Emergency department ultrasound: impact on ED stay times

Effect of Emergency Physician-Performed Point-of-Care Ultrasound and Radiology Department-Performed Ultrasound Examinations on the Emergency Department Length of Stay Among Pregnant Women at Less Than 20 Weeks' Gestation

OBJECTIVES

We sought to confirm retrospective studies that measured an approximately 20% reduction in emergency department (ED) length of stay (LOS) in early-gestation pregnant women who receive emergency physician-performed point-of-care ultrasound (US) examinations rather than radiology department-performed US examinations for evaluation of intrauterine pregnancy (IUP).

METHODS

A randomized controlled clinical trial was performed at an urban academic safety net hospital and 2 Naval medical centers in the United States. The allocation was concealed before enrollment. Clinically stable adult pregnant women at less than 20 weeks' gestation who presented to the ED with abdominal pain or vaginal bleeding were randomized to receive a point-of-care or radiology US to assess for IUP. The primary outcome measure was the ED LOS.

RESULTS

A total of 224 patients (point-of-care US, n = 118; radiology US, n = 106) were included for the analysis. The ED LOS was 20 minutes shorter in the point-of-care US arm (95% confidence interval [CI], -54 to 7 minutes). Adjusting for variability due to the location, the ED LOS was calculated to be 31 minutes shorter (95% CI, -64 to 1 minute) than for patients in the radiology US arm. Excluding patients in the point-of-care US arm who crossed over to radiology US after an inconclusive point-of-care US examination, the ED LOS was 75 minutes shorter than in the radiology US arm (95% CI, -97 to -53 minutes).

CONCLUSIONS

Early-gestation pregnant ED patients requiring pelvic US were discharged earlier when point-of-care US was used rather than radiology US; however, this trial did not achieve our target of 30 minutes. Nevertheless, our data support the routine use of ED point-of-care US for IUP, saving the most time if a conclusive IUP is identified.

Physicians using ultrasound in Danish emergency departments are mostly summoned specialists

BACKGROUND

Emergency ultrasound is a relatively new diagnostic discipline. It is used as an extension of the clinical examination and is ideal in the setting of acute illness. The objective of this study was to investigate how many Emergency Departments (EDs) in Denmark have implemented emergency ultrasound. We also wanted to give an idea of how many and which physicians have adopted ultrasound as a diagnostic tool so far.

METHODS

The study was a cross-sectional, descriptive, multicenter survey that included all physician staffed EDs in Denmark. An Internet based questionnaire was distributed by e-mail to all heads of department. Those departments who responded that ultrasound was available in their department were included in the second part of the study where all physicians working in the ED were contacted and asked to complete a second questionnaire.

RESULTS

All 28 eligible EDs participated in the first part of the study (Response rate: 100 %). 25 EDs (89 %, 95 % CI: 85-93) had ultrasound equipment available. Questionnaires were distributed to 1,872 physicians in these departments and 561 responded (Response rate: 30 %, 95 % CI: 28-32). Overall 257 (46 %, 95 % CI: 42-50) were users of emergency ultrasound and 304 were non-users (54 %, 95 % CI: 50-58). The largest group with 146 respondents (25 %, 95 % CI: 21-29) were anaesthetists with merely consult duty in the ED. When looking exclusively on physicians with on-call duty in the ED, thus excluding anaesthetists, only 146 (35 %, 95 % CI: 30-40) were users of ultrasound while 269 (65 %, 95 % CI: 60-70) were non-users. There was a considerable difference regarding age, level of training, and medical specialty between users and non-users. Users were mainly anaesthetists and attending physicians from other departments. The majority of non-users were young physicians with on call duty in the ED.

CONCLUSIONS

We have found that although almost all Danish EDs have ultrasound equipment available, few physicians working in the ED seem to have adopted the tool. Emergency Ultrasound is mainly performed by specialists who are summoned to the ED in case of severe acute illness and not by those physicians who comprise the backbone of the ED around the clock.

Initial accuracy of bedside ultrasound performed by emergency physicians for multiple indications after a short training period

PURPOSES

Emergency physician-performed ultrasonography holds promise as a rapid and accurate method to diagnose multiple diseases in the emergency department (ED). Our objective was to assess the initial diagnostic accuracy (first 55 explorations) of emergency physician-performed ultrasonography for multiple categories of ultrasound use after a short training period.

