Does Point-of-Care Ultrasound Affect Fluid Resuscitation Volume in Patients with Septic Shock: A Retrospective Review

Background

Fixed, large volume resuscitation with intravenous fluids (IVFs) in septic shock can cause inadvertent hypervolemia, increased medical interventions, and death when unguided by point-of-care ultrasound (POCUS). The primary study objective was to evaluate whether total IVF volume differs for emergency department (ED) septic shock patients receiving POCUS versus no POCUS.

Methods

We conducted a retrospective observational cohort study from 7/1/2018 to 8/31/2021 of atraumatic adult ED patients with septic shock. We agreed upon a priori variables and defined septic shock as lactate ≥4 and hypotension (SBP <90 or MAP <65). A sample size of 300 patients would provide 85% power to detect an IVF difference of 500 milliliters between POCUS and non-POCUS cohorts. Data are reported as frequencies, median (IQR), and associations from bivariate logistic models.

Results

304 patients met criteria and 26% (78/304) underwent POCUS. Cardiac POCUS demonstrated reduced ejection fraction in 15.4% of patients. Lung ultrasound showed normal findings in 53% of patients. The POCUS vs. non-POCUS cohorts had statistically significant differences for the following variables: higher median lactate (6.7 [IQR 5.2-8.7] vs. 5.6], p = 0.003), lower systolic blood pressure (77.5 [IQR 61-86] vs. 85.0, p < 0.001), more vasopressor use (51% vs. 34%, p = 0.006), and more positive pressure ventilation (38% vs. 24%, p = 0.017). However, there were no statistically significant differences between POCUS and non-POCUS cohorts in total IVF volume ml/kg (33.02 vs. 32.1, p = 0.47), new oxygen requirement (68% vs. 59%, p = 0.16), ED death (3% vs. 4%, p = 0.15), or hospital death (31% vs. 27%, p = 0.48). There were similar distributions of lactate, total fluids, and vasopressors in patients with CHF and severe renal failure.

Conclusions

Among ED patients with septic shock, POCUS was more likely to be used in sicker patients. Patients who had POCUS were given similar volume of crystalloids although these patients were more critically ill. There were no differences in new oxygen requirement or mortality in the POCUS group compared to the non-POCUS group.

Adverse events related to ultrasound-guided regional anesthesia performed by Emergency Physicians: Systematic review protocol

The use of ultrasound-guided regional anesthesia for pain management has become increasingly prevalent in Emergency Medicine, with studies noting excellent pain control while sparing opioid use. However, the use of ultrasound-guided regional anesthesia may be hampered by concern about risks for patient harm. This systematic review protocol describes our approach to evaluate the incidence of adverse events from the use of ultrasound-guided regional anesthesia by Emergency Physicians as described in the literature. This project will also seek to document the scope of ultrasound-guided regional anesthesia applications being performed in Emergency Medicine literature, and potentially serve as a framework for future systematic reviews evaluating adverse events in Emergency Medicine.

Comparison of outcomes between pulseless electrical activity by electrocardiography and pulseless myocardial activity by echocardiography in out-of-hospital cardiac arrest; secondary analysis from a large, prospective study

OBJECTIVE

To measure prevalence of discordance between electrical activity recorded by electrocardiography (ECG) and myocardial activity visualized by echocardiography (echo) in patients presenting after cardiac arrest and to compare survival outcomes in cohorts defined by ECG and echo.

METHODS

This is a secondary analysis of a previously published prospective study at twenty hospitals. Patients presenting after out-of-hospital arrest were included. The cardiac electrical activity was defined by ECG and contemporaneous myocardial activity was defined by bedside echo. Myocardial activity by echo was classified as myocardial asystole--the absence of myocardial movement, pulseless myocardial activity (PMA)--visible myocardial movement but no pulse, and myocardial fibrillation--visualized fibrillation. Primary outcome was the prevalence of discordance between electrical activity and myocardial activity.

RESULTS

793 patients and 1943 pauses in CPR were included. 28.6% of CPR pauses demonstrated a difference in electrical activity (ECG) and myocardial activity (echo), 5.0% with asystole (ECG) and PMA (echo), and 22.1% with PEA (ECG) and myocardial asystole (echo). Twenty-five percent of the 32 pauses in CPR with a shockable rhythm by echo demonstrated a non-shockable rhythm by ECG and were not defibrillated. Survival for patients with PMA (echo) was 29.1% (95%CI-23.9-34.9) compared to those with PEA (ECG) (21.4%, 95%CI-17.7-25.6).

CONCLUSION

Patients in cardiac arrest commonly demonstrate different electrical (ECG) and myocardial activity (echo). Further research is needed to better define cardiac activity during cardiac arrest and to explore outcome between groups defined by electrical and myocardial activity.

Quantitative characterization of left ventricular function during pulseless electrical activity using echocardiography during out-of-hospital cardiac arrest

BACKGROUND

Several prospective studies have demonstrated that the echocardiographic detection of any myocardial activity during PEA is strongly associated with higher rates of return of spontaneous circulation (ROSC). We hypothesized that PEA represents a spectrum of disease in which not only the presence of myocardial activity, but more specifically that the degree of left ventricular (LV) function would be a predictor of outcomes. The purpose of this study was to retrospectively assess the association between LV function and outcomes in patients with OHCA.

