Is pulmonary hypertension protective against cardiac tamponade? A systematic review.

The presence of pulmonary hypertension (PH) may affect whether cardiac tamponade physiology develops from a pericardial effusion. Specifically, the increased intracardiac pressure and right ventricular hypertrophy associated with PH would seemingly increase the intrapericardial pressure threshold at which the right-sided chambers collapse. In this systematic review, we examined the impact of PH on the incidence, in-hospital and long-term mortality, and echocardiographic findings of patients with cardiac tamponade. Using the PRISMA guideline, a systematic search was conducted in PubMed, Academic Search Premier, Web of Science, Google Scholar, and the Cochrane Database for studies investigating PH and cardiac tamponade. The Newcastle-Ottawa Scale was used to analyze the quality of returned studies. Primary outcomes included the incidence of cardiac tamponade, as well as in-hospital and long-term mortality rates. Secondary outcomes were the presence or absence of echocardiographic findings of cardiac tamponade in patients with PH. Forty-three studies (9 cohort studies and 34 case reports) with 1054 patients were included. The incidence of cardiac tamponade was significantly higher in patients with PH compared to those without PH, 2.0% (95% CI 1.2-3.2%) vs. 0.05% (95% CI 0.05-0.05%), p < 0.0001, OR 40.76 (95% CI 24.8-66.9). The incidence of tamponade in patients with a known pericardial effusion was similar in those with and without PH, 20.3% (95% CI 12.0-32.3%) and 20.9% (95% CI 18.0-24.1%), p = 0.9267, OR 0.97 (95% CI 0.50-1.87). In patients with tamponade, those with PH demonstrated a significantly higher in-hospital mortality than those without PH, 38.8% (95% CI 26.4-52.8%) vs. 14.4% (95% CI 14.2-14.6%), p < 0.0001, OR 3.77 (95% CI 2.12-6.70). Long-term mortality in patients with tamponade was significantly lower in those with PH than in those without PH, 45.5% (95% CI 33.0-58.5%) vs. 59.1% (95% CI 54.7-63.4%), p = 0.0258, OR 0.576 (95% CI 0.33-1.01). However, after stratifying by non-malignant etiologies, the long-term mortality benefit for those with PH disappeared. In the studies that described specific echocardiographic findings of cardiac tamponade, only 10.5% of patients with PH and tamponade showed right atrial and right ventricular collapse. When evaluating patients with pericardial effusions, physicians must recognize the effects of underlying PH on the incidence, in-hospital and long-term mortality rates, and potentially atypical echocardiographic presentation of cardiac tamponade.

A Novel Tool for Predicting an Abnormal Echocardiogram in Patients with Pulmonary Embolism: The PEACE Score.

BACKGROUND: Transthoracic echocardiography (TTE) is an essential tool for risk-stratifying patients with pulmonary embolism (PE), but its availability is limited, often requiring hospitalization. Minimal research exists evaluating clinical and laboratory criteria to predict lack of abnormal TTE findings. OBJECTIVE: We aimed to identify predictors associated with abnormal TTE results in patients with PE to potentially identify those safe for early discharge. METHODS: In this retrospective study, we analyzed an existing database of patients with venous thromboembolism (VTE) at two academic emergency departments, including adult patients with confirmed PE who underwent TTE. The primary goal was to develop and validate a score predicting abnormal TTE, defined as presence of one of the following: right ventricle (RV) dilatation or hypokinesis, septal flattening, right heart thrombus in transit, or ejection fraction < 50%. Variables were demographic characteristics, symptoms, computed tomography (CT) RV strain, troponin T, and N-terminal prohormone of brain natriuretic peptide (NTproBNP). Stepwise logistic regression was used to identify variables independently associated with abnormal TTE. Model discrimination was evaluated using area under the curve (AUC) of the receiver operating characteristic curve. A clinical prediction rule was developed. RESULTS: 530 of 2235 patients were included; 56% (297 of 530) had an abnormal TTE. The following six variables were independently associated with abnormal TTE: dyspnea, dizziness, troponin T ≥ 0.1 ng/mL, NTproBNP > 900 pg/mL, CT RV strain, and nonsubsegmental PE. A clinical prediction rule using these six criteria yielded scores between 0 and 7, performing well with AUC of 0.80 (95% CI 0.79-0.80). A score of 1 was 99.7% sensitive in identifying no abnormality. A score ≥ 5 was 98% specific for an abnormality. CONCLUSIONS: The PEACE (Pulmonary Embolism and Abnormal Cardiac Echocardiogram) criteria, composed of six variables, is highly effective in predicting abnormal TTE in patients with PE, potentially identifying who is safe for early discharge from the hospital.

