Documenting the Growth of Ultrasound Research in Emergency Medicine Through a Bibliometric Analysis of Accepted Academic Conference Abstracts.

OBJECTIVES: Ultrasound (US) has become an indispensable skill for emergency physicians. Growth in the use of US in emergency medicine (EM) has been characterized by practice guidelines, education requirements, and the number of EM US practitioners. Our purpose was to further document the growth of EM US by profiling the breadth, depth, and quality of US-related research presented at EM's most prominent annual research conference: the Society for Academic Emergency Medicine Annual Meeting. METHODS: We reviewed published research abstracts from the annual Society for Academic Emergency Medicine conferences from 1999 to 2015. Abstracts related to US were identified and examined for the number of authors and rigor of the research design. Designs were categorized as experimental, quasiexperimental, and nonexperimental. Abstract submissions were analyzed by the average rate of change over time. RESULTS: From 1999 to 2015, we observed a 10.2% increase in the number of accepted abstracts related to US research. This rate compared to a 3.2% average rate of change for all abstracts in general. The number of unique authors engaged in US research increased at a rate of 26.6%. Of the 602 abstracts identified as US related, only 12% could be considered experimental research. CONCLUSIONS: We observed larger increases in the number of US-related research relative to the total number of abstracts presented at a national conference. The number of investigators engaging in this research has also steadily increased. The research design of these studies was found to be primarily quasiexperimental. To improve the quality of EM's use of point-of-care US, more rigorous research with experimental designs is needed.

Hypertrophic Cardiomyopathy in Youth Athletes: Successful Screening With Point-of-Care Ultrasound by Medical Students.

OBJECTIVES: Hypertrophic cardiomyopathy (HCM) is a life-threatening genetic cardiovascular disease that often goes undetected in young athletes. Neither history nor physical examination are reliable to identify those at risk. The objective of this study is to determine whether minimally trained medical student volunteers can use ultrasound to screen for HCM. METHODS: This was a prospective enrollment of young athletes performed at 12 area high schools and three area colleges, between May 2012 and August 2013. All participants underwent point-of-care ultrasound performed screening for HCM by trained medical students and reviewed by a pediatric cardiologist. An interventricular septum to left ventricular posterior wall ratio greater than 1.25 was considered to be abnormal (positive screen). RESULTS: A total of 2332 participants were enrolled. There were 137 (5.8%) with a positive screening for HCM, of which 7 (5.1%) were confirmed to have HCM by a pediatric cardiologist. In a small cohort with positive screen for HCM, there was a 100% sensitivity (95% confidence interval, 59.04 to 100%) and 4.86% (95% confidence interval, 1.98 to 9.76%) positive predictive value of for having HCM. CONCLUSIONS: Volunteer medical students, using point-of-care ultrasound, were able to effectively screen for HCM in young athletes.

Integration of Ultrasound in Medical Education at United States Medical Schools: A National Survey of Directors' Experiences.

OBJECTIVES: Despite the rise of ultrasound in medical education (USMED), multiple barriers impede the implementation of such curricula in medical schools. No studies to date have surveyed individuals who are successfully championing USMED programs. This study aimed to investigate the experiences with ultrasound integration as perceived by active USMED directors across the United States. METHODS: In 2014, all allopathic and osteopathic medical schools in the United States were contacted regarding their status with ultrasound education. For schools with required point-of-care ultrasound curricula, we identified the USMED directors in charge of the ultrasound programs and sent them a 27-question survey. The survey included background information about the directors, ultrasound program details, the barriers directors faced toward implementation, and the directors' attitudes toward ultrasound education. RESULTS: One-hundred seventy-three medical schools were contacted, and 48 (27.7%) reported having a formal USMED curriculum. Thirty-six USMED directors responded to the survey. The average number of years of USMED curriculum integration was 2.8 years (SD, 2.9). Mandatory ultrasound curricula had most commonly been implemented into years 1 and 2 of medical school (71.4% and 62.9%, respectively). The most common barriers faced by these directors when implementing their ultrasound programs were the lack of funding for faculty/ equipment (52.9%) and lack of time in current medical curricula (50.0%). CONCLUSIONS: Financial commitments and the full schedules of medical schools are the current prevailing roadblocks to implementation of ultrasound education. Experiences drawn from current USMED directors in this study may be used to help programs starting their own curricula.

Integration of Ultrasound in Undergraduate Medical Education at the California Medical Schools: A Discussion of Common Challenges and Strategies From the UMeCali Experience.