MATERIALS AND METHODS

Using prospectively obtained data from an observational cohort of patients receiving focused echocardiography during cardiopulmonary resuscitation (CPR) in the Emergency Department (ED) setting, we analyzed 312 consecutive subjects with available echocardiography images with initial rhythm of PEA. We used left ventricular systolic fractional shortening (LVFS), a unidimensional echocardiographic parameter to perform the quantification of LV function during PEA. Regression analyses were performed independently to evaluate for relationships between LVFS and a primary outcome of ROSC and secondary outcome of survival to hospital admission. We analyzed LVFS both as a continuous variable and as a categorial variable using the quartiles and the median to perform multiple different comparisons and to illustrate the relationship of LVFS and outcomes of interest. We performed survival analysis using Cox proportional hazards model to evaluate the hazard corresponding to length of resuscitation.

RESULTS

We found a positive association between LVFS and the primary outcome of ROSC (OR 1.04, 95%CI 1.01-1.08), but not with the secondary outcome of survival to hospital admission (OR 1.02, 95%CI 0.96-1.08). Given that the relationship was not linear and that we observed a threshold effect in the relationship between LVFS and outcomes, we performed an analysis using quartiles of LVFS. The predicted probability of ROSC was 75% for LVFS between 23.4-96% (fourth quartile) compared to 47% for LVFS between 0-4.7% (first quartile). The hazard of not achieving ROSC was significantly greater for subjects with LVFS below the median (13.1%) compared to the subgroup with LVFS greater than 13.1% (p < 0.05), with the separation of the survival curves occurring at approximately 40 min of resuscitation duration.

CONCLUSIONS

Left ventricular function measured by LVFS is positively correlated with higher probability of ROSC and may be associated with higher chances of survival in patients with PEA arrest.

Sex-related differences in D-dimer levels for venous thromboembolism screening

BACKGROUND

D-dimer is generally considered positive above 0.5 mg/L irrespective of sex. However, women have been shown to be more likely to have a positive D-dimer after controlling for other factors. Thus, differences may exist between males and females for using D-dimer as a marker of venous thromboembolic (VTE) disease. We hypothesized that the accuracy of D-dimer tests may be enhanced by using appropriate cutoff values that reflect sex-related differences in D-dimer levels.

METHODS

This research is a secondary analysis of a multicenter, international, prospective, observational study of adult (18+ years) patients suspected of VTE, with low-to-intermediate pretest probability based on Wells criteria ≤ 6 for pulmonary embolism (PE) and ≤ 2 for deep vein thrombosis (DVT). VTE diagnoses were based on computed tomography, ventilation perfusion scanning, or venous ultrasound. D-dimer levels were tested for statistical difference across groups stratified by sex and diagnosis. Multivariable regression was used to investigate sex as a predictor of diagnosis. Sex-specific optimal D-dimer thresholds for PE and DVT were calculated from receiver operating characteristic analyses. A Youden threshold (D-dimer level coinciding with the maximum of sensitivity plus specificity) and a cutoff corresponding to 95% sensitivity were calculated. Statistical difference for cutoffs was tested via 95% confidence intervals from 2,000 bootstrapped samples.

RESULTS

We included 3,586 subjects for analysis, of whom 61% were female. Race demographics were 63% White, 27% Black/African American, and 6% Hispanic. In the suspected PE cohort, 6% were diagnosed with PE, while in the suspected DVT cohort, 11% were diagnosed with DVT. D-dimer levels were significantly higher in males than females for the PE-positive group and the DVT-negative group, but males had significantly lower D-dimer levels than females in the PE-negative group. Regression models showed male sex as a significant positive predictor of DVT diagnosis, controlling for D-dimer levels. The Youden thresholds for PE patients were 0.97 (95% CI = 0.64 to 1.79) mg/L and 1.45 (95% CI = 1.36 to 1.95) mg/L for females and males, respectively; 95% sensitivity cutoffs for this group were 0.64 (95% CI = 0.20 to 0.89) and 0.55 (95% CI = 0.29 to 1.61). For DVT, the Youden thresholds were 0.98 (95% CI = 0.84 to 1.56) mg/L for females and 1.25 (95% CI = 0.65 to 3.33) mg/L for males with 95% sensitivity cutoffs of 0.33 (95% CI = 0.2 to 0.61) and 0.32 (95% CI = 0.18 to 0.7), respectively.

CONCLUSION

Differences in D-dimer levels between males and females are diagnosis specific; however, there was no significant difference in optimal cutoff values for excluding PE and DVT between the sexes.

Evaluation of Gender Differences in Ultrasound Milestone Evaluations During Emergency Medicine Residency Training: A Multicenter Study

OBJECTIVES

Prior literature has demonstrated incongruities among faculty evaluation of male and female residents' procedural competency during residency training. There are no known studies investigating gender differences in the assessment of procedural skills among emergency medicine (EM) residents, such as those required by ultrasound. The objective of this study was to determine if there are significant gender differences in ultrasound milestone evaluations during EM residency training.

METHODS

We used a stratified, random cluster sample of Accreditation Council for Graduate Medical Education (ACGME) EM residency programs to conduct a longitudinal, retrospective cohort analysis of resident ultrasound milestone evaluation data. Milestone evaluation data were collected from a total of 16 ACGME-accredited EM residency programs representing a 4-year period. We stratified milestone data by resident gender, date of evaluation, resident postgraduate year, and cohort (residents with the same starting date).