Handheld Lung Ultrasound to Detect COVID-19 Pneumonia in Inpatients: A Prospective Cohort Study.

Background: Chest imaging, including chest X-ray (CXR) and computed tomography (CT), can be a helpful adjunct to nucleic acid test (NAT) in the diagnosis and management of Coronavirus Disease 2019 (COVID-19). Lung point of care ultrasound (POCUS), particularly with handheld devices, is an imaging alternative that is rapid, highly portable, and more accessible in low-resource settings. A standardized POCUS scanning protocol has been proposed to assess the severity of COVID-19 pneumonia, but it has not been sufficiently validated to assess diagnostic accuracy for COVID-19 pneumonia. Purpose: To assess the diagnostic performance of a standardized lung POCUS protocol using a handheld POCUS device to detect patients with either a positive NAT or a COVID-19-typical pattern on CT scan. Methods: Adult inpatients with confirmed or suspected COVID-19 and a recent CT were recruited from April to July 2020. Twelve lung zones were scanned with a handheld POCUS machine. Images were reviewed independently by blinded experts and scored according to the proposed protocol. Patients were divided into low, intermediate, and high suspicion based on their POCUS score. Results: Of 79 subjects, 26.6% had a positive NAT and 31.6% had a typical CT pattern. The receiver operator curve for POCUS had an area under the curve (AUC) of 0.787 for positive NAT and 0.820 for a typical CT. Using a two-point cutoff system, POCUS had a sensitivity of 0.90 and 1.00 compared to NAT and typical CT pattern, respectively, at the lower cutoff; it had a specificity of 0.90 and 0.89 compared to NAT and typical CT pattern at the higher cutoff, respectively. Conclusions: The proposed lung POCUS protocol with a handheld device showed reasonable diagnostic performance to detect inpatients with a positive NAT or typical CT pattern for COVID-19. Particularly in low-resource settings, POCUS with handheld devices may serve as a helpful adjunct for persons under investigation for COVID-19 pneumonia.

Point-of-care AI-assisted stepwise ultrasound pneumothorax diagnosis.

Objective. Ultrasound is extensively utilized as a convenient and cost-effective method in emergency situations. Unfortunately, the limited availability of skilled clinicians in emergency hinders the wider adoption of point-of-care ultrasound. To overcome this challenge, this paper aims to aid less experienced healthcare providers in emergency lung ultrasound scans.Approach. To assist healthcare providers, it is important to have a comprehensive model that can automatically guide the entire process of lung ultrasound based on the clinician's workflow. In this paper, we propose a framework for diagnosing pneumothorax using artificial intelligence (AI) assistance. Specifically, the proposed framework for lung ultrasound scan follows the steps taken by skilled physicians. It begins with finding the appropriate transducer position on the chest to locate the pleural line accurately in B-mode. The next step involves acquiring temporal M-mode data to determine the presence of lung sliding, a crucial indicator for pneumothorax. To mimic the sequential process of clinicians, two DL models were developed. The first model focuses on quality assurance (QA) and regression of the pleural line region-of-interest, while the second model classifies lung sliding. To achieve the inference on a mobile device, a size of EfficientNet-Lite0 model was further reduced to have fewer than 3 million parameters.Main results. The results showed that both the QA and lung sliding classification models achieved over 95% in area under the receiver operating characteristic (AUC), while the ROI performance reached 89% in the dice similarity coefficient. The entire stepwise pipeline was simulated using retrospective data, yielding an AUC of 89%.Significance. The step-wise AI framework for the pneumothorax diagnosis with QA offers an intelligible guide for each clinical workflow, which achieved significantly high precision and real-time inferences.

Deoxycholic Acid for Dercum Disease: Repurposing a Cosmetic Agent to Treat a Rare Disease.

