Test performance of point-of-care ultrasound for gastric content.

OBJECTIVE: We sought to determine test performance characteristics of emergency physician ultrasound for the identification of gastric contents. METHODS: Subjects were randomized to fast for at least 10 h or to consume food and water. A sonologist blinded to the patient's status performed an ultrasound of the stomach 10 min after randomization and oral intake, if applicable. The sonologist recorded their interpretation of the study using three sonographic windows. Subsequently 2 emergency physicians reviewed images of each study and provided an interpretation of the examination. Test performance characteristics and inter-rater agreement were calculated. RESULTS: 45 gastric ultrasounds were performed. The sonologist had excellent sensitivity (92%; 95% CI 73%-99%) and specificity (85%; 95% CI 62%-92%). Expert review demonstrated excellent sensitivity but lower specificity. Inter-rater agreement was very good (κ = 0.64, 95%CI 0.5-0.78). CONCLUSION: Emergency physician sonologists were sensitive but less specific at detecting stomach contents using gastric ultrasound.

Ultrasonography versus computed tomography for suspected nephrolithiasis.

BACKGROUND: There is a lack of consensus about whether the initial imaging method for patients with suspected nephrolithiasis should be computed tomography (CT) or ultrasonography. METHODS: In this multicenter, pragmatic, comparative effectiveness trial, we randomly assigned patients 18 to 76 years of age who presented to the emergency department with suspected nephrolithiasis to undergo initial diagnostic ultrasonography performed by an emergency physician (point-of-care ultrasonography), ultrasonography performed by a radiologist (radiology ultrasonography), or abdominal CT. Subsequent management, including additional imaging, was at the discretion of the physician. We compared the three groups with respect to the 30-day incidence of high-risk diagnoses with complications that could be related to missed or delayed diagnosis and the 6-month cumulative radiation exposure. Secondary outcomes were serious adverse events, related serious adverse events (deemed attributable to study participation), pain (assessed on an 11-point visual-analogue scale, with higher scores indicating more severe pain), return emergency department visits, hospitalizations, and diagnostic accuracy. RESULTS: A total of 2759 patients underwent randomization: 908 to point-of-care ultrasonography, 893 to radiology ultrasonography, and 958 to CT. The incidence of high-risk diagnoses with complications in the first 30 days was low (0.4%) and did not vary according to imaging method. The mean 6-month cumulative radiation exposure was significantly lower in the ultrasonography groups than in the CT group (P<0.001). Serious adverse events occurred in 12.4% of the patients assigned to point-of-care ultrasonography, 10.8% of those assigned to radiology ultrasonography, and 11.2% of those assigned to CT (P=0.50). Related adverse events were infrequent (incidence, 0.4%) and similar across groups. By 7 days, the average pain score was 2.0 in each group (P=0.84). Return emergency department visits, hospitalizations, and diagnostic accuracy did not differ significantly among the groups. CONCLUSIONS: Initial ultrasonography was associated with lower cumulative radiation exposure than initial CT, without significant differences in high-risk diagnoses with complications, serious adverse events, pain scores, return emergency department visits, or hospitalizations. (Funded by the Agency for Healthcare Research and Quality.).

Point-of-Care Ultrasound Use, Accuracy, and Impact on Clinical Decision Making in Rwanda Hospitals.

OBJECTIVES: Few studies of point-of-care ultrasound training and use in low resource settings have reported the impact of examinations on clinical management or the longer-term quality of trainee-performed studies. We characterized the long-term effect of a point-of-care ultrasound program on clinical decision making, and evaluated the quality of clinician-performed ultrasound studies. METHODS: We conducted point-of-care ultrasound training for physicians from Rwandan hospitals. Physicians then used point-of-care ultrasound and recorded their findings, interpretation, and effects on patient management. Data were collected for 6 months. Trainee studies were reviewed for image quality and accuracy. RESULTS: Fifteen participants documented 1158 ultrasounds; 590 studies (50.9%) had matched images and interpretations for review. Abdominal ultrasound for free fluid was the most frequently performed application. The mean image quality score was 2.36 (95% confidence interval, 2.28-2.44). Overall sensitivity and specificity for trainee-performed examinations was 94 and 98%. Point-of-care ultrasound use most commonly changed medications administered (42.4%) and disposition (30%). CONCLUSIONS: A point-of-care ultrasound training intervention in a low-resource setting resulted in high numbers of diagnostic-quality studies over long-term follow-up. Ultrasound use routinely changed clinical decision making.

