Diagnostic accuracy of prehospital lung ultrasound for acute decompensated heart failure: A systematic review and Meta-analysis.

BACKGROUND: Lung ultrasound (LUS) reduces time to diagnosis and treatment of acute decompensated heart failure (ADHF) in emergency department (ED) patients with undifferentiated dyspnea. We conducted a systematic review to evaluate the diagnostic accuracy and clinical impact of LUS for ADHF in the prehospital setting. METHODS: We performed a keyword search of multiple databases from inception through June 1, 2023. Included studies were those enrolling prehospital patients with undifferentiated dyspnea or suspected ADHF, and specifically diagnostic studies comparing prehospital LUS to a gold standard and intervention studies with a non-US comparator group. Title and abstract screening, full text review, risk of bias (ROB) assessments, and data extraction were performed by multiple authors. and adjudicated. The primary outcome was pooled sensitivity, specificity, and diagnostic likelihood ratios (LR) for prehospital LUS. A test-treatment threshold of 0.7 was applied based on prior ADHF literature in the ED. Intervention outcomes included mortality, mechanical ventilation, and time to HF specific treatment. RESULTS: Eight diagnostic studies (n = 691) and two intervention studies (n = 70) met inclusion criteria. No diagnostic studies were low-ROB. Both intervention studies were critical-ROB, and not pooled. Pooled sensitivity and specificity of prehospital LUS for ADHF were 86.7% (95%CI:70.8%-94.6%) and 87.5% (78.2%-93.2%), respectively, with similar performance by physician vs. paramedic LUS and number of lung zones evaluated. Pooled LR+ and LR- were 7.27 (95% CI: 3.69-13.10) and 0.17 (95% CI: 0.06-0.34), respectively. Area under the summary receiver operating characteristic curve was 0.922. At the observed 42.4% ADHF prevalence (pre-test probability), positive pre-hospital LUS exceeded the 70% threshold to initiate treatment (post-test probability 84%, 80-88%). CONCLUSIONS: LUS had similar diagnostic test characteristics for ADHF diagnosis in the prehospital setting as in the ED. A positive prehospital LUS may be sufficient to initiate early ADHF treatment based on published test-treatment thresholds. More studies are needed to determine the clinical impact of prehospital LUS.

Artificial Intelligence-Augmented Pediatric Lung POCUS: A Pilot Study of Novice Learners.

OBJECTIVE: Respiratory symptoms are among the most common chief complaints of pediatric patients in the emergency department (ED). Point-of-care ultrasound (POCUS) outperforms conventional chest X-ray and is user-dependent, which can be challenging to novice ultrasound (US) users. We introduce a novel concept using artificial intelligence (AI)-enhanced pleural sweep to generate complete panoramic views of the lungs, and then assess its accuracy among novice learners (NLs) to identify pneumonia. METHODS: Previously healthy 0- to 17-year-old patients presenting to a pediatric ED with cardiopulmonary chief complaint were recruited. NLs received a 1-hour training on traditional lung POCUS and the AI-assisted software. Two POCUS-trained experts interpreted the images, which served as the criterion standard. Both expert and learner groups were blinded to each other's interpretation, patient data, and outcomes. Kappa was used to determine agreement between POCUS expert interpretations. RESULTS: Seven NLs, with limited to no prior POCUS experience, completed examinations on 32 patients. The average patient age was 5.53 years (±1.07). The median scan time of 7 minutes (minimum-maximum 3-43; interquartile 8). Three (8.8%) patients were diagnosed with pneumonia by criterion standard. Sensitivity, specificity, and accuracy for NLs AI-augmented interpretation were 66.7% (confidence interval [CI] 9.4-99.1%), 96.5% (CI 82.2-99.9%), and 93.7% (CI 79.1-99.2%). The average image quality rating was 2.94 (±0.16) out of 5 across all lung fields. Interrater reliability between expert sonographers was high with a kappa coefficient of 0.8. CONCLUSION: This study shows that AI-augmented lung US for diagnosing pneumonia has the potential to increase accuracy and efficiency.

The Parasternal Long Axis View in Isolation: Is it Good Enough?