RESULTS

A total of 2,554 ultrasound milestone evaluations were collected from 1,187 EM residents (750 men [62.8%] and 444 women [37.1%]) by 104 faculty members during the study period. There was no significant overall difference in mean milestone score between female and male residents [mean difference = 0.01 (95% confidence interval {CI} = -0.04 to 0.05)]. There were no significant differences between female and male residents' mean milestone scores at the first (baseline) PGY1 evaluation (mean difference = -0.04 [95% CI = -0.09 to 0.003)] or at the final evaluation during PGY3 (mean difference = 0.02 [95% CI = -0.03 to 0.06)].

CONCLUSIONS

Despite prior studies suggesting gender bias in the evaluation of procedural competency during residency training, our study indicates that there were no significant gender-related differences in the ultrasound milestone evaluations among EM residents within training programs throughout the United States.

A retrospective study of pulseless electrical activity, bedside ultrasound identifies interventions during resuscitation associated with improved survival to hospital admission. A REASON Study

OBJECTIVE

Our objective was to determine whether organized or disorganized cardiac activity is associated with increased survival in patients who present in pulseless electrical activity (PEA) treated with either 1) standard advanced cardiac life support (ACLS) medications or 2) other interventions.

METHODS

This was a secondary analysis of a prospective, multi-center observational study utilizing ultrasound in out-of-hospital or inemergency department PEA arrest. Bedside ultrasound was performed as ACLS protocol started and during pulse checks. Only cases with visible cardiac activity on ultrasound were included in the present analysis. Cardiac activity was categorized as disorganized (agonal twitching) or organized (contractions with changes in ventricular dimensions). Patients were categorized as receiving either standard bolus ACLS medications or alternative medications during the resuscitation (continuous adrenergic agents, thrombolytics, others). The primary outcome was survival to hospital admission. The secondary outcome was return of spontaneous circulation (ROSC). Multivariate modeling was performed to assess association between survival to hospital admission in patients with intravenous adrenergic agents and cardiac activity.

RESULTS

In our cohort of 225 patients in PEA cardiac arrest with cardiac activity on ultrasound, the overall survival rate was higher in patients with organized cardiac activity than with disorganized cardiac activity. PEA cardiac arrest patients with organized cardiac activity treated with standard ACLS interventions demonstrated improved survival to hospital admission compared to those with disorganized activity (37.7% (95%CI 24.8-50.2%) versus 17.9% (95%CI 10.9-28%). PEA cardiac arrest patients with organized cardiac activity who received continuous adrenergic agents during the resuscitation and prior to ROSC demonstrated higher survival to hospital admission 45.5% (95%CI 26.9-65.4%) and ROSC 90.9% (95%CI 71.0-98.7%) compared to those with disorganized cardiac activity who received continuous adrenergic agents during the resuscitation 0% (95%CI 0-23.0%) and 47.1% (95%CI 26-69%). Regression analysis demonstrates an association between increased survival in patients receiving intravenous adrenergic agents and organized cardiac activity.

CONCLUSION

Survival in patients following PEA arrest is higher in patients with organized cardiac activity. The initiation of continuous adrenergic agents during PEA was associated with improved survival to hospital admission in patients with organized cardiac activity on bedside ultrasound, but this improvement was not seen in patients in PEA with disorganized cardiac activity. Bedside ultrasound may identify a subset of patients that respond differently to ACLS interventions.

Treated-and-released urinary catheterization in the emergency department by sex

BACKGROUND

The prevalence and difference in likely indications of urinary catheterization (UC) in treated-and-released emergency department (ED) visits between men and women are currently unknown.

METHODS

This was a cross-sectional analysis using the 2013 National Emergency Department Sample for all treated-and-released visits in persons aged ≥18 years. The prevalence of conditions associated with UC visits in men and women were identified. A hierarchical ranking was used to categorize diagnosis codes identified during ED visits into clinically meaningful categories to assess conditions for UC.

RESULTS

In 2013, there were 87,797,062 treated-and-released ED visits in adults. The rate of UC in treated-and-released ED visits in adults was 4.3 per 1,000 visits, with 6.5 per 1,000 visits in men and 2.7 per 1,000 visits in women. Using the hierarchal ranking, a higher proportion of UC visits in men were coded for acute urinary retention, and a higher proportion of UC visits in women were coded for neurologic, cognitive, and psychiatric conditions.

CONCLUSIONS

The rate of UC in treated-and-released ED visits was higher in men than women, and UC rate increased with age. The heterogeneity of conditions coded in UC visits in women compared with men may suggest more potentially avoidable UC in women in the treated-and-released ED population. If confirmed, this would suggest opportunities for quality improvement in the ED to prevent overutilization of urinary catheters.

Central Venous Catheterization: Are We Using Ultrasound Guidance?

OBJECTIVES

To assess the self-reported frequency of use of ultrasound guidance for central venous catheterization by emergency medicine (EM) residents, describe residents' perceptions regarding the use of ultrasound guidance, and identify barriers to the use of ultrasound guidance.

METHODS

A longitudinal cross-sectional study was conducted at 5 academic institutions. A questionnaire on the use of ultrasound guidance for central venous catheterization was initially administered to EM residents in 2007. The same questionnaire was distributed again in the 5 EM residency programs in 2013.