Since the first medical student ultrasound electives became available more than a decade ago, ultrasound in undergraduate medical education has gained increasing popularity. More than a dozen medical schools have fully integrated ultrasound education in their curricula, with several dozen more institutions planning to follow suit. Starting in June 2012, a working group of emergency ultrasound faculty at the California medical schools began to meet to discuss barriers as well as innovative approaches to implementing ultrasound education in undergraduate medical education. It became clear that an ongoing collaborative could be formed to discuss barriers, exchange ideas, and lend support for this initiative. The group, termed Ultrasound in Medical Education, California (UMeCali), was formed with 2 main goals: to exchange ideas and resources in facilitating ultrasound education and to develop a white paper to discuss our experiences. Five common themes integral to successful ultrasound education in undergraduate medical education are discussed in this article: (1) initiating an ultrasound education program; (2) the role of medical student involvement; (3) integration of ultrasound in the preclinical years; (4) developing longitudinal ultrasound education; and (5) addressing competency.

Thrombosis of Inferior Vena Cava Diagnosed Using Point-of-Care Ultrasound After Pediatric Near-Syncope.

BACKGROUND: Venous thromboembolism (VTE) is extremely rare but under recognized in the pediatric population. Although the literature on the use of ultrasound to detect VTEs in adults is plentiful, little has been documented on its use in the pediatric population. CASE REPORT: We present a case of a healthy 16-year-old female who presented to our emergency department with 3 months of dyspnea on exertion and one episode of near-syncope. Point-of-care cardiac ultrasound identified an inferior vena cava thrombosis. Subsequent computed tomography angiography diagnosed concurrent bilateral pulmonary emboli (PE). The patient's identical twin sister presented with similar symptoms shortly thereafter and was also diagnosed with VTE and bilateral PE. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case demonstrates an instance of VTE and pulmonary embolism in twin adolescent girls. Physical examination findings, electrocardiogram, chest x-ray study, and several previous evaluations did not reveal the diagnosis. Point of care ultrasound was used to correctly diagnosis VTE and for heightened concern for a pulmonary embolism.

Implementation and assessment of a curriculum for bedside ultrasound training.

OBJECTIVES: This study assessed a curriculum for bedside ultrasound (US) and compared outcomes from 2 common training pathways. METHODS: The program consisted of e-learning paired with expert-led hands-on training administered to pulmonary/critical care and cardiology fellows with no prior formal training in bedside US. This "simulation-based learner" group completed a survey of attitudes and confidence before and after training, and knowledge and skills were assessed after training. The surveys and scores of the simulation-based learners were compared to the scores of "experts," who were US-trained emergency physicians, and "apprentice learners," who were intensivist physicians informally trained in bedside US on the job during fellowships. RESULTS: There was a significant difference in the self-reported level of prior training between the groups (simulation-based learners, 2.8; apprentice learners, 3.7; experts, 4.1, on a scale of 1-5 [P= .02]) but no difference in the interest level or perceived importance of bedside US. The study curriculum was successful, as shown by scores that exceeded the comparison groups in the cardiac and pulmonary courses (cardiac: simulation-based learners, 80%; apprentice learners, 73%; experts, 62% [P= .001]; pulmonary: 84%, 75%, and 72%, respectively [P =.02]). The simulation-based learners gained confidence in skills, whereas the comparison groups lost confidence after testing (P < .005); however, the simulation-based learners gained confidence in US subject areas that were not taught (abdomen [P <.002] and miscellaneous [P =.005]). CONCLUSIONS: The simulation-based learner curriculum resulted in comparable or greater knowledge and confidence in each area of US versus the comparison groups. Findings of overgeneralization of confidence highlight the importance of quality assurance and supervision in bedside US training programs.

The Absence of Gallstones on Point-of-Care Ultrasound Rules Out Acute Cholecystitis.

