Optimal bowel diameter thresholds for diagnosing small bowel obstruction and surgical intervention with point-of-care ultrasound.

OBJECTIVES: A bowel diameter threshold of ≥2.5 cm, originally derived from the research using computed tomography, is frequently used for diagnosing small bowel obstruction (SBO) with point-of-care ultrasound (POCUS). We sought to determine the optimal bowel diameter threshold for diagnosing SBO using POCUS and its accuracy in predicting surgical intervention. METHODS: We conducted a secondary analysis using individual patient-level data from a previous systematic review on POCUS for SBO diagnosis across five academic EDs. Patient data were collected, including imaging results, surgical findings, and final diagnosis. The measured diameter of the small bowel using POCUS was recorded. ROC area under the receiver operating characteristic curves (AUC) were constructed to determine the optimal threshold for bowel diameter in predicting SBO diagnosis and surgical intervention. Subgroup analyses were performed based on sex and age. RESULTS: A total of 403 patients had individual patient-level data available, with 367 patients included in the final analysis. The most accurate bowel diameter overall for predicting SBO was 2.75 cm (AUC = 0.76, 95% CI 0.71-0.81). A bowel diameter of ≤1.7 cm had 100% sensitivity with no miss rate, while a bowel diameter of ≥4 cm had 90.7% specificity in confirming SBO. Patients under 65 had an optimal threshold of 2.75 cm versus 2.95 cm in patients over 65. Females had an optimal threshold of 2.75 cm, while males had a value of 2.95 cm. There was no significant correlation between bowel diameter thresholds and surgical intervention. CONCLUSION: A bowel diameter threshold of 2.75 cm on POCUS is more discriminative diagnostic accuracy for diagnosing SBO. Patients' age and sex may impact diagnostic accuracy, suggesting that tailored approaches may be needed.

Multi-center analysis of point-of-care ultrasound for small bowel obstruction: A systematic review and individual patient-level meta-analysis.

OBJECTIVE: The study aimed to assess the diagnostic accuracy of point-of-care ultrasound (POCUS) in identifying small bowel obstruction (SBO) and to investigate the impact of clinician experience level and body mass index (BMI) on POCUS performance for diagnosing SBO in the Emergency Department. METHODS: We systematically searched PubMed and Cochrane databases from January 2011-2022. We performed a meta-analysis using individual patient-level data from prospective diagnostic accuracy studies from which we obtained data from the corresponding authors. Overall test characteristics and subgroup analysis across clinician experience levels and a range of BMI were calculated. The primary outcome was SBO as the final diagnosis during hospitalization. RESULTS: We included Individual patient data from 433 patients from 5 prospective studies. Overall, 33% of patients had a final diagnosis of SBO. POCUS had 83.0% (95%CI 71.7%-90.4%) sensitivity and 93.0% (95%CI 55.3%-99.3%) specificity; LR+ was 11.9 (95%CI 1.2-114.9) and LR- was 0.2 (95%CI 0.1-0.3). Residents had exhibited a sensitivity of 73.0% (95%CI 56.6%-84.9%) and specificity of 88.2% (95%CI 58.8%-97.5%), whereas attendings had demonstrated a sensitivity of 87.7% (95%CI 71.1%-95.4%) and specificity of 91.4% (95%CI 57.4%-98.8%). Among those patients with BMI<30 kg/m2, POCUS showed a sensitivity of 88.6% (95%CI 79.5%-94.7%) and a specificity of 84.0% (95%CI 75.3%-90.6%), while patients with BMI ≥ 30 kg/m2 exhibited a sensitivity of 72.0% (95%CI 50.6%-87.9%) and specificity of 89.5% (95%CI 75.2%-97.1%). CONCLUSIONS: POCUS correctly identified those patients with SBO with high sensitivity and specificity. Diagnostic accuracy was slightly reduced when performed by resident physicians and among patients with a BMI ≥ 30 kg/m2. REGISTRATION: PROSPERO registration number: CRD42022303598.

Point of Care Ultrasound in the Diagnosis of Necrotizing Fasciitis.