RESULTS

In 2007 and 2013, 147 and 131 residents completed questionnaires, respectively. A significant increase in the use of ultrasound guidance for central venous catheterization was reported in 2013 compared to 2007 (P< .001). In 2007, 53% (95% confidence interval, 44%-61%) of residents reported that they were initially trained in central venous catheterization using ultrasound guidance compared to 96% (95% confidence interval, 92%-99%) in 2013 (P < .0001). In 2007, more residents thought that faculty were insufficiently adopting ultrasound (42% versus 9%), and there was a lack of ultrasound teaching during residency training (14% versus 5%) compared to 2013.

CONCLUSIONS

The use of self-reported ultrasound guidance for central venous catheterization significantly increased from 2007 to 2013 at academic institutions. Most residents were aware of the benefits of using ultrasound guidance. Although faculty adoption of ultrasound for central venous catheterization remains a barrier, it has decreased.

Emergency Department Central Line-associated Bloodstream Infections (CLABSI) Incidence in the Era of Prevention Practices

OBJECTIVES

The incidence of central line-associated bloodstream infections (CLABSI) attributed to central venous catheters (CVCs) inserted in the emergency department (ED) is not widely reported. The goal was to report the incidence of ED CLABSI. Secondary goals included determining the effect of a CVC bundle introduced by the hospital infection prevention department to decrease CLABSI during the surveillance period.

METHODS

This was a prospective observational study over a 28-month period at an academic tertiary care center. A standardized electronic CVC procedure note identified CVC insertions in the ED. Abstractors reviewed inpatient records to determine ED CVC catheter-days. An infection prevention specialist identified CLABSIs originating in the ED using National Hospital Safety Network definitions from blood culture results collected up to 2 days after ED CVC removal. During the period of surveillance, a hospital-wide CVC insertion bundle was introduced to standardize insertion practices and prevent CLABSIs. Institutional CLABSI rates were determined by infection prevention from routine surveillance data.

RESULTS

Over the 28-month study period, 98 emergency physicians inserted 994 CVCs in 940 patients. The ED CVCs remained in place for more than 2 days in 679 patients, and the median number of days an ED CVC remained in use during the hospital stay was 3 (interquartile range = 2 to 7 days). There were 4,504 ED catheter-days and nine CLABSIs attributed to ED CVCs. The ED CLABSI rate was 2.0/1,000 catheter-days (95% confidence interval [CI] = 1.0 to 3.8). The concurrent institutional intensive care unit (ICU) CLABSI rate was 2.3/1,000 catheter-days (95% CI = 1.9 to 2.7). The ED CLABSI rate prebundle was 3.0/1,000 catheter-days and postbundle was 0.5/1,000 catheter-days (p = 0.038).

CONCLUSIONS

The CLABSI rates in this academic medical center ED were in the range of those reported by the ICU. The effect of ED CLABSI prevention practices requires further research dedicated to surveying ED CLABSI rates.

Sports medicine ultrasound (US) beyond the musculoskeletal system: use in the abdomen, solid organs, lung, heart and eye

The use of point-of-care ultrasound (US) by non-radiologists is not new and the expansion into sports medicine practice is relatively young. US has been used extensively to evaluate the musculoskeletal system including the diagnosis of muscle, tendon and bone injuries. However, as sports medicine practitioners we are responsible for the care of the entire athlete. There are many other non-musculoskeletal applications of US in the evaluation and treatment of the athlete. This paper highlights the use of US in the athlete to diagnose pulmonary, cardiac, solid organ, intra-abdominal and eye injuries.

Rates and timing of central venous cannulation among patients with sepsis and respiratory arrest admitted by the emergency department*

OBJECTIVES

Clinical guidelines for the acute management of emergency department patients with severe sepsis encourage the placement of central venous catheters. Data examining the timing of central venous catheter insertion among critically ill patients admitted from the emergency department are limited. We examined the hypothesis that prompt central venous catheter insertion during hospitalization among patients admitted from the emergency department acts as a surrogate marker for early aggressive care in the management of critically ill patients.

DESIGN

Retrospective cross-sectional analysis of emergency department visits using 2003-2006 discharge data from California, State Inpatient Databases, Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality.

SETTING

General medical or general surgical hospitals (n = 310).

PATIENTS

Patient hospitalizations beginning in the emergency department with the two most common diagnoses associated with central venous catheter (sepsis and respiratory arrest).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We identified the occurrence and timing of central venous catheter using International Classification of Diseases, 9th Revision, Clinical Modifications procedure codes. The primary outcomes measured were annual central venous catheters per 1,000 hospitalizations that began in the emergency department occurring emergently (procedure day 0), urgently (procedure day 1-2), or late (procedure day 3 or later). A total of 129,288 hospital discharges had evidence of central venous catheter. In 2003, 5,759 central venous catheters were placed emergently compared with 10,469 in 2006. The rate of emergent central venous catheter/1,000 increased annually from 228 in 2003, 239 in 2004, 257 in 2005, up to 269 in 2006. Urgent and late central venous catheter rates trended down (p < 0.001). In a multilevel model, the odds of undergoing emergent central venous catheter relative to 2003 increased annually: 1.08 (95% CI, 1.03-1.12) in 2004, 1.19 (95% CI, 1.14-1.23) in 2005, and 1.28 (95% CI, 1.23-1.33) in 2006.