BACKGROUND: Cholelithiasis affects an estimated 20 million people in the United States yearly; 20% of symptomatic patients will develop acute cholecystitis (AC). A recent single-center study estimating test characteristics of point-of-care ultrasonography (POCUS) for the detection of AC, as defined by gallstones plus sonographic Murphy's or pericholecystic fluid or gallbladder wall-thickening, resulted in a sensitivity and specificity of 87% (95% confidence interval [CI] 66-97) and 82% (95% CI 74-88), respectively. No prior studies have been conducted to estimate the test characteristics of POCUS for the purpose of excluding acute calculous cholecystitis. OBJECTIVE: To determine whether the finding of gallstones alone on POCUS has high sensitivity, high negative predictive value, and low negative likelihood ratio for the exclusion of AC. METHODS: We conducted an analysis using data from a prospective cross-sectional single-center study of POCUS test to estimate the test characteristics using a simplified definition of a positive test - the presence of gallstones alone. Clinical follow-up and pathology reports were used as the reference standard. Test characteristics were calculated and compared to the standard definition, gallstones plus one secondary finding. RESULTS: The overall prevalence of AC was 14% (23 pathology-confirmed cases of 164 included patients). The sensitivity of the simplified definition was 100% (95% CI 85.7-100), negative predictive value 100% (95% CI 92.2-100), and negative likelihood ratio was < 0.1, compared to a sensitivity of 87% (95% CI 66-97%), negative predictive value 97% (95% CI 93-99%), and negative likelihood ratio of 0.16 (95% CI 0.06-0.5). CONCLUSION: Simplifying the definition of the test findings on POCUS to gallstones alone has excellent sensitivity and negative predictive value for the exclusion of AC. This finding, if broadly validated prospectively, confirms the practice of excluding acute calculous cholecystitis using POCUS in emergency department patients.

Remote, Synchronous, Hands-On Ultrasound Education.

BACKGROUND: Ultrasound has become a major diagnostic tool in many parts of the world, with broad clinical applications. Ultrasound provides a noninvasive, painless mode of diagnostics that produces instant results. Disseminating ultrasound skills to remote and rural communities has become a challenge for many medical schools, particularly those where distances are great and the density of population is low. MATERIALS AND METHODS: The University of California, Irvine School of Medicine and the University of New England School of Rural Medicine in Australia piloted the use of dual video feeds in two scenarios: (1) to display the instructor's ultrasound feed and the instructor's transducer placement to provide guidance for remote students; and (2) to display side-by-side views of the instructor's and the remote student's ultrasound feeds to allow the instructor to guide the remote student in his or her transducer placement. RESULTS AND CONCLUSIONS: Using high-speed broadband connections, the two schools demonstrated the feasibility of remote, synchronous, practical, and hands-on ultrasound training and instruction over international distances. This opens up a broad range of possibilities for future remote ultrasound education.

Emergency biliary sonography: utility of common bile duct measurement in the diagnosis of cholecystitis and choledocholithiasis.

BACKGROUND: Measurement of the common bile duct (CBD) has traditionally been considered an integral part of gallbladder sonography, but accurate identification of the CBD can be difficult for novice sonographers. OBJECTIVE: To determine the prevalence of isolated sonographic CBD dilation in emergency department (ED) patients with cholecystitis or choledocholithiasis without laboratory abnormalities or other pathologic findings on biliary ultrasound. METHODS: We conducted a retrospective chart review on two separate ED patient cohorts between June 2000 and June 2010. The first cohort comprised all ED patients undergoing a biliary ultrasound and subsequent cholecystectomy for presumed cholecystitis. The second cohort consisted of all ED patients receiving a biliary ultrasound who were ultimately diagnosed with choledocholithiasis. Ultrasound data and contemporaneous laboratory values were collected. Postoperative gallbladder pathology reports and endoscopic retrograde cholangiopancreatography (ERCP) reports were used as the criterion standard for final diagnosis. RESULTS: Of 666 cases of cholecystitis, there were 251 (37.7%) with a dilated CBD > 6 mm and only 2 cases (0.3%; 95% confidence interval [CI] 0.0-0.7%) of isolated CBD dilation with an otherwise negative ultrasound and normal laboratory values. Of 111 cases of choledocholithiasis, there were 80 (72.0%) with a dilated CBD and only 1 case (0.9%; 95% CI 0.0-2.7%) with an otherwise negative ultrasound and normal laboratory values. CONCLUSION: The prevalence of isolated sonographic CBD dilation in cholecystitis and choledocholithiasis is <1%. Omission of CBD measurement is unlikely to result in missed cholecystitis or choledocholithiasis in the setting of a routine ED evaluation with an otherwise normal ultrasound and normal laboratory values.

A pilot study examining the viability of a Prehospital Assessment with UltraSound for Emergencies (PAUSE) protocol.