BACKGROUND: Necrotizing fasciitis (NF) is a severe, life-threatening soft tissue infection requiring prompt diagnosis and immediate surgical debridement. Imaging, including a computed tomography (CT) scan, can often aid in the diagnosis, though it can prolong time to treatment and diagnosis. Point-of-care ultrasound (POCUS) is often used in the ED to identify soft tissue infections. The objective of this study is to evaluate the use of POCUS to identify NF in patients presenting to the emergency department. METHODS: We prospectively enrolled patients who presented to the emergency department (ED) with suspected soft tissue infection who received a computed tomography and/or surgical consult. POCUS images of the suspected site of infection were obtained by the emergency medicine physician and interpreted based on sonographic findings of NF. These findings were compared with CT scan or surgical impression. RESULTS: We enrolled 64 patients in this study. Eight were determined to be at high risk of having NF based on CT scan and/or surgical impression. All of these patients also had POCUS images interpreted as concerning for NF. Furthermore, 56 patients were classified as being low risk for having NF based on CT scan and/or surgical impression. All but one of these patients had POCUS images interpreted as not concerning for NF. CONCLUSIONS: Our data indicates that POCUS can be used to identify NF with a high sensitivity and specificity.

Evaluation of Adherence to Emergency Department Point-of-Care Ultrasound Documentation and Billing Following Intervention.

Background: Over the past few years, both the scope and utility of point-of-care ultrasound (POCUS) have tremendously expanded in the clinical setting. Despite this growth, few studies have evaluated the compliance, documentation, and billing of POCUS in the emergency department (ED). The objective of this study was to evaluate the compliance of billing and documentation of POCUS and determine if a single, individualized e-mail feedback can help improve billing and documentation. Methods: We performed a 6-week prospective review of ED POCUSs performed. Following this review, all emergency physicians were sent an individualized e-mail regarding their ultrasound performance including the total number of ultrasounds, ultrasounds per shift, and breakdown of specific ultrasound types. Following this intervention, we collected data from an additional 6 weeks regarding ultrasound billing performance. Results: A total of 1532 POCUS scans were recorded for data collection. Eight hundred and five scans were enrolled in the preintervention group and 727 scans in the postintervention group. Twelve different types of POCUS scans were recorded. The preintervention group had documented 484/805 scans resulting in a 60.1% (confidence interval [CI] 56.7%-63.5%) documentation ratio. The postintervention group had documented 521/727 resulting in a 71.7% (CI 68.2%-74.9%) documentation ratio. Conclusion: The implementation of timely quality assurance with continuous billing reminders is essential for the maintenance and fiscal sustainability of an emergency medicine ultrasound program. Future studies should further elucidate and quantify the financial impact of modifiable factors within EDs' ultrasound documentation and billing practices.

The association of smoking with ultrasound-measured kidney dimensions
.

PURPOSE: Ultrasound is considered a preferred first-line imaging technique for the assessment of kidney function. The potential relationship between tobacco smoke exposure and ultrasound-measured renal characteristics has yet to be explored. We hypothesized that exposure to tobacco smoke would be associated with reduced kidney dimensions. MATERIALS AND METHODS: This was a cross-sectional study that included all individuals over age 18 at a single site in Mojokerto, Indonesia. A questionnaire was used to assess prior history and environmental exposure, and blinded evaluators performed ultrasound assessments. Six kidney parameters (length, width, and parenchymal thickness of each kidney) were considered as dependent variables, and statistical relationships were assessed using multivariate analysis. Echogenicity was evaluated using a 5-point grading scale described previously. RESULTS: Of the 445 participants assessed, a total of 138 male and 269 female subjects were included in the final analysis. There was a statistically significant association between kidney measures and the following independent variables: pack years smoking (p < 0.001), height (p < 0.001), weight (p < 0.001), and beginning to smoke at the age of 25 or younger (p < 0.001). There was not a statistically significant association between kidney measures and hypertension (p > 0.05) or diabetes (p > 0.05). Echogenicity was similar among all smoking groups. CONCLUSION: Kidney dimensions were decreased in individuals with increased smoking history. This association is notable, particularly given that statistically significant associations were not observed between renal dimensions and hypertension or diabetes. The null findings using echogenicity are consistent with previous studies.

Evaluation of a point-of-care ultrasound curriculum taught by medical students for physicians, nurses, and midwives in rural Indonesia.

PURPOSE: In the Indonesian health-care system, nurses and midwives often serve as the primary health-care providers due to physician shortages. Seeking to address the need for medical care in resource-limited environments, some have advocated for portable equipment in the hands of health-care providers. We hypothesized that medical students are able to effectively teach point-of-care ultrasound (POCUS) to physicians, nurses, and midwives in rural Indonesia. METHODS: We conducted a prospective, observational study using health-care practitioners from a clinic and accredited school for nursing and midwifery in Mojokerto, East Java, Indonesia. Enrolled practitioners took part in a 4-week POCUS course followed by postinstructional testing. RESULTS: A total of 55 health-care practitioners completed the course. This included 19 physicians, 13 nurses, and 19 midwives. Of the 55 clinicians, 43 (72%) passed the course and 12 (28%) failed. CONCLUSIONS: Physicians, nurses, and midwives in rural Indonesia showed significant acquisition of ultrasound (US) knowledge and skills following a 4-week US course. Following training, all three groups displayed skills in practical US use during a postcourse practical examination. This is one of the first studies to assess the efficacy of medical students teaching POCUS to midwives and nurses.