CONCLUSIONS

Central venous catheters are inserted earlier and more frequently among critically ill patients admitted from the emergency department. Earlier central venous catheter insertion may require systematic changes to meet increasing utilization and enhanced mechanisms to measure central venous catheter outcomes.

CORD-AEUS: consensus document for the emergency ultrasound milestone project

In 2012, the Accreditation Council for Graduate Medical Education (ACGME) designated ultrasound (US) as one of 23 milestone competencies for emergency medicine (EM) residency graduates. With increasing scrutiny of medical educational programs and their effect on patient safety and health care delivery, it is imperative to ensure that US training and competency assessment is standardized. In 2011, a multiorganizational committee composed of representatives from the Council of Emergency Medicine Residency Directors (CORD), the Academy of Emergency Ultrasound of the Society for Academic Emergency Medicine (SAEM), the Ultrasound Section of the American College of Emergency Physicians (ACEM), and the Emergency Medicine Residents' Association was formed to suggest standards for resident emergency ultrasound (EUS) competency assessment and to write a document that addresses the ACGME milestones. This article contains a historical perspective on resident training in EUS and a table of core skills deemed to be a minimum standard for the graduating EM resident. A survey summary of focused EUS education in EM residencies is described, as well as a suggestion for structuring education in residency. Finally, adjuncts to a quantitative measurement of resident competency for EUS are offered.

Feasibility of percutaneous vagus nerve stimulation for the treatment of acute asthma exacerbations

OBJECTIVES

This study assessed the feasibility of an investigational vagus nerve stimulation (VNS) device for treating acute asthma exacerbations in patients not responding to at least 1 hour of initial standard care therapy.

METHODS

This was a prospective, nonrandomized study of patients treated in the ED for moderate to severe acute asthma (forced expiratory volume in 1 second [FEV(1)] 25% to 70% of predicted). Treatment entailed percutaneous placement of an electrode near the right carotid sheath and 60 minutes of VNS and continued standard care. VNS voltage was adjusted to perceived improvement, muscle twitching, or adverse events (AEs). All AEs, vital signs, FEV(1), perceived work of breathing (WOB), and final disposition were recorded.

RESULTS

Twenty-five subjects were enrolled. There were no serious AEs and no significant changes in vital signs. No subject required terminating VNS. One patient had minor bleeding from the procedure, and one had a hematoma and withdrew prior to VNS. AEs related to VNS were temporary and included cough (1 of 24), swallowing difficulty (2 of 24), voice change (2 of 24), and muscle twitching (14 of 24). These resolved when VNS ended. The FEV(1) improved at 15 minutes (median = 15.8%, 95% confidence interval [CI] = 9.3% to 22.4%), 30 minutes (median = 21.3%, 95% CI = 8.1% to 36.5%), and 60 minutes (median = 27.5%, 95% CI = 11.3% to 43.5%). WOB improved at 15 minutes (median = 53.9%, 95% CI = 33.7% to 73.9%), 30 minutes (median = 69.1%, 95% CI = 56.4% to 81.8%), and 60 minutes (median = 81.0%, 95% CI = 68.5% to 93.5%).

CONCLUSIONS

Percutaneous VNS did not result in serious AEs and was associated with improvements in FEV(1) and perceived dyspnea. Percutaneous VNS appears to be feasible for use in the treatment of moderate to severe acute asthma in patients unresponsive to initial standard care treatment.

Emergency medicine ultrasonography in rural communities

INTRODUCTION

The Canadian Association of Emergency Physicians (CAEP) published a position statement in 2006 encouraging immediate access to emergency medicine ultrasonography (EMUS) 24 hours a day, 7 days a week. However, barriers to advanced imaging care still exist in many rural hospitals. Our study investigated the current availability of EMUS in rural communities and physicians' ability to use this technology.

METHODS

A literature review and interviews with rural physicians were conducted in the summer of 2010 to design a questionnaire focusing on EMUS. The survey was then sent electronically or via regular mail in November 2010 to all Ontario physicians self-identified as "rural." Descriptive statistics and the Fisher exact test were used to analyze the data.

RESULTS

A total of 207 rural physicians responded to the survey (response rate 28.6%). Of the respondents, 70.9% were male, median age was 49 years and median year of graduation was 1988. The respondents had been in practice for a median of 20 years and had been in their present community for a median of 15 years. More than two-thirds of physicians (69.5%) practised in communities with populations of less than 10 000. Nearly three-quarters (72.6%) worked in a rural emergency department (ED). Almost all (96.9%) reported having access to ultrasonography in the hospital. However, only 60.6% had access to ultrasonography in the ED. Less than half (44.4%) knew how to perform ultrasonography, with 77.3% citing lack of training. Of those using EMUS, 32.5% were using it at least once per shift. The most common reason to use EMUS was to rule out abdominal aortic aneurysm (58.3%). Most respondents (71.5%) agreed or strongly agreed that EMUS is a skill that all rural ED physicians should have.

CONCLUSION

Patients in many rural EDs do not have immediate access to EMUS, as advocated by CAEP. This gap in care needs to be addressed to ensure that all patients, no matter where they live, have access to this proven imaging modality.