Dercum disease is a rare condition characterized by multiple painful fatty tumors distributed throughout the body. There currently are no US Food and Drug Administration-approved treatments for Dercum disease, and the treatments tried have shown little to no efficacy, leaving many patients with a profoundly negative impact on quality of life. We present a case series of 3 patients who were diagnosed with Dercum disease and were treated with deoxycholic acid (DCA), a therapy approved for adipolysis of submental fat. The patients experienced a reduction in tumor size with radiographic evidence as well as a notable reduction in symptoms.

Point-of-Care Ultrasound in Children With Medical Complexity.

BACKGROUND AND OBJECTIVES: Children with medical complexity (CMC) have significant chronic health conditions that involve congenital or acquired multisystem disease associated with medical fragility, functional limitations, dependence on technology, and high health care utilization. The objective of this study was to describe the indications, applications, and point-of-care ultrasound (POCUS) findings in this population. METHODS: A descriptive study of POCUS scans performed for clinical purposes in CMC admitted to a single pediatric postacute care hospital. All children for whom a POCUS was requested by a medical team provider were eligible for inclusion. RESULTS: One hundred and four POCUS evaluations were performed for 33 patients. Diagnostic groups for the 33 patients included multiple congenital anomalies (41%), neurologic or neuromuscular (31%), prematurity (25%) and cardiac (3%). Lung, cardiac, and diaphragmatic ultrasound accounted for 57% of POCUS requested. POCUS was abnormal in 82% of diaphragmatic, 73% of lung, and 11% of cardiac ultrasounds. Twenty-three percent of POCUS studies were requested to answer a specific clinical question, 56% for follow-up information, and 21% for baseline evaluation. CONCLUSIONS: Lung, diaphragmatic, and cardiac ultrasound were the most prevalent POCUS studies requested in a postacute care hospital. POCUS may offer an expanded role in such patients and settings by answering clinical questions and by providing baseline and follow-up information.

Effect of the Extended Focused Assessment With Sonography for Trauma on the Screening Performance of the National Emergency X-Radiography Utilization Study Chest Decision Instrument.

STUDY OBJECTIVE: Developed to decrease unnecessary thoracic computed tomography use in adult blunt trauma patients, the National Emergency X-Radiography Utilization Study (NEXUS) Chest clinical decision instrument does not include the extended Focused Assessment with Sonography in Trauma (eFAST). We assessed whether eFAST improves the NEXUS Chest clinical decision instrument's diagnostic performance and may replace the chest radiograph (CXR) as a predictor variable. METHODS: We performed a secondary analysis of prospective data from 8 Level I trauma centers from 2011-2014. We compared performance of modified clinical decision instruments that (1) added eFAST as a predictor (eFAST-added clinical decision instrument), and (2) replaced CXR with eFAST (eFAST-replaced clinical decision instrument), in screening for blunt thoracic injuries. RESULTS: One thousand nine hundred fifty-seven patients had documented computed tomography, CXR, clinical NEXUS criteria, and adequate eFAST; 624 (31.9%) patients had blunt thoracic injuries, and 126 (6.4%) had major injuries. Compared to the NEXUS Chest clinical decision instrument, the eFAST-added clinical decision instrument demonstrated unchanged screening performance for major injury (sensitivity 0.98 [0.94 to 1.00], specificity 0.28 [0.26 to 0.30]) or any injury (sensitivity 0.97 [0.95 to 0.98], specificity 0.21 [0.19 to 0.23]). The eFAST-replaced clinical decision instrument demonstrated unchanged sensitivity for major injury (sensitivity 0.93 [0.87 to 0.97], specificity 0.31 [0.29 to 0.34]) and decreased sensitivity for any injury (0.93 [0.91 to 0.951] versus 0.97 [0.953 to 0.98]). CONCLUSION: In our secondary analysis, adding eFAST as a predictor variable did not improve the diagnostic screening performance of the original NEXUS Chest clinical decision instrument; eFAST cannot replace the CXR criterion of the NEXUS Chest clinical decision instrument.

Accuracy of "TICS" ultrasound protocol in detecting simple and complicated diverticulitis: A prospective cohort study.