BACKGROUND: Focused cardiac ultrasound (FOCUS) is a vital tool to evaluate patients at the bedside, but its use can be limited by patient habitus, sonographer skill, and time to perform the examination. OBJECTIVE: Our primary goal was to determine the diagnostic accuracy of the parasternal long axis (PSLA) view in isolation for identifying pericardial effusion, left ventricular (LV) dysfunction, and right ventricular (RV) dilatation compared with a four-view FOCUS examination. METHODS: This was a retrospective study looking at FOCUS images. Examinations were blinded and randomized for review by point-of-care ultrasound faculty. The primary objective was measured by comparing ultrasound findings on PSLA view in isolation with findings on a full four-view FOCUS examination, which served as the criterion standard. Sensitivity and specificity were calculated. RESULTS: Of 100 FOCUS examinations; 36% were normal, 16% had a pericardial effusion, 41% had an LV ejection fraction < 50%, and 7% had RV dilatation. Sensitivity and specificity for identifying pericardial effusion, LV dysfunction, and RV dilatation were 81% (confidence interval [CI] 0.54-0.95) and 98% (95% CI 0.91-0.99), 100% (95% CI 0.88-1) and 91% (95% CI 0.80-0.97), and 71% (95% CI 0.30-0.94) and 99% (95% CI 0.93-1), respectively. All moderate to large effusions were identified correctly. Overall, there were only four clinically significant disagreements between PSLA alone and the four-view interpretations. CONCLUSIONS: In isolation, the PSLA view was highly sensitive and specific for identifying LV ejection fraction and moderate to large pericardial effusions. It was highly specific for identifying RV dilatation, but had only moderate sensitivity.

Risk factors associated with hospital admission in COVID-19 patients initially admitted to an observation unit.

BACKGROUND: No set guidelines to guide disposition decisions from the emergency department (ED) in patients with COVID-19 exist. Our goal was to determine characteristics that identify patients at high risk for adverse outcomes who may need admission to the hospital instead of an observation unit. METHODS: We retrospectively enrolled 116 adult patients with COVID-19 admitted to an ED observation unit. We included patients with bilateral infiltrates on chest imaging, COVID-19 testing performed, and/or COVID-19 suspected as the primary diagnosis. The primary outcome was hospital admission. We assessed risk factors associated with this outcome using univariate and multivariable logistic regression. RESULTS: Of 116 patients, 33 or 28% (95% confidence interval [CI] 20-37%) required admission from the observation unit. On multivariable logistic regression analysis, we found that hypoxia defined as room-air oxygen saturation < 95% (OR 3.11, CI 1.23-7.88) and bilateral infiltrates on chest radiography (OR 5.57, CI 1.66-18.96) were independently associated with hospital admission, after adjusting for age. Two three-factor composite predictor models, age > 48 years, bilateral infiltrates, hypoxia, and Hispanic race, bilateral infiltrates, hypoxia yield an OR for admission of 4.99 (CI 1.50-16.65) with an AUC of 0.59 (CI 0.51-0.67) and 6.78 (CI 2.11-21.85) with an AUC of 0.62 (CI 0.54-0.71), respectively. CONCLUSIONS: Over 1/4 of suspected COVID-19 patients admitted to an ED observation unit ultimately required admission to the hospital. Risk factors associated with admission include hypoxia, bilateral infiltrates on chest radiography, or the combination of these two factors plus either age > 48 years or Hispanic race.

High rate of isolated right ventricular dysfunction in patients with non-significant CT pulmonary angiography.

BACKGROUND: Right ventricular (RV) dysfunction and pulmonary hypertension (PH) are commonly unrecognized in the emergency department (ED), but are associated with poor outcomes. Prior research has found a 30% prevalence of isolated RV dysfunction in ED patients after non-significant computed tomographic pulmonary angiography (CTPA). We aimed to prospectively define the prevalence of RV dysfunction and/or PH in short of breath ED patients, and assess outcomes. METHODS: Prospective observational study of patients with a non-significant CTPA. Isolated RV dysfunction and/or PH was defined as normal left ventricular function plus RV dilation, moderate to severe tricuspid regurgitation or RV systolic pressure>40mmHg on comprehensive echocardiography. RESULTS: Of 83 patients, 20 (24%, 95% [confidence interval] CI: 16-34%) had isolated RV dysfunction and/or PH. These patients had 40% ED recidivism and 30% hospital readmission at 30-days. When compared to patients with normal echocardiographic function, they had significantly longer intensive care unit and hospital length of stays. CONCLUSIONS: In a prospective cohort of ED patients, we found a high prevalence of isolated RV dysfunction and/or PH after a non-significant CTPA. These patients had high rates of recidivism and hospital readmission. This data supports a continued need for ED based screening and specialty referral.