Intensive point-of-care ultrasound training with long-term follow-up in a cohort of Rwandan physicians.

OBJECTIVE: We delivered a point-of-care ultrasound training programme in a resource-limited setting in Rwanda, and sought to determine participants' knowledge and skill retention. We also measured trainees' assessment of the usefulness of ultrasound in clinical practice. METHODS: This was a prospective cohort study of 17 Rwandan physicians participating in a point-of-care ultrasound training programme. The follow-up period was 1 year. Participants completed a 10-day ultrasound course, with follow-up training delivered over the subsequent 12 months. Trainee knowledge acquisition and skill retention were assessed via observed structured clinical examinations (OSCEs) administered at six points during the study, and an image-based assessment completed at three points. RESULTS: Trainees reported minimal structured ultrasound education and little confidence using point-of-care ultrasound before the training. Mean scores on the image-based assessment increased from 36.9% (95% CI 32-41.8%) before the initial 10-day training to 74.3% afterwards (95% CI 69.4-79.2; P < 0.001). The mean score on the initial OSCE after the introductory course was 81.7% (95% CI 78-85.4%). The mean OSCE performance at each subsequent evaluation was at least 75%, and the mean OSCE score at the 58-week follow up was 84.9% (95% CI 80.9-88.9%). CONCLUSIONS: Physicians providing acute care in a resource-limited setting demonstrated sustained improvement in their ultrasound knowledge and skill 1 year after completing a clinical ultrasound training programme. They also reported improvements in their ability to provide patient care and in job satisfaction.

Predicting ureteral stones in emergency department patients with flank pain: an external validation of the STONE score.

PURPOSE: The ability to objectively predict which emergency department patients are likely to have a ureteral stone may aid in cost-effectiveness and patient-centered diagnostic imaging decisions. We performed an external validation of the STONE score, a clinical prediction rule for the presence of uncomplicated ureteral stones in emergency department patients developed at Yale University School of Medicine. METHODS: Five hundred thirty-six (536) consecutive patients evaluated in an urban tertiary care emergency department for the possible diagnosis of ureteral stone were retrospectively reviewed. The STONE score uses five factors (gender, duration of pain, race, nausea/vomiting, erythrocytes on urine dipstick) to categorize patients into low, medium, and high probability of having a ureteral stone. The total STONE score risk is 0-13 and divided into three groups: low risk = 0-5, moderate risk = 6-9, and high risk = 10-13. RESULTS: Of the 536 patients evaluated for suspected ureteral stone, 257 (47.8 %) had a ureteral stone. Mean patient age was 45.9 years (SD 16.3), and gender distribution was 43.9 % female and 56.1 % male. Distribution of STONE score risk was 24.1 % low, 48.1 % moderate, and 27.7 % high. Diagnosis of ureteral stone by STONE score risk was 14 % for low-risk group, 48.3 % for moderate-risk group, and 75.8 % for high-risk group. This distribution is consistent with internal validation at Yale University School of Medicine, where values were 8.3-9.2 % for low risk, 51.3-51.6 % for moderate risk, and 88.6-89.6 % for high risk. CONCLUSIONS: Our study validates the use of the STONE clinical score to categorize patients as low, moderate, and high risk for ureteral stone. This could help guide development of clinical decision rules for diagnostic studies and imaging in the future.

Can ureteral stones cause pain without causing hydronephrosis?

INTRODUCTION: While computerized tomography (CT) is the gold standard for diagnosis of ureterolithiasis, ultrasound is a less costly and radiation-free alternative which is commonly used to evaluate patients with ureteral colic. The purpose of this study was to evaluate the frequency with which patients with ureteral stones and renal colic demonstrate hydronephrosis in order to better understand the evaluation of these patients. METHODS: Two hundred and forty-eight consecutive patients presenting with ureteral colic and diagnosed with a single unilateral ureteral stone on CT scan in an urban tertiary care emergency department were retrospectively reviewed. Radiology reports were reviewed for stone size, diagnosis, and degree of hydronephrosis. RESULTS: Of the 248 patients evaluated for suspected ureteral stone, 221 (89.1 %) demonstrated any hydronephrosis, while 27 (10.9 %) did not. Hydronephrosis grade, available in 194 patients, was as follows: mild-70.6 %, moderate-27.8 %, and severe-1.5 %. Mean patient age was 47.0 years (SD 15.5), gender distribution was 35.9 % female and 64.1 % male, and mean stone axial diameter was 4.1 mm (SD 2.4). Stone location was as follows: ureteropelvic junction-4.1 %, proximal ureter-21 %, distal ureter-24.9 %, and ureterovesical junction-47.1 %. Axial stone diameter and coronal length (craniocaudal) were both significant predictors of degree of hydronephrosis (ANOVA, p < 0.001 for both). Age (ANOVA, p = NS), stone location (Chi square, p = NS), and gender (Chi square, p = NS) were not associated with degree of hydronephrosis. CONCLUSIONS: In patients with ureteral stones and colic, nearly 11 % do not demonstrate any hydronephrosis and a majority (nearly 71 %) will demonstrate only mild hydronephrosis. Stone diameter appears to be related to degree of hydronephrosis, whereas age, gender, and stone location are not. The lower incidence of hydronephrosis for small stones causing renal colic may explain the lower diagnostic accuracy of ultrasound when compared to CT for detecting ureteral stones.