Risk factors for acute adverse events during ultrasound-guided central venous cannulation in the emergency department

BACKGROUND

Ultrasound (US) greatly facilitates cannulation of the internal jugular vein. Despite the ability to visualize the needle and anatomy, adverse events still occur. The authors hypothesized that the technique has limitations among certain patients and clinical scenarios.

OBJECTIVES

The purpose of this study was to identify characteristics of adverse events surrounding US-guided central venous cannulation (CVC).

METHODS

The authors assembled a prospective observational cohort of emergency department (ED) patients undergoing consecutive internal jugular CVC with US. The primary outcome of interest was a composite of acute mechanical adverse events including hematoma, arterial cannulation, pneumothorax, and unsuccessful placement. Physicians performing the CVC recorded anatomical site, reason for insertion, and acute complications. The patients with catheters were followed until the catheters were removed based on radiographic evidence or hospital nursing records. ED charts and pharmacy records contributed variables of interest. A self-reported online survey provided physician experience information. Logistic regression was used to calculate the odds of an adverse outcome.

RESULTS

  Physicians attempted 289 CVCs on 282 patients. An adverse outcome occurred in 57 attempts (19.7%, 95% confidence interval [CI] = 15.5 to 24.7), the most common being 31 unsuccessful placements (11%, 95% CI = 7.7 to 14.8). Patients with a history of end-stage renal disease (odds ratio [OR] = 3.54, 95% CI = 1.59 to 7.89), and central lines placed by operators with intermediate experience (OR = 2.26, 95% CI = 1.19 to 4.32), were most likely to encounter adverse events. Previously cited predictors such as body mass index (BMI), coagulopathy, and pulmonary hyperinflation were not significant in our final model.

CONCLUSIONS

Acute adverse events occurred in approximately one-fifth of US-guided internal jugular central line attempts. The study identified both patient (history of end-stage renal disease) and physician (intermediate experience level) factors that are associated with acute adverse events.

A descriptive comparison of ultrasound-guided central venous cannulation of the internal jugular vein to landmark-based subclavian vein cannulation

OBJECTIVES

The safest site for central venous cannulation (CVC) remains debated. Many emergency physicians (EPs) advocate the ultrasound-guided internal jugular (USIJ) approach because of data supporting its efficiency. However, a number of physicians prefer, and are most comfortable with, the subclavian (SC) vein approach. The purpose of this study was to describe adverse event rates among operators using the USIJ approach, and the landmark SC vein approach without US.

METHODS

This was a prospective observational trial of patients undergoing CVC of the SC or internal jugular veins in the emergency department (ED). Physicians performing the procedures did not undergo standardized training in either technique. The primary outcome was a composite of adverse events defined as hematoma, arterial cannulation, pneumothorax, and failure to cannulate. Physicians recorded the anatomical site of cannulation, US assistance, indications, and acute complications. Variables of interest were collected from the pharmacy and ED record. Physician experience was based on a self-reported survey. The authors followed outcomes of central line insertion until device removal or patient discharge.

RESULTS

Physicians attempted 236 USIJ and 132 SC cannulations on 333 patients. The overall adverse event rate was 22% with failure to cannulate being the most common. Adverse events occurred in 19% of USIJ attempts, compared to 29% of non-US-guided SC attempts. Among highly experienced operators, CVCs placed at the SC site resulted in more adverse events than those performed using USIJ (relative risk [RR] = 1.89, 95% confidence interval [CI] = 1.05 to 3.39).

CONCLUSIONS

While limited by observational design, our results suggest that the USIJ technique may result in fewer adverse events compared to the landmark SC approach.

Ultrasound image quality comparison between an inexpensive handheld emergency department (ED) ultrasound machine and a large mobile ED ultrasound system

Questions have been raised regarding image quality (IQ) provided by portable ultrasound (US) machines.

OBJECTIVES

To determine if a difference exists between images obtained with a common portable US machine and those obtained with a more expensive, larger US machine when comparing typical views used by emergency physicians.

METHODS

The authors performed a cross-sectional, blinded comparison of images from similar sonographic windows obtained on healthy models using a SonoSite 180 Plus and a General Electric (GE) 400 US machine. Both machines were optimized by company representatives. Images obtained included typical abdominal and vascular applications using the abdominal and linear transducers on each machine. All images were printed on identical high-resolution printers and then digitized using a bitmap format at 300 dots-per-inch resolution (RES). Images were then cropped, masked, and placed into random order comparing each view per model by a commercial Web design company (loracs.com). Three credentialed emergency physician sonologists, blinded to machine type, rated each image pair for RES, detail (DET), and total IQ as previously defined in the literature using a ten-point Likert scale; 10 was the best rating for each category. Paired t-test, 95% confidence intervals (95% CIs), and interobserver correlation were calculated.

RESULTS

A total of 49 image pairs were evaluated. Mean GE 400 RES, DET, and IQ scores were 6.8, 6.8, and 6.6, respectively. Corresponding SonoSite means were 6.3, 6.3, and 6.0, respectively. The difference of 0.5 (95% CI = 0.13 to 1.1) for DET was not statistically significant (p = 0.06). The differences of 0.5 (95% CI = 0.1 to 1.1) and 0.6 (95% CI = 0.2 to 1.2) for RES and IQ were statistically significant, with p = 0.01 and 0.01. There was good interobserver agreement (kappa = 0.71; 95% CI = 0.67 to 0.78).