A Modified Lung and Cardiac Ultrasound Protocol Saves Time and Rules in the Diagnosis of Acute Heart Failure.

BACKGROUND: Multiorgan ultrasound (US), which includes evaluation of the lungs and heart, is an accurate method that outperforms clinical gestalt for diagnosing acutely decompensated heart failure (ADHF). A known barrier to ultrasound use is the time needed to perform these examinations. OBJECTIVE: The primary goal of this study was to determine the test characteristics of a modified lung and cardiac US (LuCUS) protocol for the accurate diagnosis of ADHF. METHODS: This was a secondary analysis of a prospective observational study that enrolled adult patients presenting to the emergency department with undifferentiated dyspnea. Intervention consisted of a modified LuCUS protocol performed by experienced emergency physician sonographers. A positive modified LuCUS protocol was defined as the presence of B+ lines in both the left and right anterosuperior lung zones, plus a left ventricular ejection fraction <45%. If all three of these findings were not present, the modified LuCUS result was interpreted as negative for ADHF. The primary objective was measured by comparing US findings to final diagnosis independently determined by two physicians, both blinded to US findings and each other's final diagnosis. RESULTS: We analyzed data on 99 patients; 36% had a final diagnosis of ADHF. The sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of the modified LuCUS protocol are 25% (95% confidence interval [CI] 14-41%), 100% (95% CI 94-100%), undefined, and 0.75 (95% CI 0.62-0.91%), respectively. This modified protocol takes on average 1 min and 32 sec to complete. CONCLUSION: The point estimate for the specificity of the modified LuCUS protocol in this pilot study, accomplished by a reanalysis of data collected for a previously reported investigation of the full LuCUS protocol, was 100% for the diagnosis of ADHF.

Can emergency physicians diagnose and correctly classify diastolic dysfunction using bedside echocardiography?

OBJECTIVES: The goal of this study was to determine if emergency physicians (EPs) can correctly perform a bedside diastology examination (DE) and correctly grade the level of diastolic function with minimal additional training in echocardiography beyond what is learned in residency. We hypothesize that EPs will be accurate at detecting and grading diastolic dysfunction (DD) when compared to a criterion standard interpretation by a cardiologist. METHODS: We conducted a prospective, observational study on a convenience sample of adult patients who presented to an urban emergency department with a chief concern of dyspnea. All patients had a bedside echocardiogram, including a DE, performed by an EP-sonographer who had 3 hours of didactic and hands-on echocardiography training with a cardiologist. The DE was interpreted as normal, grade 1 to 3 if DD was present, or indeterminate, all based on predefined criteria. This interpretation was compared to that of a cardiologist who was blinded to the EPs' interpretations. RESULTS: We enrolled 62 patients; 52% had DD. Using the cardiology interpretation as the criterion standard, the sensitivity and specificity of the EP-performed DE to identify clinically significant diastolic function were 92% (95% confidence interval [CI], 60-100) and 69% (95% CI, 50-83), respectively. Agreement between EPs and cardiology on grade of DD was assessed using κ and weighted κ: κ = 0.44 (95% CI, 0.29-0.59) and weighted κ = 0.52 (95% CI, 0.38-0.67). Overall, EPs rated 27% of DEs as indeterminate, compared with only 15% by cardiology. For DEs where both EPs and cardiology attempted an interpretation (indeterminates excluded) κ = 0.45 (95% CI, 0.26 to 0.65) and weighted κ = 0.54 (95% CI, 0.36-0.72). CONCLUSION: After limited diastology-specific training, EPs are able to accurately identify clinically significant DD. However, correct grading of DD, when compared to a cardiologist, was only moderate, at best. Our results suggest that further training is necessary for EPs to achieve expertise in grading DD.