BASIC PROCEDURES

This was a prospective observational study conducted at an urban ED from June 2010 to March 2011 in patients with suspected cholecystitis, hydronephrosis, deep vein thrombosis, and different cardiovascular problems. Five physicians had a 10-hour training session before enrolling patients. The test characteristics of bedside ultrasonography were determined with the final radiologist/cardiologist interpretation.

MAIN FINDINGS

A total of 275 ultrasonographic examinations were performed (78 abdominal explorations, 80 renal explorations, 76 2-point compression ultrasonographic examinations in patients with suspected deep vein thrombosis, and 41 echocardiograms in patients with different acute cardiovascular problems). Radiologists/cardiologists detected 28 cases of cholecystitis, 26 cases of deep vein thrombosis, 49 cases of hydronephrosis, and 15 cases of significant cardiovascular alterations. The overall diagnostic accuracy of ED ultrasonograms yielded a sensitivity, specificity, positive predictive value, and negative predictive value of 92.6% (95% confidence interval [CI], 90%-99%), 89% (95% CI, 84%-94%), 86.2 % (95% CI, 82%-93%), and 94.2% (95% CI, 92%-99%), respectively. Nineteen (6.9%) false-positive results and 6 false-negative results (2.1%) were obtained.

PRINCIPAL CONCLUSIONS

Emergency physicians in our institution attained reasonably high initial accuracy in the performance of ultrasonography for a variety of clinical problems after a 10-hour training period.

How long does it take to perform emergency ultrasound for the primary indications?

Purpose

Although emergency ultrasound (EU) is gaining popularity, EU is performed in a minority of emergency departments (EDs). The perception may exist that EU is too time-consuming. This study sought to determine the duration of EUs performed for the primary indications by staff emergency physicians (EPs).

Methods

A prospective, time–motion study was conducted on a convenience sample of EUs at the Sudbury Regional Hospital ED from June to August 2006. All EPs had Canadian EU certification. A research assistant timed EUs. Primary EU indications in Canada are: cardiac arrest evaluation, rule-out pericardial effusion, rule-out intraperitoneal free fluid in trauma, rule-out abdominal aortic aneurysm, and rule-in intrauterine pregnancy. Descriptive statistics are reported.

Results

Eleven EPs performed 66 EUs for the primary indications on 51 patients. The mean EU duration was 137.8 s (range 11–465; CI 123.0–162.6). There was no difference in the duration of EUs performed by the two most experienced EPs (n = 37; duration = 129.4; CI = 96.4–162.4) compared to the other EPs (n = 29; duration = 148.4; CI = 110.6–186.2). Although subgroups were small, positive (n = 8; duration = 199.4; CI = 97.4–301.4), negative (n = 49; duration = 123.3; CI = 97.9–148.7), and indeterminate (n = 9; duration = 161.6; CI = 91.5–231.7) EUs did not differ in duration. There is some suggestion of differences in duration between types of EU, although again the subgroups were small: cardiac (n = 21; duration = 90.3; CI = 62.6–118.0), abdominal (n = 22; duration = 157.1; CI = 111.9–202.3), aneurysm (n = 15; duration = 170.1; CI = 117.5–222.7), transabdominal pelvic (n = 5; duration = 89.8; CI = 40.3–139.1), transvaginal (n = 3; duration = 246.0; CI = 30.6–461.4).

Conclusion

When performed by staff EPs with EU certification, mean EU duration for the primary indications was brief regardless of EP’s experience, EU type, or results.

Bedside ultrasound in pediatric emergency medicine fellowship programs in the United States: little formal training

BACKGROUND

Bedside ultrasound (BUS) can provide critical information in a rapid and noninvasive manner to the emergency physician. It is widely used in emergency departments (ED) throughout the nation. Literature shows that BUS shortens patient stay and increases patient satisfaction. General emergency medicine (EM) residencies incorporate BUS training in their curricula. However, there are limited data about the training that pediatric emergency medicine (PEM) fellows receive.

OBJECTIVE

To determine the extent of training and use of BUS in PEM fellowship programs.

METHODS

A 29-question survey was mailed to all (57) PEM fellowship program directors in the spring of 2006.