CONCLUSIONS

A statistically significant difference was seen between GE 400 and SonoSite in IQ and RES, but not DET.

Real-time B-mode ultrasound in the ED saves time in the diagnosis of deep vein thrombosis (DVT)

We hypothesize that EPs can decrease the time to disposition when performing examinations for deep venous thrombosis (DVT) compared with disposition times using imaging specialists (IS). We performed a prospective, single-blind observational study at an academic ED over the course of 1 year. Patients were enrolled based on study physician availability. EPs ordered the corroborative ultrasound, then performed their own examination. EPs recorded patient triage time, ED results, and disposition times for both EP and IS departments. One hundred fifty-six patients were enrolled. Thirty-four (22%) were diagnosed with a DVT. Mean time from triage to EP disposition was 95 minutes and mean time from triage to radiology disposition was 220 minutes. The difference of 125 minutes was statistically significant (P <.0001). EPs and ISs had excellent agreement (kappa = 0.9). Compression ultrasound performed by EPs resulted in a significant decreased time to disposition. Agreement with ISs was excellent.

Frequency of incomplete abdominal aorta visualization by emergency department bedside ultrasound

OBJECTIVES

To determine how often emergency physicians (EPs) scanning the abdominal aorta (AA) of nonfasted emergency department (ED) patients are able to visualize the entire AA.

METHODS

The authors performed a retrospective study of patients receiving ultrasound (US) by EPs to rule out abdominal aortic aneurysm (AAA) at a suburban Level I ED. For patients being evaluated for possible AAA, EPs evaluated the entire length of the AA with US in short axis, making standard proximal, middle, and distal measurements. AAA was defined as dilation of the AA to >3 cm. Video of each US and data sheets were evaluated by a hospital-credentialed sonologist for visualization of the AA. Any portions of the AA not visualized were noted. If one third or more of the length of the AA was not seen, the examination was considered inadequate, allowing for potentially missing an AAA. Statistical analysis included descriptive statistics.

RESULTS

Ultrasounds of 207 patients were completed. In 35 patients (17%), a portion of the AA less than one third its length was not seen. In 17 patients (8%), a significant portion of the AA (at least one third its length) could not be visualized and therefore could have potentially concealed an AAA. In four patients, the AA could not be seen at all. There were 29 AAAs discovered (14%), and none were missed.

CONCLUSIONS

Significant portions of AA (at least one third of its length) were not visualized on bedside US in 8% of nonfasted patients; this rate is higher than radiology studies of fasted patients receiving US for evaluation of their aortas.

Comparison of perceived and actual times spent by residents performing ultrasound examinations on patients

Emergency medicine (EM) ultrasonography (US) has become a part of residency education. More residents will be taking time during their shifts to perform bedside US examinations for educational purposes, thus further challenging time resources.

OBJECTIVES

The authors' hypothesis was that EM residents could accurately estimate the amount of time spent on an US examination of a patient, thus being able to determine when too much time is being taken away from other duties.

METHODS

The authors performed a prospective, single-blind observational study over a four-month period of EM residents at a large community hospital emergency department (ED) with an EM residency program. When a study physician was present, residents were observed and timed from plugging in the machine to turning it off. The residents, who were not aware of the study, were then asked how long the examination had taken. The true scan time, perceived scan time by the resident, and whether the department was busy or not were recorded on standardized quality assurance data sheets by the study physician. When all beds in the department were occupied, the ED was considered to be busy; otherwise, it was noted as not busy. Statistical analysis included descriptive statistics, paired Student's t-test to compare perceived and actual scan times, and correlation analysis to evaluate for any effect of how busy the ED was on accuracy of perceived times.

RESULTS

Ninety-three observations were made on 17 different residents. The mean perceived time of examinations was 8 min 12 sec (95% CI = 6:42 to 9:42); the mean actual time was 9 min 53 sec (95% CI = 8:29 to 11:18). The difference of 1 min 42 sec (95% CI = 0:37 to 2:47) yielded a p = 0.003. Residents underestimated the time spent on the scan 64 of 93 (69%) times. How busy the ED was did not affect accuracy.

CONCLUSIONS

In this study, residents underestimated the amount of time spent performing an ultrasound examination. The small difference between the actual and perceived scan times was statistically significant; the clinical significance of this time difference is not known.

Elevated intracranial pressure detected by bedside emergency ultrasonography of the optic nerve sheath

Patients with altered level of consciousness may be suffering from elevated intracranial pressure (EICP) from a variety of causes. A rapid, portable, and noninvasive means of detecting EICP is desirable when conventional imaging methods are unavailable.

OBJECTIVES

The hypothesis of this study was that ultrasound (US) measurement of the optic nerve sheath diameter (ONSD) could accurately predict the presence of EICP.

METHODS

The authors performed a prospective, blinded observational study on emergency department (ED) patients with a suspicion of EICP due to possible focal intracranial pathology. The study was conducted at a large community ED with an emergency medicine residency program and took place over a six-month period. Patients suspected of having EICP by an ED attending were enrolled when study physicians were available. Unstable patients were excluded. ONSD was measured 3 mm behind the globe using a 10-MHz linear probe on the closed eyelids of supine patients, bilaterally. Based on prior literature, an ONSD above 5 mm on ultrasound was considered abnormal. Computed tomography (CT) findings defined as indicative of EICP were the presence of mass effect with a midline shift 3 mm or more, a collapsed third ventricle, hydrocephalus, the effacement of sulci with evidence of significant edema, and abnormal mesencephalic cisterns. For each patient, the average of the two ONSD measurements was calculated and his or her head CT scans were evaluated for signs of EICP. Student's t-test was used to compare ONSDs in the normal and EICP groups. Sensitivity, specificity, and positive and negative predictive values were calculated.