BACKGROUND: Point-of-care ultrasound (US) has been suggested as the primary imaging in evaluating patients with suspected diverticulitis. Discrimination between simple and complicated diverticulitis may help to expedite emergent surgical consults and determine the risk of complications. This study aimed to: (1) determine the accuracy of an US protocol (TICS) for diagnosing diverticulitis in the emergency department (ED) setting and (2) assess the ability of TICS to distinguish between simple and complicated diverticulitis. METHODS: Patients with clinically suspected diverticulitis who underwent a diagnostic computed tomography (CT) scan were identified prospectively in the ED. Emergency US faculty and fellows blinded to the CT results performed and interpreted US scans. The presence of simple or complicated diverticulitis was recorded after each US evaluation. The diagnostic ability of the US was compared to CT as the criterion standard. Modified Hinchey classification was used to distinguish between simple and complicated diverticulitis. RESULTS: A total of 149 patients (55% female, mean ± SD age 58 ± 16 years) were enrolled and included in the final analyses. Diverticulitis was the final diagnosis in 75 of 149 patients (50.3%), of whom 53 had simple diverticulitis and 22 had perforated diverticulitis (29.4%). TICS protocol's test characteristics for simple diverticulitis include a sensitivity of 95% (95% confidence interval [CI] 87%-99%), specificity of 76% (95% CI 65%-86%), positive predictive value of 80% (95% CI 71%-88%), and negative predictive value of 93% (95% CI 84%-98%). TICS protocol correctly identified 12 of 22 patients with complicated diverticulitis (sensitivity 55% [95% CI 32%-76%]) and specificity was 96% (95% CI 91%-99%). Eight of 10 missed diagnoses of complicated diverticulitis were identified as simple diverticulitis, and two were recorded as negative. CONCLUSIONS: In ED patients with suspected diverticulitis, US demonstrated high accuracy in ruling out or diagnosing diverticulitis, but its reliability in differentiating complicated from simple diverticulitis is unsatisfactory.

Point-of Care Ultrasound in Stratifying Clinically Evolving Inguinal and Femoral Hernias.

BACKGROUND: Point-of-care ultrasound (POCUS) is an optimal imaging modality for the risk stratification of patients presenting to the emergency department (ED) with inguinal and femoral hernias, allowing for better evaluation of clinical presentations and guiding appropriate treatment. The lack of ultrasound classification for inguinal and femoral hernias has led to inconsistent use and often underuse of POCUS in this patient population. Several groin hernia classifications are available, but most are complex and often targeted toward surgical management. OBJECTIVES: The objective of this study is to review the use of POCUS in the diagnosis of inguinal and femoral hernias, providing a synopsis of critical ultrasound findings in determining signs of incarceration, strangulation, and small bowel obstruction, and suggesting a simple and educative sonographic classification for inguinal or femoral hernias. DISCUSSION: POCUS can reliably confirm the presence of groin hernias and can uniquely identify specific ultrasound findings predictive of complications, such as aperistaltic nonreducible bowel loops, free fluid in the hernia sac, and lack of color doppler in the entrapped mesentery and bowel walls. POCUS can also aid in determining the presence of small bowel obstruction by detecting dilated loops of bowel >25 mm adjacent and proximal to the hernia site. CONCLUSIONS: In the ED, POCUS can confirm the presence of a hernia sac and identify and predict surgical emergencies, such as bowel incarceration or strangulation, which are the most important elements in the management of patients presenting with possible inguinal or femoral hernias.

Optimizing Lung Ultrasound: The Effect of Depth, Gain and Focal Position on Sonographic B-Lines.

Ultrasonographic B-lines are artifacts present in alveolar-interstitial syndromes. We prospectively investigated optimal depth, gain, focal position and transducer type for B-line visualization and image quality. B-Lines were assessed at a single rib interspace with curvilinear and linear transducers. Video clips were acquired by changing parameters: depth (6, 12, 18 and 24 cm for curvilinear transducer, 4 and 8 cm for linear transducer), gain (10%, 50% and 90%) and focal position (at the pleural line or half the scanning depth). Clips were scored for B-lines and image quality. Five hundred sixteen clips were obtained and analyzed. The curvilinear transducer improved B-line visualization (63% vs. 37%, p < 0.0001), with higher image quality (3.52 ± 0.71 vs. 3.31 ± 0.86, p = 0.0047) compared with the linear transducer. B-Lines were better visualized at higher gains (curvilinear: gain of 50% vs. 10%, odds ratio = 7.04, 95% confidence interval: 4.03-12.3; gain of 90% vs. 10%, odds ratio = 9.48, 95% confidence interval: 5.28-17.0) and with the focal point at the pleural line (odds ratio = 1.64, 95% confidence interval: 1.02-2.63). Image quality was highest at 50% gain (p = 0.02) but decreased at 90% gain (p < 0.0001) and with the focal point at the pleural line (p < 0.0001). Image quality was highest at depths of 12-18 cm. B-Lines are best visualized using a curvilinear transducer with at least 50% gain and focal position at the pleural line. Gain less than 90% and image depth between 12 and 18 cm improve image quality.