Tricuspid annular plane of systolic excursion to prognosticate acute pulmonary symptomatic embolism (TAPSEPAPSE study).

INTRODUCTION: The imaging standard for evaluation of acute pulmonary embolism (PE) includes a computed tomography pulmonary angiogram. Ultrasonography has shown promise in obtaining the tricuspid annular plane systolic excursion (TAPSE) measurements, which may be of clinical importance in patients with acute PE. The objective of this study is to evaluate the diagnostic capability of TAPSE measurements for patients with suspicion for acute PE. METHODS: We prospectively enrolled patients who came to the emergency department with suspicion of acute PE. Each patient underwent a point-of-care sonogram where a TAPSE measurement was obtained, followed by computed tomography pulmonary angiogram. Based on the computed tomography pulmonary angiogram findings, patients were grouped into 3 categories: no acute PE, clinically insignificant acute PE, or clinically significant acute PE. RESULTS: We enrolled 87 patients in this study. Twenty-three (26.4%) of these patients were diagnosed with PE. Of patients with PE, 15 (65%) were found to have a clinically significant acute PE. Analysis of mean TAPSE measurements between patients with clinically significant acute PE and those with insignificant or no PE was 15.2 mm and 22.7 mm, respectively (P ≤ .0001). Following receiver operating characteristic curve analysis, optimum TAPSE measurement to identify clinically significant acute PE is 18.2 mm. A cutoff TAPSE measurement of 15.2 mm shows a sensitivity of 53.3% (95% confidence interval, 26.7%-80%) and a specificity of 100% (95% confidence interval, 100%-100%) for the diagnosis of a clinically significant PE. CONCLUSIONS: Our data suggest that TAPSE measurements less than 15.2 mm have a high specificity for identifying clinically significant acute PE.

A Prospective Evaluation of Point of Care Ultrasound Teaching in Switzerland.

CONTEXT: As the utility of point-of-care ultrasound (POCUS) continues to expand in the medical field, there is a need for effective educational methods. In Switzerland, medical education follows the European model and lasts 6 years, focusing on preclinical training during the first 2 years. No previous studies have evaluated the optimal time for teaching ultrasound in European medical education. AIMS: The aim of this study is to provide ultrasound training to medical students in Switzerland at varying times during their clinical training to determine if the level of training plays a role in their ability to comprehend and to apply basic POCUS skills. METHODS: We performed an observational study utilizing a convenience sample of Swiss medical students between July 11, 2016 and August 6, 2016. They were taught a 2-day POCUS course by five American-trained 1st-year medical students. Following this course, students were evaluated with written and clinical examination. RESULTS: 100 Swiss medical students were enrolled in the study. A total of 59 of these students were early clinical students, and 41 students were late clinical students. A two-tailed t-test was performed and demonstrated that the late clinical students performed better than the early clinical students on the written assessment; however, no difference was found in clinical skill. CONCLUSION: Our data suggest that Swiss medical students can learn and perform POCUS after a 2-day instructional taught by trained 1st-year American medical students. No difference was found between students in early clinical training and late clinical training for the ability to perform POCUS.

Utility of common bile duct measurement in ED point of care ultrasound: A prospective study.

BACKGROUND: Measurement of the common bile duct (CBD) is considered a fundamental component of biliary point-of-care ultrasound (POCUS), but can be technically challenging. OBJECTIVE: The primary objective of this study was to determine whether CBD diameter contributes to the diagnosis of complicated biliary pathology in emergency department (ED) patients with normal laboratory values and no abnormal biliary POCUS findings aside from cholelithiasis. METHODS: We performed a prospective, observational study of adult ED patients undergoing POCUS of the right upper quadrant (RUQ) and serum laboratory studies for suspected biliary pathology. The primary outcome was complicated biliary pathology occurring in the setting of normal laboratory values and a POCUS demonstrating the absence of gallbladder wall thickening (GWT), pericholecystic fluid (PCF) and sonographic Murphy's sign (SMS). The association between CBD dilation and complicated biliary pathology was assessed using logistic regression to control for other factors, including laboratory findings, cholelithiasis and other sonographic abnormalities. RESULTS: A total of 158 patients were included in the study. 76 (48.1%) received non-biliary diagnoses and 82 (51.9%) were diagnosed with biliary pathology. Complicated biliary pathology was diagnosed in 39 patients. Sensitivity of CBD dilation for complicated biliary pathology was 23.7% and specificity was 77.9%. CONCLUSION: Of patients diagnosed with biliary pathology, none had isolated CBD dilatation. In the absence of abnormal laboratory values and GWT, PCF or SMS on POCUS, obtaining a CBD measurement is unlikely to contribute to the evaluation of this patient population.