RESULTS

The response rate was 81% (46/57). Fifty-seven percent (26/46) of the responding PEM fellowship program directors reported that their faculty used BUS in their departments. At 50% (23/46) of programs, fellows perform BUS studies. Sixty-five percent (30/46) of PEM fellowships reported that their fellows receive some BUS training, but only 15 of these programs included BUS training in the curriculum as a 2- to 4-week ultrasound rotation.Sixty-five percent (30/46) of PEM fellowship programs had access to an ultrasound machine, but only 28% (13/46) of programs had their own machine. The main reason not to own an ultrasound machine was a lack of ultrasound expertise in their department (67%, 22/33). Bedside ultrasound training was provided by general EM physicians in 57% (17/30) of programs. Eighty-seven percent of the directors agree that BUS training would benefit their practice.The 2 factors significantly associated with the likelihood of having formal BUS training were access to an ultrasound machine (87% vs 55% P=0.04) and presence of an adult ED with an EM residency at the program (80% vs 42% P=0.03). Pediatric emergency medicine fellowship programs at children's hospitals were significantly less likely to have formal training (33.3% vs 74.2%; P=0.01).

CONCLUSIONS

Despite literature supporting the benefits of BUS in the ED, many PEM fellowship programs do not incorporate BUS training for their PEM fellows. Most PEM fellows who receive training in BUS are instructed by physicians trained in EM, not PEM.

Ultrasonography in community emergency departments in the United States: access to ultrasonography performed by consultants and status of emergency physician-performed ultrasonography

STUDY OBJECTIVE

Nearly all emergency medicine residency programs provide some training in emergency physician-performed ultrasonography, but the extent of emergency physician-performed ultrasonography in community emergency departments (EDs) is not known. We seek to determine the state of ultrasonography in community EDs in terms of access to ultrasonography by other specialists and performance of ultrasonography by emergency physicians.

METHODS

A 6-page survey that addressed access to ultrasonography performed by other specialists and emergency physician-performed ultrasonography was designed and pilot tested. A list of all US ED directors was obtained from the American College of Emergency Physicians. Twelve hundred of 5264 EDs were randomly selected to receive the anonymous survey, with responses tracked by separate postcard. There were 3 mailings from Fall 2003 to Spring 2004.

RESULTS

Overall response rate was 61% (684/1130). Respondents who self-reported as being academic with emergency medicine residents were excluded from further analysis (n=35). A sensitivity analysis (reported in parentheses) was performed on the key outcome question to adjust for response bias. As reported by ED directors, ultrasonography was available in the ED for use by emergency physicians at all times in 19% of EDs (12% to 28%), with an additional 15% (9% to 21%) reporting a machine available for use by emergency physicians in some capacity and 66% (51% to 80%) reporting that there was no access to a machine for emergency physician use. ED directors reported being requested or required to limit ultrasonography orders performed by radiology in 41% of EDs, with less timely access to radiology-performed ultrasonography in off hours. Of EDs with emergency physician-performed ultrasonography, the most common applications were Focused Assessment with Sonography for Trauma (FAST) examination (85%), code situation (72%), and check for pericardial effusion (67%). Of physicians performing ultrasonography, 16% stated they were currently requesting reimbursement (billing). The primary reason cited for not implementing emergency physician-performed ultrasonography was lack of emergency physician training. For the statement "emergency medicine residents now starting residency should be trained to perform and interpret focused bedside ultrasonography," 84% of ED directors agreed, 14% were neutral, and less than 2% disagreed.

CONCLUSION

Community ED directors continue to report barriers to obtaining ultrasonography from consultants, especially in off hours. Nineteen percent of community ED directors report having a machine available for emergency physician use at all times; however, two thirds of EDs report no access to ultrasonography for emergency physician use. A majority of community ED directors support residency training in emergency physician-performed ultrasonography.