Point-of-care ultrasound-first for the evaluation of small bowel obstruction: National cost savings, length of stay reduction, and preventable radiation exposure.

OBJECTIVES: Computed tomography (CT) has long been the gold standard in diagnosing patients with suspected small bowel obstruction (SBO). Recently, point-of-care ultrasound (POCUS) has demonstrated comparable test characteristics to CT imaging for the diagnosis of SBO. Our primary objective was to estimate the annual national cost saving impact of a POCUS-first approach for the evaluation of SBO. Our secondary objectives were to estimate the reduction in radiation exposure and emergency department (ED) length of stay (LOS). METHODS: We created and ran 1000 trials of a Monte Carlo simulation. The study population included all patients presenting to the ED with abdominal pain who were diagnosed with SBO. Using this simulation, we modeled the national annual cost savings in averted advanced imaging from a POCUS-first approach for SBO. The model assumes that all patients who require surgery or have non-diagnostic POCUS exams undergo CT imaging. The model also conservatively assumes that a subset of patients with diagnostic POCUS exams undergo additional confirmatory CT imaging. We used the same Monte Carlo model to estimate the reduction in radiation exposure and total ED bed hours saved. RESULTS: A POCUS-first approach for diagnosing SBO was estimated to save a mean (±SD) of $30.1 million (±8.9 million) by avoiding 143,000 (±31,000) CT scans. This resulted in a national cumulative decrease of 507,000 bed hours (±268,000) in ED LOS. The reduction in radiation exposure to patients could potentially prevent 195 (±56) excess annual cancer cases and 98 (±28) excess annual cancer deaths. CONCLUSIONS: If adopted widely and used consistently, a POCUS-first algorithm for SBO could yield substantial national cost savings by averting advanced imaging, decreasing ED LOS, and reducing unnecessary radiation exposure in patients. Clinical decision tools are needed to better identify which patients would most benefit from CT imaging for SBO in the ED.

Point-of-Care Lung Ultrasound for Differentiating COVID-19 From Influenza.

Background and objectives Patients infected with influenza and COVID-19 exhibit similar clinical presentations; thus, a point-of-care test to differentiate between the diseases is needed. Here, we sought to identify features of point-of-care lung ultrasound (LUS) that can discriminate between influenza and COVID-19. Methods In this prospective, cross-sectional study, LUS clips of patients presenting to the emergency department (ED) with viral-like symptoms were collected via a 10-zone scanning protocol. Deidentified clips were interpreted by emergency ultrasound fellows blinded to patients' clinical context and influenza or COVID-19 diagnosis. Modified Soldati scores were calculated for each lung zone. Logistic regression identified the association of pulmonary pathologies with each disease. Results Ultrasound fellows reviewed LUS clips from 165 patients, of which 30.9% (51/165) had confirmed influenza, 33.9% (56/165) had confirmed COVID-19, and 35.1% (58/165) had neither disease. Patients with COVID-19 were more likely to have irregular pleura and B-lines in all lung zones (p<0.01). The median-modified Soldati score for influenza patients was 0/20 (IQR 0-2), 9/20 (IQR 2.5-15.5) for COVID-19 patients, and 2/20 (IQR 0-8) for patients with neither disease (p<0.0001). In multivariate regression analysis adjusted for age, sex, and congestive heart failure (CHF), the presence of B-lines (OR = 1.29, 95% CI 1.09-1.53) was independently associated with COVID-19 diagnosis. The presence of pleural effusion was inversely associated with COVID-19 (OR = 0.09, 95% CI 0.01-0.65). Conclusions LUS may help providers preferentially identify the presence of influenza versus COVID-19 infection both visually and by calculating a modified Soldati score. Further studies assessing the utility of LUS in differentiating viral illnesses in patients with variable illness patterns and those with variable illness severity are warranted.