Independent evaluation of a simple clinical prediction rule to identify right ventricular dysfunction in patients with shortness of breath.

BACKGROUND: Many patients have unexplained persistent dyspnea after negative computed tomographic pulmonary angiography (CTPA). We hypothesized that many of these patients have isolated right ventricular (RV) dysfunction from treatable causes. We previously derived a clinical decision rule (CDR) for predicting RV dysfunction consisting of persistent dyspnea and normal CTPA, finding that 53% of CDR-positive patients had isolated RV dysfunction. Our goal is to validate this previously derived CDR by measuring the prevalence of RV dysfunction and outcomes in dyspneic emergency department patients. METHODS: A secondary analysis of a prospective observational multicenter study that enrolled patients presenting with suspected PE was performed. We included patients with persistent dyspnea, a nonsignificant CTPA, and formal echo performed. Right ventricular dysfunction was defined as RV hypokinesis and/or dilation with or without moderate to severe tricuspid regurgitation. RESULTS: A total of 7940 patients were enrolled. Two thousand six hundred sixteen patients were analyzed after excluding patients without persistent dyspnea and those with a significant finding on CTPA. One hundred ninety eight patients had echocardiography performed as standard care. Of those, 19% (95% confidence interval [CI], 14%-25%) and 33% (95% CI, 25%-42%) exhibited RV dysfunction and isolated RV dysfunction, respectively. Patients with isolated RV dysfunction or overload were more likely than those without RV dysfunction to have a return visit to the emergency department within 45 days for the same complaint (39% vs 18%; 95% CI of the difference, 4%-38%). CONCLUSION: This simple clinical prediction rule predicted a 33% prevalence of isolated RV dysfunction or overload. Patients with isolated RV dysfunction had higher recidivism rates and a trend toward worse outcomes.

Prehospital lung ultrasound in acute heart failure: Impact on diagnosis and treatment.

OBJECTIVE: Patients with acute heart failure (AHF) are commonly misdiagnosed and undertreated in the prehospital setting. These delays in diagnosis and treatment have a direct negative impact on patient outcomes. The goal of this study was to determine the diagnostic accuracy of paramedics with and without the use of lung ultrasound (LUS) for the diagnosis of AHF in patients with dyspnea in the prehospital setting. Secondarily, we assessed LUS impact on rate of and time to initiation of HF therapies. METHODS: This was a prospective interventional study on a consecutive sample of patients transported to the hospital by one emergency medical services agency. Adult patients (>18 years) with a chief complaint of dyspnea were included. LUS was performed by trained paramedics and was defined as positive for AHF if both anterior-superior lung zones had greater than or equal to three B-lines or bilateral B-lines were visualized on a four-view protocol. Paramedic diagnosis was compared to hospital discharge diagnosis which served as the criterion standard. RESULTS: Of the 264 included patients, 94 (35%) had a final diagnosis of AHF. Forty total patients had a LUS performed; 17 of these patients had a final diagnosis of AHF. Sensitivity and specificity for AHF by paramedics were 23% (95% confidence interval [CI] 0.14-0.34) and 97% (95% CI 0.92-0.99) without LUS and 71% (95% CI 0.44-0.88) and 96% (95% CI 0.76-0.99) with the use of LUS. In the 94 patients with AHF, 14% (11/77) received HF therapy prehospital without the use of LUS and 53% (9/17) with the use of LUS. LUS improved frequency of treatment by 39%. Median time to treatment was 21 min with LUS and 169 min without. CONCLUSIONS: LUS improved paramedic sensitivity and accuracy for diagnosing AHF in the prehospital setting. LUS use led to higher rates of prehospital HF therapy initiation and significantly decreased time to treatment.

The prognostic value of improving congestion on lung ultrasound during treatment for acute heart failure differs based on patient characteristics at admission.