Carotid Flow Time Changes With Volume Status in Acute Blood Loss.

STUDY OBJECTIVE: Noninvasive predictors of volume responsiveness may improve patient care in the emergency department. Doppler measurements of arterial blood flow have been proposed as a predictor of volume responsiveness. We seek to determine the effect of acute blood loss and a passive leg raise maneuver on corrected carotid artery flow time. METHODS: In a prospective cohort of blood donors, we obtained a Doppler tracing of blood flow through the carotid artery before and after blood loss. Measurements of carotid flow time, cardiac cycle time, and peak blood velocity were obtained in supine position and after a passive leg raise. Measurements of flow time were corrected for pulse rate. RESULTS: Seventy-nine donors were screened for participation; 70 completed the study. Donors had a mean blood loss of 452 mL. Mean corrected carotid artery flow time before blood loss was 320 ms (95% confidence interval [CI] 315 to 325 ms); this decreased after blood loss to 299 ms (95% CI 294 to 304 ms). A passive leg raise had little effect on mean corrected carotid artery flow time before blood loss (mean increase 4 ms; 95% CI -1 to 9 ms), but increased mean corrected carotid artery flow time after blood loss (mean increase 23 ms; 95% CI 18 to 28 ms) to predonation levels. CONCLUSION: Corrected carotid artery flow time decreased after acute blood loss. In the setting of acute hypovolemia, a passive leg raise restored corrected carotid artery flow time to predonation levels. Further investigation of corrected carotid artery flow time as a predictor of volume responsiveness is warranted.

The irregular diaphragmatic pleural interface: a novel sonographic sign facilitating the diagnosis of pneumonia.

Pneumonia, a disease that has been reported to be the sixth leading cause of death in the United States, has worsening mortality with delays in diagnosis. As the history and physical examination are excessively inaccurate in the diagnosis of pneumonia, we often rely on chest radiography to rule in or out disease. However, it is found to lack sufficient accuracy when computed tomography is used as the reference standard. Sonography has emerged as a viable alternative to chest radiography in the diagnosis of pneumonia. Here, we describe a novel sonographic sign that can be used to assist in the diagnosis of pneumonia.

A practical guide to self-sustaining point-of-care ultrasound education programs in resource-limited settings.

The value of point-of-care ultrasound education in resource-limited settings is increasingly recognized, though little guidance exists on how to best construct a sustainable training program. Herein we offer a practical overview of core factors to consider when developing and implementing a point-of-care ultrasound education program in a resource-limited setting. Considerations include analysis of needs assessment findings, development of locally relevant curriculum, access to ultrasound machines and related technological and financial resources, quality assurance and follow-up plans, strategic partnerships, and outcomes measures. Well-planned education programs in these settings increase the potential for long-term influence on clinician skills and patient care.

Diagnosis of megaureter by point-of-care ultrasound.

BACKGROUND: Presentation of congenital megaureter in adult life is rare; patients usually become symptomatic in childhood. CASE REPORT: A 32-year-old man presented to the Emergency Department (ED) with dyspnea, tongue swelling, and a rash, which he attributed to amoxicillin he had taken shortly prior to onset of symptoms. He was hypotensive on arrival to the ED. To further evaluate the hypotension, point-of-care ultrasound of the heart, lungs, and abdomen were performed while treatment for anaphylaxis was initiated. Ultrasound examination did not identify a cause for hypotension, but the treating physician noted an anechoic structural abnormality posterior to the bladder, suggestive of megaureter. The patient responded well to treatment of anaphylaxis; further history and diagnostic imaging subsequently confirmed a diagnosis of congenital megaureter. CONCLUSION: We report an unusual case of congenital megaureter, identified by point-of-care ultrasound performed to evaluate hypotension. Clinicians performing limited ultrasound examinations must be attentive to incidental findings that will require follow-up.