Advanced practice providers proficiency-based model of ultrasound training and practice in the ED.

Competency in the application of point-of-care ultrasound (POCUS) has come to be an expected fundamental skill set for advanced practice providers (APPs) in the emergency department. Both American College of Emergency Physicians and the Society of Emergency Medicine Physician Assistants approve of and endorse POCUS use by APPs. However, clinical exposure to and practice of ultrasound in this setting is often variable and without structure. POCUS training must be evolved into a system where developed skills are compatible with clinical need and expectations of APPs. At our institution, we developed a formal, structured POCUS training program for emergency medicine (EM) APPs (including physician assistants and nurse practitioners) and evaluated its efficacy quantitatively by means of a proficiency index. This report examines the EM POCUS training most common to physician assistants and nurse practitioners before practicing at our institution and explores the components of our POCUS training program that have affected program development.

Perineural Dexamethasone as a Peripheral Nerve Block Adjuvant in the Emergency Department: A Case Series.

BACKGROUND: Acute pain is one of the most common complaints encountered in the emergency department (ED). Single-injection peripheral nerve blocks are a safe and effective pain management tool when performed in the ED. Dexamethasone has been explored as an adjuvant to prolong duration of analgesia from peripheral nerve blocks in peri- and postoperative settings; however, data surrounding the use of dexamethasone for ED-performed nerve blocks are lacking. CASE SERIES: In this case series we discuss our experience with adjunctive perineural dexamethasone in ED-performed regional anesthesia. Why Should an Emergency Physician be Aware of This?: Nerve blocks performed with adjuvant perineural dexamethasone may be a safe additive to provide analgesia beyond the expected half-life of local anesthetic alone. Prospective studies exploring the role of adjuvant perineural dexamethasone in ED-performed nerve blocks are needed. © 2021 Elsevier Inc.

The Use of Angle-Independent M-Mode in the Evaluation of Diaphragmatic Excursion: Towards Improved Accuracy.

Assessment of diaphragmatic function has been well described in the intensive care setting as well as in emergency medicine and pediatrics. Conventional M-mode evaluation of diaphragmatic excursion is frequently associated with over and under-estimations of diaphragmatic excursion. Angle-independent M-mode allows free rotation and movement of the analysis line to obtain M-mode images in a direction that more accurately reflects diaphragmatic excursion. In order to provide a standardized approach to the evaluation of diaphragmatic excursion with angle-independent M-mode, we propose a landmark-based approach utilizing the spine in order to target the same diaphragmatic segment consistently throughout the diaphragmatic analysis. While the proposed approach is not intended to replace current methods, it may improve accuracy and inter-rater reliability. The relevant background, as well as three patient cases, are presented demonstrating the use of a landmark-based approach in the emergency department. Angle-independent M-mode may provide a more accurate and consistent evaluation of diaphragmatic excursion, an examination that can be used to guide clinical care and anticipate outcomes.

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.

Longitudinal accuracy analysis of ultrasound performed during a four-year emergency medicine residency.

BACKGROUND: The objective of this study was to analyze patterns of point-of-care ultrasound (POCUS) performance over 4 years of emergency medicine (EM) residency. Specifically, we aimed to study how accuracy and adherence to standards of scanning changed by postgraduate year (PGY). METHODS: This was a retrospective observational study of resident-performed POCUS at an academic emergency department over 6 years. We reviewed records of POCUS scans performed by PGY-1 to -4 residents that had been collected for quality assurance purposes. Data that were collected about EM residents' performance included the total number and type of scans per year, rate of technically limited scans (TLS), and accuracy on interpreting ultrasound images. Resident performances in each year (PGY-1 to -4) were independently evaluated and reported. RESULTS: During a 6-year period, 137 different EM residents performed 50,815 ultrasound scans. The median number of scans was 177 for PGY-1, 124 for PGY-2, 118 for PGY-3, and 76 for residents in PGY-4. The accuracy of scan interpretations were high across all PGY levels (>97%), but slight degradation was observed as residents progressed through residency. The TLS rate increased from 4.7% among PGY-1s to 13.6% as PGY-4s. CONCLUSIONS: In this large cohort of POCUS studies by EM residents, POCUS accuracy rates decreased and rates of TLS significantly increased as residents progressed through residency.