BACKGROUND: Lung ultrasound congestion scoring (LUS-CS) is a congestion severity biomarker. The BLUSHED-AHF trial demonstrated feasibility for LUS-CS-guided therapy in acute heart failure (AHF). We investigated two questions: 1) does change (∆) in LUS-CS from emergency department (ED) to hospital-discharge predict patient outcomes, and 2) is the relationship between in-hospital decongestion and adverse events moderated by baseline risk-factors at admission? METHODS: We performed a secondary analysis of 933 observations/128 patients from 5 hospitals in the BLUSHED-AHF trial receiving daily LUS. ∆LUS-CS from ED arrival to inpatient discharge (scale -160 to +160, where negative = improving congestion) was compared to a primary outcome of 30-day death/AHF-rehospitalization. Cox regression was used to adjust for mortality risk at admission [Get-With-The-Guidelines HF risk score (GWTG-RS)] and the discharge LUS-CS. An interaction between ∆LUS-CS and GWTG-RS was included, under the hypothesis that the association between decongestion intensity (by ∆LUS-CS) and adverse outcomes would be stronger in admitted patients with low-mortality risk but high baseline congestion. RESULTS: Median age was 65 years, GWTG-RS 36, left ventricular ejection fraction 36 %, and ∆LUS-CS -20. In the multivariable analysis ∆LUS-CS was associated with event-free survival (HR = 0.61; 95 % CI: 0.38-0.97), while discharge LUS-CS (HR = 1.00; 95%CI: 0.54-1.84) did not add incremental prognostic value to ∆LUS-CS alone. As GWTG-RS rose, benefits of LUS-CS reduction attenuated (interaction p < 0.05). ∆LUS-CS and event-free survival were most strongly correlated in patients without tachycardia, tachypnea, hypotension, hyponatremia, uremia, advanced age, or history of myocardial infarction at ED/baseline, and those with low daily loop diuretic requirements. CONCLUSIONS: Reduction in ∆LUS-CS during AHF treatment was most associated with improved readmission-free survival in heavily congested patients with otherwise reassuring features at admission. ∆LUS-CS may be most useful as a measure to ensure adequate decongestion prior to discharge, to prevent early readmission, rather than modify survival.

Evaluation of Point-of-Care Ultrasound Training for Family Physicians Using Teleultrasound.

BACKGROUND AND OBJECTIVES: The goal of this study was to assess family physicians' change in knowledge and ability to perform abdominal aorta ultrasound after implementation of a novel teleultrasound curriculum. METHODS: This was a prospective, observational study conducted at a single academic institution. Family physicians completed a preassessment, test, and objective structured clinical evaluation (OSCE). Physicians then individually completed a standard curriculum consisting of online content and an hour-long, hands-on training session on abdominal aorta ultrasound using teleultrasound technology. Physicians then performed a minimum of 10 independent examinations over a period of 8 weeks. After physicians completed the training curriculum and 10 independent scans, we administered a postassessment, test, and OSCE. We analyzed differences between pre- and postcurriculum responses using Fisher exact and Wilcoxon signed rank tests. RESULTS: Thirteen family physicians completed the curriculum. Comparing pre- to postcurriculum responses, we found significant reductions in barriers to using aorta POCUS and improved confidence in using, obtaining, and interpreting aorta POCUS (P<0.01). Knowledge improved from a median score of 70% to 90% (P<0.01), and OSCE scores improved from a median of 80% to 100% (P=0.012). Overall, 211 aorta ultrasound examinations were independently acquired with a median image quality of 4 (scale 1 to 4). CONCLUSIONS: After an 8-week teleultrasound curriculum, family physicians with minimal experience with POCUS showed improved knowledge and psychomotor skill in abdominal aorta POCUS.

Bedside lung ultrasound for the diagnosis of pneumonia in children presenting to an emergency department in a resource-limited setting.