BACKGROUND: Prehospital ultrasound has been shown to aid in the diagnosis of multiple conditions that do not generally change prehospital management. On the other hand, the diagnoses of cardiac tamponade, tension pneumothorax, or cardiac standstill may directly impact patient resuscitation in the field. STUDY OBJECTIVE: To determine if prehospital care providers can learn to acquire and recognize ultrasound images for several life-threatening conditions using the Prehospital Assessment with UltraSound for Emergencies (PAUSE) protocol. METHODS: This is a prospective, educational intervention pilot study at an urban fire department with integrated emergency medical services (EMS). We enrolled 20 emergency medical technicians--paramedic with no prior ultrasonography training. Subjects underwent a 2-h training session on basic ultrasonography of the lungs and heart to evaluate for pneumothorax, pericardial effusion, and cardiac activity. Subjects were tested on image interpretation as well as image acquisition skills. Two bedside ultrasound-trained emergency physicians scored images for adequacy. Image interpretation testing was performed using pre-obtained ultrasound clips containing normal and abnormal images. RESULTS: All subjects appropriately identified the pleural line, and 19 of 20 paramedics achieved a Cardiac Ultrasound Structural Assessment Scale score of ≥4. For the image interpretation phase, the mean PAUSE protocol video test score was 9.1 out of a possible 10 (95% confidence interval 8.6-9.6). CONCLUSION: Paramedics were able to perform the PAUSE protocol and recognize the presence of pneumothorax, pericardial effusion, and cardiac standstill. The PAUSE protocol may potentially be useful in rapidly detecting specific life-threatening pathology in the prehospital environment, and warrants further study in existing EMS systems.

A prospective evaluation of emergency department bedside ultrasonography for the detection of acute cholecystitis.

STUDY OBJECTIVE: We assess the diagnostic accuracy of emergency physician-performed bedside ultrasonography and radiology ultrasonography for the detection of cholecystitis, as determined by surgical pathology. METHODS: We conducted a prospective, observational study on a convenience sample of emergency department (ED) patients presenting with suspected cholecystitis from May 2006 to February 2008. Bedside gallbladder ultrasonography was performed by emergency medicine residents and attending physicians at an academic institution. Emergency physicians assessed for gallstones, a sonographic Murphy's sign, gallbladder wall thickness, and pericholecystic fluid, and the findings were recorded before formal imaging. The test characteristics of bedside and radiology ultrasonography were determined by comparing their respective results to pathology reports and clinical follow-up at 2 weeks. RESULTS: Of the 193 patients enrolled, 189 were evaluated by bedside ultrasonography. Forty-three emergency physicians conducted the ultrasonography, and each physician performed a median of 2 tests. After the bedside ultrasonography, 125 patients received additional radiology ultrasonography. Twenty-six patients underwent cholecystectomy, 23 had pathology-confirmed cholecystitis, and 163 were discharged home to follow-up. Twenty-five were excluded (23 lost to follow-up and 2 unavailable pathology). The test characteristics of bedside ultrasonography were sensitivity 87% (95% confidence interval [CI] 66% to 97%), specificity 82% (95% CI 74% to 88%), positive likelihood ratio 4.7 (95% CI 3.2 to 6.9), negative likelihood ratio 0.16 (95% CI 0.06 to 0.46), positive predictive value 44% (95% CI 29% to 59%), and negative predictive value 97% (95% CI 93% to 99%). The test characteristics of radiology ultrasonography were sensitivity 83% (95% CI 61% to 95%), specificity 86% (95% CI 77% to 92%), positive likelihood ratio 5.7 (95% CI 3.3 to 9.8), negative likelihood ratio 0.20 (95% CI 0.08 to 0.50), positive predictive value 59% (95% CI 41% to 76%), and negative predictive value 95% (95% CI 88% to 99%). CONCLUSION: The test characteristics of emergency physician-performed bedside ultrasonography for the detection of acute cholecystitis are similar to the test characteristics of radiology ultrasonography. Patients with a negative ED bedside ultrasonography result are unlikely to require cholecystectomy or admission for cholecystitis within 2 weeks of their initial presentation.

Emergency and critical care imaging.

Care for patients who have time-sensitive disease processes in the emergency department and critical care settings is optimized with rapid diagnosis and intervention. Recent advances in medical imaging have increased portability, decreased image acquisition time, improved data resolution, and increased use of noninvasive studies. This article discusses the use of portable imaging techniques such as bedside ultrasound and radiography as well as CT and CT angiography in the diagnosis and care of critically ill patients.

Prospective evaluation of emergency physician performed bedside ultrasound to detect acute appendicitis.