Bedside ultrasound maximizes patient satisfaction.

BACKGROUND: Bedside ultrasound (US) is associated with improved patient satisfaction, perhaps as a consequence of improved time to diagnosis and decreased length of stay (LOS). OBJECTIVES: Our study aimed to quantify the association between beside US and patient satisfaction and to assess patient attitudes toward US and perception of their interaction with the clinician performing the examination. METHODS: We enrolled a convenience sample of adult patients who received a bedside US. The control group had similar LOS and presenting complaints but did not have a bedside US. Both groups answered survey questions during their emergency department (ED) visit and again by telephone 1 week later. The questionnaire assessed patient perceptions and satisfaction on a 5-point Likert scale. RESULTS: Seventy patients were enrolled over 10 months. The intervention group had significantly higher scores on overall ED satisfaction (4.69 vs. 4.23; mean difference 0.46; 95% confidence interval [CI] 0.17-0.75), diagnostic testing (4.54 vs. 4.09; mean difference 0.46; 95% CI 0.16-0.76), and skills/abilities of the emergency physician (4.77 vs. 4.14; mean difference 0.63; 95% CI 0.29-0.96). A trend to higher scores for the intervention group persisted on follow-up survey. CONCLUSIONS: Patients who had a bedside US had statistically significant higher satisfaction scores with overall ED care, diagnostic testing, and with their perception of the emergency physician. Bedside US has the potential not only to expedite care and diagnosis, but also to maximize satisfaction scores and improve the patient-physician relationship, which has increasing relevance to health care organizations and hospitals that rely on satisfaction surveys.

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.

Faculty staff-guided versus self-guided ultrasound training for internal medicine residents.

OBJECTIVES: Ultrasonography is of growing importance within internal medicine (IM), but the optimal method of training doctors to use it is uncertain. In this study, the authors provide the first objective comparison of two approaches to training IM residents in ultrasonography. METHODS: In this randomised trial, a simulation-based ultrasound training curriculum was implemented during IM intern orientation at a tertiary care teaching hospital. All 72 incoming interns attended a lecture and were given access to online modules. Interns were then randomly assigned to a 4-hour faculty-guided (FG) or self-guided (SG) ultrasound training session in a simulation laboratory with both human and manikin models. Interns were asked to self-assess their competence in ultrasonography and underwent an objective structured clinical examination (OSCE) to assess their competence in basic and procedurally oriented ultrasound tasks. The primary outcome was the score on the OSCE. RESULTS: Faculty-guided training was superior to self-guided training based on the OSCE scores. Subjects in the FG training group achieved significantly higher OSCE scores on the two subsets of task completion (0.9-point difference, 95% confidence interval [CI] 0.27-1.54; p = 0.008) and ultrasound image quality (2.43-point difference, 95% CI 1.5-3.36; p < 0.001). Both training groups demonstrated an increase in self-assessed competence after their respective training sessions and there was little difference between the groups. Subjects rated the FG training group much more favourably than the SG training group. CONCLUSIONS: Both FG and SG ultrasound training curricula can improve the self-reported competence of IM interns in ultrasonography. However, FG training was superior to SG training in both skills acquisition and intern preference. Incorporating mandatory ultrasound training into IM residencies can address the perceived need for ultrasound training, improve confidence and procedural skills, and may enhance patient safety. However, the optimal training method may require significant faculty input.

Automated B-line scoring on thoracic sonography.

With the proliferation of portable sonography and the increase in nontraditional users, there is an increased need for automated decision support to standardize results. We developed algorithms to evaluate the presence or absence of "B-lines" on thoracic sonography as a marker for interstitial fluid. Algorithm performance was compared against an average of scores from 2 expert clinical sonographers. On the set for algorithm development, 90% of the scores matched the average expert scores with differences of 1 or less. On the independent set, a perfect match was achieved. We believe that these are the first reported results in computerized B-line scoring.

Emergency ultrasound diagnosis of ovarian hyperstimulation syndrome: case report.