RESULTS

Thirty-five patients were enrolled; 14 had CT results consistent with EICP. All cases of CT-determined EICP were correctly predicted by ONSD over 5 mm on US. One patient with ONSD of 5.7 mm in one eye and 3.7 mm in the other on US had a mass abutting the ipsilateral optic nerve; no shift was seen on CT. He was placed in the EICP category on his data collection sheet. The mean ONSD for the 14 patients with CT evidence of EICP was 6.27 mm (95% CI = 5.6 to 6.89); the mean ONSD for the others was 4.42 mm (95% CI = 4.15 to 4.72). The difference of 1.85 mm (95% CI = 1.23 to 2.39 mm) yielded a p = 0.001. The sensitivity and specificity for ONSD, when compared with CT results, were 100% and 95%, respectively. The positive and negative predictive values were 93% and 100%, respectively.

CONCLUSIONS

Despite small numbers and selection bias, this study suggests that bedside ED US may be useful in the diagnosis of EICP.

Ultrasound-guided drainage of peritonsillar abscess by the emergency physician

The diagnosis of peritonsillar abscess (PTA) poses a challenge to emergency physicians (EPs). The decision to perform an invasive procedure with potential complications is based on clinical judgment that is often inaccurate. Although there is some mention of intraoral ultrasound in otolaryngology practice, there is none in the emergency medicine (EM) literature. However, this bedside emergency application of ultrasonography has the potential to be of considerable use in EM practice, and could allow EPs who previously deferred blind needle aspiration of a potential abscess to perform the procedure themselves. We report the cases of 6 patients who presented with probable PTA and were evaluated with intraoral ultrasound at the bedside by an EP. All 6 patients then underwent needle aspiration. As diagnosed on ultrasound, 3 of the patients had negative aspirations and were diagnosed with peritonsillar cellulitis. Three others were found to have PTA, with 2 requiring real-time ultrasound needle guidance to accomplish abscess drainage after multiple failures with the blind approach.

A study of bedside ocular ultrasonography in the emergency department

The use of ocular ultrasonography for the evaluation of emergency patients has recently been described in the emergency medicine (EM) literature. There are a number of potential uses that may greatly aid the emergency physician (EP) and avoid lengthy consultation or other diagnostic tests.

OBJECTIVE

To examine the accuracy of bedside ultrasonography as performed by EPs for the evaluation of ocular pathology.

METHODS

This prospective, observational study took place in a high-volume, suburban community hospital with an EM residency program. All patients arriving with a history of eye trauma or acute change in vision were eligible to participate in the study. A 10-MHz linear-array transducer was used for imaging. All imaging was performed through a closed eyelid, using water-soluble ultrasound gel. Investigators filled out standardized data sheets and all examinations were taped for review. All ultrasound examinations were followed by orbital computed tomography or complete ophthalmologic evaluation from the ophthalmology service. Statistical analysis included sensitivity, specificity, and positive and negative predictive values.

RESULTS

Sixty-one patients were enrolled in the study; 26 were found to have intraocular pathology on ultrasound. Of these, three had penetrating globe injuries, nine had retinal detachments, one had central retinal artery occlusion, and two had lens dislocations. The remaining pathology included vitreous hemorrhage and vitreous detachment. Emergency sonologists were in agreement with the criterion standard examination in 60 out of 61 cases.

CONCLUSIONS

Emergency bedside ultrasound is highly accurate for ruling out and diagnosing ocular pathology in patients presenting to the emergency department. Further, it accurately differentiates between pathology that needs immediate ophthalmologic consultation and that which can be followed up on an outpatient basis.

Significant hemoperitoneum in blunt trauma victims with normal vital signs and clinical examination

Clinical examination of the abdomen is generally reliable in stable trauma patients with no distracting or head injury. Patients involved in relatively minor trauma with normal examinations can be safely sent home in most instances. We report 6 cases of blunt abdominal trauma that had completely normal clinical examinations and vital signs but were found to have significant hemoperitoneum on trauma ultrasound examination. Four of the patients were examined for educational purposes just before planned discharge from the emergency department. These cases suggest that a screening ultrasound examination may have a role in the evaluation of most blunt trauma patients.

Intraperitoneal blood missed on a FAST examination using portable ultrasound

Bedside ultrasonography is rapidly gaining popularity in the evaluation of emergency patients. Several manufacturers have developed hand-held ultrasound machines that make the technology easy to transport and available in settings where such diagnostic tests were previously unobtainable. The miniaturization of equipment often means compromises and no studies exist comparing the high quality imaging capabilities of larger conventional ultrasound units to hand-held machines on actual patients. We present 3 cases in which intra-abdominal fluid stripes, important markers of intraperitoneal bleeding, were not visible with a popular hand-held unit, but were identified with a larger mobile ultrasound machine. These findings should caution emergency physicians to be aware of this limitation along with the many advantages of these new and popular hand-held ultrasound units.