The association between operator confidence and accuracy of ultrasonography performed by novice emergency physicians

The variable accuracy of emergency department (ED) ultrasound described in the literature has limited its utility as the sole imaging modality in critical decision making. Although ultrasound accuracy is highly dependent upon the technical abilities of the operator and conditions unique to each patient, no previous study of ED ultrasound has included estimates of operator confidence. This prospective observational study explores the association between operator confidence and the accuracy of ED ultrasound. Ultrasound was not performed in our ED until a formal training module was instituted. Patients were enrolled prospectively for the first year following the training module if they underwent one of the following ultrasound studies: abdominal examination for intraperitoneal fluid, right upper quadrant examination for gallstones, renal examination for hydronephrosis, pelvic examination for intrauterine pregnancy, abdominal examination for aorta diameter > 3 cm, or cardiac examination for pericardial fluid. In addition, formal ultrasound, computed tomography, magnetic resonance imaging, or an invasive procedure was required as a "gold standard" for each patient. Operators recorded their interpretation of the ED ultrasound and rated their confidence with the analysis before the formal imaging study or procedure. Test performance characteristics for each examination type and for all studies together were determined. The association between operator confidence and accuracy was explored using logistic regression and by determining test performance characteristics with patients stratified by confidence value. A total of 276 ED ultrasound studies were included. There were no significant differences in accuracy between ED attendings and residents. Overall accuracy, sensitivity, specificity, LR+, and LR- were 90%, 92%, 86%, 6.8, and 0.09, respectively. With confidence scores of 9 or 10 (n = 113), these values improved to 96%, 99%, 90%, 9.6, and 0.01, respectively. Logistic regression revealed an association between confidence and ED ultrasound accuracy (p < 0.001). It is concluded that a significant association exists between operator confidence and the accuracy of ED ultrasound. High confidence values are associated with clinically useful test performance characteristics.

Comparison of quality and cost-effectiveness in the evaluation of symptomatic cholelithiasis with different approaches to ultrasound availability in the ED

Ultrasound is the imaging study of choice for the detection of gallstones, but ultrasound through medical imaging departments (MI Sono) is not readily available on an immediate basis in many emergency departments (EDs). Several studies have shown that emergency physicians can perform ultrasound themselves (ED Sono) to rule out gallstones with acceptable accuracy after relatively brief training periods, but there have been no studies to date specifically addressing the effect of ED Sono of the gallbladder on quality and cost-effectiveness in the ED. In this study, we investigated measures of quality and cost-effectiveness in evaluating patients with suspected symptomatic cholelithiasis during three different years with distinctly different approaches to ultrasound availability. The study retrospectively identified a total of 418 patients who were admitted for cholecystectomy or for a complication of cholelithiasis within 6 months of an ED visit for possible biliary colic. The percentage of patients who had gallstones documented at the first ED visit improved from 28% in 1993, when there was limited availability of ultrasound through the Medical Imaging Department (MI Sono), to 56% in 1995, when MI Sono was readily available, to 70% in 1997, when both MI Sono and ED Sono were readily available (P <.001). There were also significant differences over the 3 years in the mean number of days from the first ED visit to documentation of gallstones (19.7 in 1993, 10.7 in 1995, 7.4 in 1997, P <.001); the mean number of return visits for possible biliary colic before documentation of gallstones (1.67 in 1993, 1.24 in 1995, and 1.25 in 1997, P <.001); and the incidence of complications of cholelithiasis in the interval between the first ED visit for possible biliary colic and the date of documentation of cholelithiasis (6.8% in 1993, 5.9% in 1995, 1.5% in 1997, P =.049). The number of MI Sonos ordered by emergency physicians per case of symptomatic cholelithiasis identified increased from 1.7 in 1993 to 2.5 in 1995 and dropped back to 1.7 in 1997, when 4.2 ED Sonos per study case were also done. The cost of ED Sonos was more than offset by savings in avoiding calling in ultrasound technicians after regular Medical Imaging Department hours. The indeterminate rate for ED Sonos was 18%. Excluding indeterminates, the sensitivity of ED Sono for detection of gallstones was 88.6% (95% CI 83.1-92.8%), the specificity 98.2% (95% CI 96.0-99.3%), and the accuracy 94.8% (95% CI 92.5-96.5%). We conclude that greater availability of MI Sono in the ED was associated with improved quality in the evaluation of patients with suspected symptomatic cholelithiasis but also with increased ultrasound costs. The availability of ED Sono in addition to readily available MI Sono was associated with further improved quality and decreased costs. The indeterminate rate for ED Sono was relatively high, but excluding indeterminates, the accuracy of ED Sono was comparable with published reports of MI Sono.