A Prospective Evaluation of Transverse Tracheal Sonography During Emergent Intubation by Emergency Medicine Resident Physicians.

OBJECTIVES: Establishing a definitive airway is often the first step in emergency department treatment of critically ill patients. Currently, there is no agreed upon consensus as to the most efficacious method of airway confirmation. Our objective was to determine the diagnostic accuracy of real-time sonography performed by resident physicians to confirm placement of the endotracheal tube during emergent intubation. METHODS: We performed a prospective cohort study of adult patients in the emergency department undergoing emergent endotracheal intubation. Thirty emergency medicine residents, who were blinded to end-tidal carbon dioxide detection results, performed real-time transverse tracheal sonography during intubation to evaluate correct endotracheal tube placement. RESULTS: Seventy-two patients were enrolled in the study. Sixty-eight instances (94.4%) were interpreted as correct placement in the trachea; 4 (5.6%) were interpreted as esophageal, of which 1 was a false-negative finding, therefore conferring sensitivity of 98.5% (95% confidence interval, 92.1%-99.9%) and specificity of 75.0% (95% confidence interval, 19.4%-99.4%) for correct placement. There was no significant difference in accuracy among resident sonographers with different levels of residency training. CONCLUSIONS: A simple transverse tracheal sonographic examination performed by emergency medicine resident physicians can be used as an adjunct to help confirm correct endotracheal tube placement during intubation. In our cohort, the level of training did not appear to affect the ability of residents to correctly identify the endotracheal tube position.

Implementation of a 4-Year Point-of-Care Ultrasound Curriculum in a Liaison Committee on Medical Education-Accredited US Medical School.

OBJECTIVES: The established benefits of point-of-care ultrasound have given rise to multiple new and innovative curriculums to incorporate ultrasound teaching into medical education. This study sought to measure the educational success of a comprehensive and integrated 4-year point-of-care ultrasound curriculum. METHODS: We integrated a curriculum consisting of traditional didactics combined with asynchronous learning modules and hands-on practice on live models with skilled sonographers into all 4 years of education at a Liaison Committee on Medical Education-accredited US Medical School. Each graduating student was administered an exit examination with 48 questions that corresponded to ultrasound milestones. RESULTS: Ninety-five percent (n = 84) of fourth-year medical students completed the exit examination. The mean score was 79.5% (SD, 10.2%), with mean scores on the ultrasound physics and anatomy subsections being 77.1% (SD, 11.0%) and 85.9% (SD, 21.0%), respectively. CONCLUSIONS: A comprehensive 4-year point-of-care ultrasound curriculum integrated into medical school may successfully equip graduating medical students with a fundamental understanding of ultrasound physics, anatomy, and disease recognition.

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.

Pediatric Acute Ischemic Cerebral Vascular Accidents: A Case Report.

An 8-year-old girl presented to the pediatric emergency department (ED) with left-sided weakness. Workup consisted of labs and imaging including magnetic resonance imaging showing an acute ischemic stroke. Literature regarding pediatric acute ischemic stroke is minimal, and there are few protocols guiding care in the pediatric population. Current recommendations include treatment with unfractionated heparin or low-molecular-weight heparin (LMWH) with subsequent daily aspirin prophylaxis. Further large scale studies are needed to produce protocols and generalizable treatment plans.

Ultrasound-guided central venous access: which probe is preferred for viewing the subclavian vein using a supraclavicular approach?

BACKGROUND: Point-of-care ultrasound guidance using a linear probe is well established as a tool to increase safety when performing a supradiaphragmatic cannulation of the internal jugular central vein. However, little data exist on which probe is best for performing a supradiaphragmatic cannulation of the subclavian vein. METHODS: This was a prospective, observational study at a single-site emergency department, where 5 different physician sonologists evaluate individual practice preference for visualization of the subclavian vein using a supraclavicular approach with 2 different linear probes and 1 endocavitary probe. RESULTS: Of 155 patients enrolled, there was no clear preference any of the probes (P= .03). After pooling linear probe preference, there was a preference for either linear probe over the alternative endocavitary probe (76.8% vs 23.1%, P< .05). CONCLUSION: We observed a preference for a linear probe over an endocavitary probe. Further investigation is necessary to determine which probe is optimal for this application.