BACKGROUND: Lung ultrasound (LUS) is an effective tool for diagnosing pneumonia; however, this has not been well studied in resource-limited settings where pneumonia is the leading cause of death in children under 5 years of age. OBJECTIVE: The objective of this study was to evaluate the diagnostic accuracy of bedside LUS for diagnosis of pneumonia in children presenting to an emergency department (ED) in a resource-limited setting. METHODS: This was a prospective cross-sectional study of children presenting to an ED with respiratory complaints conducted in Nepal. We included all children under 5 years of age with cough, fever, or difficulty breathing who received a chest radiograph. A bedside LUS was performed and interpreted by the treating clinician on all children prior to chest radiograph. The criterion standard was radiographic pneumonia, diagnosed by a panel of radiologists using the Chest Radiography in Epidemiological Studies methodology. The primary outcome was sensitivity and specificity of LUS for the diagnosis of pneumonia. All LUS images were later reviewed and interpreted by a blinded expert sonographer. RESULTS: Three hundred and sixty-six children were enrolled in the study. The median age was 16.5 months (IQR 22) and 57.3% were male. Eighty-four patients (23%) were diagnosed with pneumonia by chest X-ray. Sensitivity, specificity, positive and negative likelihood ratios for clinician's LUS interpretation was 89.3% (95% CI 81-95), 86.1% (95%CI 82-90), 6.4, and 0.12 respectively. LUS demonstrated good diagnostic accuracy for pneumonia with an area under the curve of 0.88 (95% CI 0.83-0.92). Interrater agreement between clinician and expert ultrasound interpretation was excellent (k = 0.85). CONCLUSION: Bedside LUS when used by ED clinicians had good accuracy for diagnosis of pneumonia in children in a resource-limited setting.

External validation of the ultrasound competency assessment tool.

Objective: Point-of-care ultrasound (POCUS) is a core component of emergency medicine (EM) residency training. No standardized competency-based tool has gained widespread acceptance. The ultrasound competency assessment tool (UCAT) was recently derived and validated. We sought to externally validate the UCAT in a 3-year EM residency program. Methods: This was a convenience sample of PGY-1 to -3 residents. Utilizing the UCAT and an entrustment scale, as described in the original study, six different evaluators split into two groups graded residents in a simulated scenario involving a patient with blunt trauma and hypotension. Residents were asked to perform and interpret a focused assessment with sonography in trauma (FAST) examination and apply the findings to the simulated scenario. Demographics, prior POCUS experience, and self-assessed competency were collected. Each resident was evaluated simultaneously by three different evaluators with advanced ultrasound training utilizing the UCAT and entrustment scales. Intraclass correlation coefficient (ICC) between evaluators was calculated for each assessment domain; analysis of variance was used to compare UCAT performance and PGY level and prior POCUS experience. Results: Thirty-two residents (14 PGY-1, nine PGY-2, and nine PGY-3) completed the study. Overall, ICC was 0.9 for preparation, 0.57 for image acquisition, 0.3 for image optimization, and 0.46 for clinical integration. There was moderate correlation between number of FAST examinations performed and entrustment and UCAT composite scores. There was poor correlation between self-reported confidence and entrustment and UCAT composite scores. Conclusions: We had mixed results in our attempt to externally validate the UCAT with poor correlation between faculty and moderate to good correlation with faculty to diagnostic sonographer. More work is needed to validate the UCAT before adoption.

Gamification of POCUS: Are Students Learning?

INTRODUCTION: While gamification of point-of-care ultrasound (POCUS) is well received by learners, little is known about the knowledge gained from material taught during these events. We set out to determine whether a POCUS gamification event improved knowledge of interpretation and clinical integration of POCUS. METHODS: This was a prospective observational study of fourth-year medical students who participated in a 2.5-hour POCUS gamification event consisting of eight objective-oriented stations. Each station had one to three learning objectives associated with the content taught. Students completed a pre-assessment; they then participated in the gamification event in groups of three to five per station and subsequently completed a post-assessment. Differences between pre- and post-session responses were matched and analyzed using Wilcoxon signed-rank test and Fisher's exact test. RESULTS: We analyzed data from 265 students with matched pre- and post-event responses; 217 (82%) students reported no to little prior POCUS experience. Most students were going into internal medicine (16%) and pediatrics (11%). Knowledge assessment scores significantly improved from pre- to post-workshop, 68% vs 78% (P=0.04). Self-reported comfort with image acquisition, interpretation, and clinical integration all significantly improved from pre- to post-gamification event (P<0.001). CONCLUSION: In this study we found that gamification of POCUS, with clear learning objectives, led to improved student knowledge of POCUS interpretation, clinical integration, and self-reported comfort with POCUS.

Comparison of pulmonary congestion severity using artificial intelligence-assisted scoring versus clinical experts: A secondary analysis of BLUSHED-AHF.