BACKGROUND: Ovarian hyperstimulation syndrome (OHSS) is an exaggerated response to ovulation induction therapy. It is a known complication of ovarian stimulation in patients undergoing treatment for infertility. As assisted reproductive technology and the use of ovulation induction agents expands, it is likely that there will be more cases of OHSS presenting to the Emergency Department (ED). OBJECTIVES: OHSS has a broad spectrum of clinical manifestations, from mild abdominal pain to severe cases where there is increased vascular permeability leading to significant fluid accumulation in body cavities and interstitial space. Severe cases may present to the ED with ascites, pericardial effusions, pleural effusions, and lower extremity edema. Through a case report, we review OHSS with an emphasis on early diagnosis by Emergency Physician (EP)-performed bedside ultrasonography. CASE REPORT: We present a case of a patient undergoing treatment for infertility who presented to the ED with shortness of breath and abdominal pain. The diagnosis of severe OHSS was made, largely based on EP-performed bedside ultrasonography showing peritoneal free fluid and bilateral pleural effusions, as well as multiple ovarian follicles. CONCLUSIONS: This report reviews the pathophysiology of OHSS, its clinical features, and pertinent diagnostic and management issues. This report emphasizes the importance of early EP-performed bedside ultrasonography.

Using lung ultrasound to differentiate patients in acute dyspnea in the prehospital emergency setting.

The diagnosis and treatment of dyspnea in the emergency department and in the prehospital setting is a challenge faced by the emergency physician and other prehospital care providers. While the use of lung ultrasound as a diagnostic tool in dyspneic patients has been well researched, there has been limited evaluation of its use in the prehospital setting. In the previous issue of Critical Care, Prosen and colleagues study the accuracy of lung ultrasound compared with both N-terminal pro-brain natriuretic peptide and the clinical examination for differentiating between acute decompensated congestive heart failure and chronic obstructive pulmonary disease exacerbations for patients in the prehospital setting. Their article adds to the growing body of evidence demonstrating the diagnostic efficacy of lung ultrasound in differentiating between these two disease processes in the acutely dyspneic patient.

Real-time video streaming of sonographic clips using domestic internet networks and free videoconferencing software.

OBJECTIVES: As the use of point-of-care sonography spreads, so too does the need for remote expert over-reading via telesonogrpahy. We sought to assess the feasibility of using familiar, widespread, and cost-effective existent technology to allow remote over-reading of sonograms in real time and to compare 4 different methods of transmission and communication for both the feasibility of transmission and image quality. METHODS: Sonographic video clips were transmitted using 2 different connections (WiFi and 3G) and via 2 different videoconferencing modalities (iChat [Apple Inc, Cupertino, CA] and Skype [Skype Software Sàrl, Luxembourg]), for a total of 4 different permutations. The clips were received at a remote location and recorded and then scored by expert reviewers for image quality, resolution, and detail. RESULTS: Wireless transmission of sonographic clips was feasible in all cases when WiFi was used and when Skype was used over a 3G connection. Images transmitted via a WiFi connection were statistically superior to those transmitted via 3G in all parameters of quality (average P = .031), and those sent by iChat were superior to those sent by Skype but not statistically so (average P = .057). CONCLUSIONS: Wireless transmission of sonographic video clips using inexpensive hardware, free videoconferencing software, and domestic Internet networks is feasible with retention of image quality sufficient for interpretation. WiFi transmission results in greater image quality than transmission by a 3G network.

Use of Critical Items in Determining Point-of-Care Ultrasound Competence.

We previously developed a workplace-based tool for assessing point of care ultrasound (POCUS) skills and used a modified Delphi technique to identify critical items (those that learners must successfully complete to be considered competent). We performed a standard setting procedure to determine cut scores for the full tool and a focused critical item tool. This study compared ratings by 24 experts on the two checklists versus a global entrustability rating. All experts assessed three videos showing an actor performing a POCUS exam on a patient. The performances were designed to show a range of competences and one included potentially critical errors. Interrater reliability for the critical item tool was higher than for the full tool (intraclass correlation coefficient = 0.84 [95% confidence interval [CI] 0.42-0.99] vs. 0.78 [95% CI 0.25-0.99]). Agreement with global ratings of competence was higher for the critical item tool (κ = 0.71 [95% CI 0.55-0.88] vs 0.48 [95% CI 0.30-0.67]). Although sensitivity was higher for the full tool (85.4% [95% CI 72.2-93.9%] vs. 81.3% [95% CI 67.5-91.1%]), specificity was higher for the critical item tool (70.8% [95% CI 48.9-87.4%] vs. 29.2% [95% CI 12.6-51.1%]). We recommend the use of critical item checklists for the assessment of POCUS competence.