapsibility index (IVC-CI), LVEF and BLC, IVC-CI and BLC, and IVC-CI and BBPC had a higher specificity rate and combination of LVEF and BBPC and BLC and BBPC had the highest sensitivity. Sensitivity, specificity, positive predictive value and negative predictive value of all three ultrasounds combined were 31.6%, 98.4%, 94.7% and 61.4%, respectively. In this study, the diagnostic accuracy of double and triple ultrasonography of heart, lung and IVC in the diagnosis of ADHF was very high, among which triple ultrasonography was more preferable.

Optimizing B-lines on lung ultrasound: an in-vitro to in-vivo pilot study with clinical implications

B-lines on lung ultrasound (US) are the hallmark of pulmonary edema. It is unknown if ultrasound machine settings or probe type matter. We created an in-vitro gelatin model. Using lung presets as baseline, five blinded investigators assessed the impact of 32 distinct settings on B-line visibility based on a Likert-Scale (LS) from 0 to10 (< 5 worse, > 5 better) separately for two probes. The experiment was then repeated in-vivo in a patient with known pulmonary edema. Based on a multivariable regression LS-ratings were similar when comparing the in-vitro versus in-vivo experiment (P = 0.16; partial R² = 0.2%) and when using the curvilinear versus linear probe (P = 0.69; partial R² = 0.02%) but significantly different across machine settings (P < 0.0001; partial R² = 34.4%). Limited by its pilot character, our study suggests that (1) certain US-machine settings heavily impact B-line visibility, with no clear difference between probes; (2) in-vitro models are a valid and practical alternative to more challenging patient-based research; (3) there is significant potential to improve B-line visibility and thus diagnostic yield in the clinical setting by using lung presets, centering the focal zone at the pleural line and increasing the distal time gain compensation, most of which are (in our experience) rarely done.

Imaging in patients with suspected acute heart failure: timeline approach position statement on behalf of the Heart Failure Association of the European Society of Cardiology

Acute heart failure is one of the main diagnostic and therapeutic challenges in clinical practice due to a non-specific clinical manifestation and the urgent need for timely and tailored management at the same time. In this position statement, the Heart Failure Association aims to systematize the use of various imaging methods in accordance with the timeline of acute heart failure care proposed in the recent guidelines of the European Society of Cardiology. During the first hours of admission the point-of-care focused cardiac and lung ultrasound examination is an invaluable tool for rapid differential diagnosis of acute dyspnoea, which is highly feasible and relatively easy to learn. Several portable and stationary imaging modalities are being increasingly used for the evaluation of cardiac structure and function, haemodynamic and volume status, precipitating myocardial ischaemia or valvular abnormalities, and systemic and pulmonary congestion. This paper emphasizes the central role of the full echocardiographic examination in the identification of heart failure aetiology, severity of cardiac dysfunction, indications for specific heart failure therapy, and risk stratification. Correct evaluation of cardiac filling pressures and accurate prognostication may help to prevent unscheduled short-term readmission. Alternative advanced imaging modalities should be considered to assist patient management in the pre- and post-discharge phase, including cardiac magnetic resonance, computed tomography, nuclear studies, and coronary angiography. The Heart Failure Association addresses this paper to the wide spectrum of acute care and heart failure specialists, highlighting the value of all available imaging techniques at specific stages and in common clinical scenarios of acute heart failure.

Lung Ultrasound for the Cardiologist

For a cardiologist, lung ultrasound is an add-on to transthoracic echocardiography, just as lung auscultation is part of a cardiac physical examination. A cardiac 3.5- to 5.0-MHz transducer is generally suitable because the small footprint makes it ideal for scanning intercostal spaces. The image quality is often adequate, and the lung acoustic window is always patent. The cumulative increase in imaging time is <1 min for the 2 main applications targeted on pleural water (pleural effusion) and lung water (pulmonary congestion as multiple B-lines). In these settings, lung ultrasound outperforms the diagnostic accuracy of the chest radiograph, with a low-cost, portable, real-time, radiation-free method. A "wet lung" detected by lung ultrasound predicts impending acute heart failure decompensation and may trigger lung decongestion therapy. The doctors of tomorrow may still listen with a stethoscope to their patient's lung, but they will certainly be seeing it with ultrasound.

Diagnostic accuracy and temporal impact of ultrasound in patients with dyspnea admitted to the emergency department

OBJECTIVE

Few studies have prospectively evaluated the diagnostic accuracy and temporal impact of ultrasound in the emergency department (ED) in a randomized manner. In this study, we aimed to perform a randomized, standard therapy controlled evaluation of the diagnostic accuracy and temporal impact of a standardized ultrasound strategy, versus standard care, in patients presenting to the ED with acute dyspnea.

METHODS

The patients underwent a standardized ultrasound examination that was blinded to the team caring for the patient. Ultrasound results remained blinded in patients randomized to the treating team but were unblinded in the interventional cohort. Scans were performed by trained emergency physicians. The gold standard diagnosis (GSDx) was determined by two physicians blinded to the ultrasound results. The same two physicians reviewed all data >30 days after the index visit.

RESULTS

Fifty-nine randomized patients were enrolled. The mean±standard deviation age was 54.4±11 years, and 37 (62%) were male. The most common GSDx was acute heart failure with reduced ejection fraction in 13 (28.3%) patients and airway diseases such as acute exacerbation of asthma or chronic obstructive pulmonary disease in 10 (21.7%). ED diagnostic accuracy, as compared to the GSDx, was 76% in the ultrasound cohort and 79% in the standard care cohort (P=0.796). Compared with the standard care cohort, the final diagnosis was obtained much faster in the ultrasound cohort (mean±standard deviation: 12±3.2 minutes vs. 270 minutes, P<0.001).

CONCLUSION

A standardized ultrasound approach is equally accurate, but enables faster ED diagnosis of acute dyspnea than standard care.

Imaging the Injured Lung: Mechanisms of Action and Clinical Use

Acute respiratory distress syndrome (ARDS) consists of acute hypoxemic respiratory failure characterized by massive and heterogeneously distributed loss of lung aeration caused by diffuse inflammation and edema present in interstitial and alveolar spaces. It is defined by consensus criteria, which include diffuse infiltrates on chest imaging-either plain radiography or computed tomography. This review will summarize how imaging sciences can inform modern respiratory management of ARDS and continue to increase the understanding of the acutely injured lung. This review also describes newer imaging methodologies that are likely to inform future clinical decision-making and potentially improve outcome. For each imaging modality, this review systematically describes the underlying principles, technology involved, measurements obtained, insights gained by the technique, emerging approaches, limitations, and future developments. Finally, integrated approaches are considered whereby multimodal imaging may impact management of ARDS.