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.

Using a Linear Probe Ultrasound for the Detection of First-Trimester Pregnancies in the Emergency Department.

Linear probe point-of-care ultrasound (LPUS) presents a less invasive alternative for identifying intrauterine pregnancies (IUPs) compared to usual practice (transabdominal (TAUS) or transvaginal (TVUS) ultrasound). TAUS and TVUS can be invasive or produce lower-resolution images than LPUS. The purpose of this study is to determine whether a linear probe alone can identify first-trimester IUPs. A convenience sample of 21 patients were enrolled at the University of California Irvine ED during a 7-month period. The inclusion criteria were English- or Spanish-speaking women (≥18 years) in their first trimester of pregnancy (≤12 weeks pregnant) with a body mass index (BMI) of <35. The exclusion criteria were psychiatric, incarcerated, or cognitively impaired patients. An ED physician performed LPUS and ordered a confirmatory ultrasound. The 21 patients enrolled had a mean age of 28.6 ± 6.60 years, BMI of 26.6 ± 5.03, and gestational age of 7.4 ± 2.69 weeks. Considering the 95% confidence interval, we are 97.5% confident that the sensitivity and specificity of LPUS to identify IUPs does not exceed 67.1% and 93.2%, respectively. Our pilot data did not demonstrate that LPUS can independently visualize IUPs in first-trimester patients.

Application of Point-of-care Ultrasound for Screening Climbers at High Altitude for Pulmonary B-lines.

INTRODUCTION: High-altitude pulmonary edema (HAPE) occurs as a result of rapid ascent to altitude faster than the acclimatization processes of the body. Symptoms can begin at an elevation of 2,500 meters above sea level. Our objective in this study was to determine the prevalence and trend of developing B-lines at 2,745 meters above sea level among healthy visitors over four consecutive days. METHODS: We performed a prospective case series on healthy volunteers at Mammoth Mountain, CA, USA. Subjects underwent pulmonary ultrasound for B-lines over four consecutive days. RESULTS: We enrolled 21 male and 21 female participants. There was an increase in the sum of B-lines at both lung bases from day 1 to day 3, with a subsequent decrease from day 3 to day 4(P<0.001). By the third day at altitude, B-lines were detectable at base of lungs of all participants. Similarly, B-lines increased at apex of lungs from day 1 to day 3 and decreased on day 4 (P=0.004). CONCLUSION: By the third day at 2,745 meters altitude, B-lines were detectable in the bases of both lungs of all healthy participants in our study. We assume that increasing the number of B-lines could be considered an early sign of HAPE. Point-of-care ultrasound could be used to detect and monitor B-lines at altitude to facilitate early detection of HAPE, regardless of pre-existing risk factors.

Serratus anterior plane block as a bridge to outpatient management of severe rib fractures: a case report.

Rib fractures account for a significant number of emergency department visits each year. A patient's disposition often depends on the severity of rib fractures, comorbidities, and ability to achieve adequate analgesia. We present a 44-year-old male patient with severe pain secondary to rib fractures. The initial disposition was to admit for pain control. However, upon performing a serratus anterior plane block, patient was functionally appropriate for discharge with proper return precautions. Serratus anterior plane block is within the skillset of the emergency physician and can be used to achieve analgesia for rib fractures without the sedative and respiratory depressive effects associated with opioids.

A Case Report of Epiglottitis in an Adult Patient.

Epiglottitis is historically known to be a disease of childhood. However, since the implementation of the Haemophilus influenzae type B vaccination, there has been an increasing incidence within the adult population. This is a case report of a 36-year-old male who presented to the emergency department (ED) in severe respiratory distress with complaints of a sore throat, shortness of breath, odynophagia, dysphagia, and hoarseness. Physical exam revealed biphasic stridor, tachycardia, tachypnea, and an erythematous uvula. Imaging of his neck revealed findings consistent with epiglottitis containing nonspecific air. The patient was rapidly intubated, started on broad spectrum antibiotics and dexamethasone. He was admitted for intensive medical management with Otolaryngology consultation. This case report highlights the importance of rapid recognition and diagnosis of epiglottitis in an adult population to prevent morbidity and mortality. Topics: Epiglottitis, stridor, odynophagia, dysphagia, Haemophilus influenzae, group C streptococci, thumb-print sign, intubation.