AIM: Acute decompensated heart failure (ADHF) is the leading cause of cardiovascular hospitalizations in the United States. Detecting B-lines through lung ultrasound (LUS) can enhance clinicians' prognostic and diagnostic capabilities. Artificial intelligence/machine learning (AI/ML)-based automated guidance systems may allow novice users to apply LUS to clinical care. We investigated whether an AI/ML automated LUS congestion score correlates with expert's interpretations of B-line quantification from an external patient dataset. METHODS AND RESULTS: This was a secondary analysis from the BLUSHED-AHF study which investigated the effect of LUS-guided therapy on patients with ADHF. In BLUSHED-AHF, LUS was performed and B-lines were quantified by ultrasound operators. Two experts then separately quantified the number of B-lines per ultrasound video clip recorded. Here, an AI/ML-based lung congestion score (LCS) was calculated for all LUS clips from BLUSHED-AHF. Spearman correlation was computed between LCS and counts from each of the original three raters. A total of 3858 LUS clips were analysed on 130 patients. The LCS demonstrated good agreement with the two experts' B-line quantification score (r = 0.894, 0.882). Both experts' B-line quantification scores had significantly better agreement with the LCS than they did with the ultrasound operator's score (p < 0.005, p < 0.001). CONCLUSION: Artificial intelligence/machine learning-based LCS correlated with expert-level B-line quantification. Future studies are needed to determine whether automated tools may assist novice users in LUS interpretation.

Prehospital Diagnosis and Treatment of Patients With Acute Heart Failure.

Introduction  Early diagnosis and optimization of heart failure therapies in patients with acute heart failure (AHF), including in the prehospital setting, is crucial to improving outcomes. However, making the diagnosis of AHF in the prehospital setting is difficult. The goal of this study was to evaluate the accuracy of prehospital diagnosis (AHF versus not heart failure [HF]) in patients with acute dyspnea when compared to final hospital diagnosis. Methods We conducted a retrospective study of adult patients transported by emergency medical services (EMS) with a primary or secondary complaint of shortness of breath. Patients were identified through an EMS electronic database (ESO) and matched to their hospital encounter. ESO was reviewed for prehospital diagnosis and management. Hospital electronic medical records were reviewed to determine final hospital diagnosis, management in the emergency department and hospital, disposition, and length of stay. The primary outcome compared prehospital diagnosis to final hospital diagnosis, which served as our criterion standard. Results Of 199 included patients, 50 (25%) had a final diagnosis of AHF. Prehospital paramedic sensitivity and accuracy for AHF were 14% (7/50; confidence interval [CI] 0.06-0.26) and 77% (CI 0.70-0.82), respectively. In the 50 patients with AHF, 14 (28%) received nitroglycerin in the prehospital setting, while 27 (54.0%) patients were inappropriately treated with albuterol. Conclusion Prehospital paramedics had poor sensitivity and moderate accuracy for the diagnosis of AHF. A small percentage of patients ultimately diagnosed with AHF had HF therapy initiated in the prehospital setting. This data highlights the fact that AHF is difficult to diagnose in the prehospital setting and is commonly missed.

The State of Point-of-Care Ultrasound Training in Undergraduate Medical Education: Findings From a National Survey.

PURPOSE: The primary aim of this study was to evaluate the current state of point-of-care ultrasound (POCUS) integration in undergraduate medical education (UME) at MD-granting medical schools in the United States. METHOD: In 2020, 154 clinical ultrasound directors and curricular deans at MD-granting medical schools were surveyed. The 25-question survey collected data about school characteristics, barriers to POCUS training implementation, and POCUS curriculum details. Descriptive analysis was conducted using frequency and percentage distributions. RESULTS: One hundred twenty-two (79%) of 154 schools responded to the survey, of which 36 were multicampus. Sixty-nine (57%) schools had an approved POCUS curriculum, with 10 (8%) offering a longitudinal 4-year curriculum. For a majority of schools, POCUS instruction was required during the first year (86%) and second year (68%). Forty-two (61%) schools were teaching fundamentals, diagnostic, and procedural ultrasound. One hundred fifteen (94%) schools identified barriers to implementing POCUS training in UME, which included lack of trained faculty (63%), lack of time in current curricula (54%), and lack of equipment (44%). Seven (6%) schools identified no barriers. CONCLUSIONS: Over half of the responding medical schools in the United States had integrated POCUS instruction into their UME curricula. Despite this, a very small portion had a longitudinal curriculum and multiple barriers existed for implementation, with the most common being lack of trained faculty. The data from this study can be used by schools planning to add or expand POCUS instruction within their current curricula.