OBJECTIVES: To evaluate the accuracy of emergency physicians using bedside ultrasound to detect appendicitis (BUSA). METHODS: Patients presenting to the emergency department with a clinical suspicion of appendicitis were prospectively enrolled and received a 5-min BUSA. Patients received routine work-up for acute appendicitis as deemed appropriate by the attending physician. Radiologists and consulting surgeons were blinded to BUSA results. The criterion standard for the presence or absence of acute appendicitis was the pathology report for patients who received appendectomies, and telephone follow-up for patients discharged home without surgical intervention. RESULTS: A total of 132 patients were enrolled. In 44 cases BUSA was positive. Of these, 37 had surgical pathology reports consistent with acute appendicitis, whereas seven did not have appendicitis. In 82 cases, BUSA was negative. Of these, 62 were determined not to have appendicitis, whereas 20 had appendicitis by pathology. Sensitivity for BUSA was 65% [95% confidence interval (CI) 52-76], specificity was 90% (95% CI 81-95), positive predictive value was 84% (95% CI 71-92), and negative predictive value was 76% (95% CI 65-84). The likelihood ratio of a positive BUSA was 6.4 (95% CI 3.1-13.2). Five patients discharged home with a diagnosis other than appendicitis were unable to be reached by telephone, and were excluded from data analysis. CONCLUSION: Our study gives insufficient evidence to support the use of bedside ultrasound by emergency physicians to rule out appendicitis. The high specificity in our study, however, suggests that with further training, BUSA may be useful to rule-in appendicitis in some patients.

Vaginal bleeding before 20 weeks gestation due to placental abruption leading to disseminated intravascular coagulation and fetal loss after appearing to satisfy criteria for routine threatened abortion: a case report and brief review of the literature.

We present a case of placental abruption with concomitant disseminated intravascular coagulation in a woman who presented with vaginal bleeding. A 32-year-old pregnant woman at 17 and 4/7 weeks gestation with a 1-month history of intermittent abdominal pain presented to our Emergency Department (ED) with 1 h of vaginal bleeding. Upon initial history, the patient reported that she was diagnosed with "blood behind the placenta" the day before and was discharged on pelvic precautions. An ED ultrasound confirmed the sub-amniotic hematoma with placental hematoma and a viable intrauterine fetus. A low fibrinogen level was suggested for disseminated intravascular coagulation and increasing hemorrhage necessitated dilation and evacuation and multiple units of blood products on an emergent basis. Only a few cases have been described in the literature demonstrating disseminated intravascular coagulation in patients at fewer than 20 weeks gestation with routine ultrasound findings of live intrauterine pregnancy and subchorionic hemorrhage.

Comparison of ultrasound-measured properties of the common carotid artery to tobacco smoke exposure in a cohort of Indonesian patients.

BACKGROUND: The purpose of this study was to use point-of-care ultrasound (POCUS) to investigate the relationship between tobacco smoke exposure and the characteristics of the common carotid artery (CCA). The effect of both primary and secondary smoking on CCA properties was evaluated. METHODS: We performed a prospective cross-sectional study across 20 primary care clinics in Bandung, West Java, Indonesia in July 2016. Point of care ultrasound was performed on a convenience sample of Indonesian patients presenting to clinic. The CCA wall stiffness and carotid intima-media thickness (CIMT) were measured during diastole and systole. These measurements were correlated with smoke exposure and cardiovascular disease. RESULTS: We enrolled 663 patients in the study, with 426 patients enrolled in the smoking category and 237 patients enrolled in the second-hand smoke category. There was an overall positive correlation with the measured lifestyle factors and the ultrasound-measured variables in the group of individuals who smoked. For all variables, age seemed to contribute the most out of all of the lifestyle factors for the positive changes in CIMT and CCA wall stiffness. CONCLUSION: Our data yielded correlations between CCA properties and cardiovascular risk, as well as between CIMT and arterial stiffness. We were also able to demonstrate an increase in thickness of the CIMT in patients who have been exposed by tobacco through the use of ultrasound. Further large scale studies comparing patients with multiple cardiac risk factors need to be performed to confirm the utility of ultrasound findings of cardiovascular disease and stroke.

Ultrasound-Guided Cannulation: Time to Bring Subclavian Central Lines Back.

Despite multiple advantages, subclavian vein (SCV) cannulation via the traditional landmark approach has become less used in comparison to ultrasound (US) guided internal jugular catheterization due to a higher rate of mechanical complications. A growing body of evidence indicates that SCV catheterization with real-time US guidance can be accomplished safely and efficiently. While several cannulation approaches with real-time US guidance have been described, available literature suggests that the infraclavicular, longitudinal "in-plane" technique may be preferred. This approach allows for direct visualization of needle advancement, which reduces risk of complications and improves successful placement. Infraclavicular SCV cannulation requires simultaneous use of US during needle advancement, but for an inexperienced operator, it is more easily learned compared to the traditional landmark approach. In this article, we review the evidence supporting the use of US guidance for SCV catheterization and discuss technical aspects of the procedure itself.