Assessment of Medical Students' Ability to Integrate Point-of-Care Cardiac Ultrasound Into a Case-Based Simulation After a Short Intervention.

INTRODUCTION: While a large amount of point-of-care ultrasound (POCUS) undergraduate medical education research exists, very little assesses the effectiveness of teaching on the student's ability to utilize POCUS within a clinical context. We set out to assess the ability of pre-clinical (second year) medical students to perform and interpret a parasternal long axis (PSLA) cardiac ultrasound view, and to diagnose a pericardial effusion on POCUS in a simulated patient with hypotension. METHODS: This was a prospective study assessing second-year medical students before and after focused cardiac POCUS instruction. Pre-instruction, students completed a pre-assessment and test. They then watched a short video on cardiac ultrasound technique, anatomy, and pathology. Students then participated in 10 minutes of one-on-one hands-on instruction using a simulated patient. Immediately after didactics and hands-on instruction, students in groups of two to four completed a case simulation where they performed a PSLA view, identified pathology, and made a diagnosis. Differences between pre- and post-workshop responses were analyzed using the Chi-square test. RESULTS: We analyzed data on 132 pre-clinical second-year medical students; 126 (95%) had limited to no POCUS experience prior to the workshop. Comparing pre- to post-workshop responses, we found significant improvement in students' ability to identify a pericardial effusion (46% to 69%) (p=0.002) on a PSLA cardiac view. Of the 57 student groups (132 students), 41 (72%) groups were able to adequately obtain a PSLA view on a mannequin using an ultrasound simulator without needing guidance with probe placement or maneuvering. Thirty-five (61%) student groups were able to identify a pericardial effusion and diagnose cardiac tamponade in a simulated patient with hypotension. CONCLUSION: After short, structured training, pre-clinical medical students, novice to cardiac POCUS, showed improved knowledge with identifying a pericardial effusion on an ultrasound image. The majority of students were able to obtain a PSLA view and diagnose cardiac tamponade in a hypotensive patient during a during a case-based simulation.

Point-of-Care Ultrasound Education During a Pandemic: From Webinar to Progressive Dinner-Style Bedside Learning.

OBJECTIVE: Point-of-care ultrasound (POCUS), traditionally, requires the proximity of learners and educators, making POCUS education challenging during the COVID-19 pandemic. We set out to evaluate three alternate approaches to teaching POCUS in UME. Sessions progressed from an online seminar to a remote, interactive simulation to a "progressive dinner" style session, as precautions evolved throughout the pandemic. METHODS: This prospective study details a series of three POCUS workshops that were designed to align with prevailing social distancing precautions during the COVID-19 pandemic. Overall, 656 medical students were included. The first and second workshops used web-based conferencing technology with real-time ultrasound imaging, with the second workshop focusing on clinical integration through simulation. As distancing precautions were updated, a novel "progressive dinner" technique was used for the third workshop. Surveys were conducted after each session to obtain feedback on students' attitudes toward alternative teaching techniques and quantitative and qualitative analyses were used. RESULTS: The initial, remote POCUS workshop was performed for 180 medical students. Ninety-nine (177) percent of students felt the session was "intellectually challenging" and "stimulating." Ninety-nine percent of students (340/344), after the second workshop, indicated the session was intellectually challenging, stimulating, and a positive learning experience. Students' ability to correctly identify pathologic images increased post-session evaluation from in-session polling. For workshop three, 99% (107/108) of students indicated that the session was "informative." There was a significant improvement in pre- to post-workshop knowledge regarding image acquisition, interpretation, and clinical integration. CONCLUSION: While image acquisition skills are best conveyed at the bedside, these modified POCUS teaching techniques developed and delivered in alignment with COVID-19 pandemic restrictions during a series of three workshops were shown to be effective surrogates for traditional teaching approaches when social distancing requirements, a large learner pool, or lack of local expertise exist.