Use of Emergency Ultrasound in United States Pediatric Emergency Medicine Fellowship Programs in 2011

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1 ORIGINAL RESEARCH Use of Emergency Ultrasound in United States Pediatric Emergency Medicine Fellowship Programs in 2011 Jennifer R. Marin, MD, MSc, Noel S. Zuckerbraun, MD, MPH, Jeremy M. Kahn, MD, MSc Supplemental material online at Received February 17, 2012, from the Division of Emergency Medicine, Children s Hospital of Pittsburgh, Pittsburgh, Pennsylvania USA (J.R.M., N.S.Z.); Department of Pediatrics (J.R.M., N.S.Z.) and Clinical Research, Investigation, and Systems Modeling of Acute Illness Center, Department of Critical Care Medicine (J.M.K.), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania USA; and Department of Health Policy and Management, University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania USA (J.M.K.). Revision requested March 7, Revised manuscript accepted for publication March 8, This study was presented at the Pediatric Academic Societies Annual Meeting; April 2012; Boston, Massachusetts; and the Society for Academic Emergency Medicine Annual Meeting; May 2012; Chicago, Illinois. Address correspondence to Jennifer Marin, MD, MSc, Division of Emergency Medicine, Children s Hospital of Pittsburgh, 4401 Penn Ave, Administrative Office Building, Suite 2400, Pittsburgh, PA USA. jennifer.marin@chp.edu Abbreviations ED, emergency department; EM, emergency medicine; US, ultrasound Objectives The purpose of this study was to evaluate the use of and training in emergency ultrasound (US) in pediatric emergency departments (EDs) with pediatric emergency medicine (EM) fellowship programs. We hypothesized that emergency US use and pediatric EM fellow training have become widespread and that more structured training is being offered. Methods A survey instrument was sent via to all 69 United States pediatric EM fellowship directors or associate directors in the spring of We used descriptive summary statistics and χ 2 tests to determine characteristics associated with having a formal emergency US training program for pediatric EM fellows. Results The survey response rate was 87% (60 of 69). Among responding programs, 40 (67%) resided within a children s hospital (versus general ED). Fifty-one (85%) were designated level 1 pediatric trauma centers. Fifty-seven programs (95%) endorsed the use of emergency US in their EDs. Fifty-three (88%) provided at least some emergency US training to fellows, and 42 (70%) offered a structured emergency US rotation. Training has existed for a median of 3 years (interquartile range, 2 4 years). Twenty-eight programs (67%) with emergency US rotations provided fellow training in the both a general ED as well as a pediatric ED. There were no hospital or program level factors statistically associated with having a formal training program for pediatric EM fellows. Conclusions As of 2011, nearly all pediatric EDs with pediatric EM fellowship programs use emergency US. Pediatric EM fellowship programs provide emergency US training to their fellows, with a structured rotation being offered by most of these programs. Key Words emergency ultrasound; fellowship; pediatric emergency medicine; training The use of bedside emergency ultrasound (US) has dramatically increased in the last decade. According to data from 2002, more than 90% of general academic emergency departments (EDs) use emergency US. 1 The American College of Emergency Physicians has outlined training pathways for both residents and practicing physicians in the performance of emergency US examinations. 2 In addition, emergency US training has been a requirement of the Accreditation Council for Graduate Medical Education for emergency medicine (EM) residency programs since Adoption of routine emergency US use and training in pediatric EDs remain incomplete. According to a 2006 survey of pediatric EM fellowship programs, little more than half of institutions used emergency US in their practice, and only half of those 2012 by the American Institute of Ultrasound in Medicine J Ultrasound Med 2012; 31:

2 incorporated emergency US into pediatric EM fellowship training. 4 Data from a 2008 survey of children s hospitals EDs showed that only 60% were using emergency US for managing patients. 5 Emergency US use in pediatric EM since that time has not been assessed. The primary objective of our study was to describe the current state of emergency US in EDs with pediatric EM fellowship programs in 2011, hypothesizing that use has become more widespread in recent years. The secondary objective was to identify factors associated with a program having formal emergency US training for pediatric EM fellows. Materials and Methods Study Design and Population We conducted a cross-sectional study of pediatric EM fellowship programs using an online survey in June Program directors and coordinator s were obtained from the most current published list available (May 2011). 6 The Institutional Review Board at our institution reviewed and approved all study procedures. Survey Content and Administration We sought to measure 4 specific domains: details of the emergency US program, indications for emergency US use, training for pediatric EM fellows, and barriers to emergency US use. We developed the survey content based on a review of the existing literature on both adult and pediatric emergency US use and training. 1,4,7 10 Questions were structured for either categorical response types (in the case of program details and training) or Likert scale response types (in the case of indications and barriers to emergency US). For questions with categorical responses, we also provided an other category, in which case we solicited a freetext response. The initial survey draft was piloted among 4 pediatric EM fellowship directors in Canada and 14 EM US fellowship directors in the United States and revised for content and clarity based on their feedback. The final 32-question survey instrument (online Appendix) was sent via to all 69 pediatric EM fellowship program directors or associate directors using an on-line survey tool (SurveyMonkey, Palo Alto, CA). Program directors were invited to either complete the survey themselves or to forward the survey to a different individual in their division/department if they thought that individual would be more knowledgeable about emergency US at their institution. Pediatric EM fellowship administrative coordinators were also contacted and informed of the survey in an effort to raise visibility and improve response rates. A presurvey information was sent 3 days before the survey, and a follow-up reminder was sent 2, 4, and 6 weeks after the initial Survey responses were anonymous, and Internet protocol addresses were not stored in the survey results. To incentivize participation, individuals who completed the survey were given the option of being entered into a lottery for a $100 gift card. Data Analysis Survey data were exported into Stata 10.0 (StataCorp, College Station, TX) for statistical analysis. We excluded those surveys for which at least half of the survey was not completed. 12 Free-text other responses were either reclassified to one of the listed responses or analyzed as new responses. Analysis included descriptive summary statistics such as means, standard deviations, medians, and ranges. To evaluate temporal trends in emergency US use and training, basic summary statistics from our survey were qualitatively compared to the results of a previous survey. 4 χ 2 tests were used to determine the program characteristics associated with having a structured emergency US training program for fellows. For these analyses, P <.05 was considered significant. For questions involving Likert scales (almost always, most of the time, occasionally, rarely, or never; and strongly agree, agree, neutral, disagree, or strongly disagree), we combined responses into 3 meaningful groups (almost always/most of the time, occasionally/rarely, or never; strongly agree/agree, neutral, or disagree/strongly disagree) for ease of interpretation. Results Individuals from 62 of 69 programs responded to the survey. Two respondents did not complete most of the survey; therefore, a total of 60 surveys were included for analysis (87% effective response rate). Fifty-three respondents (88%) were pediatric EM fellowship directors or associate directors; 5 (8.3%) identified themselves as the emergency US director or equivalent; 1 (1.7%) was the medical director for the ED; and 1 (1.7%) was the pediatric EM fellowship coordinator. The characteristics of the responding programs are listed in Table 1. Most programs were associated with a children s hospital, were designated level 1 trauma centers, and served a moderate volume of ED patients. Twenty-six (43%) institutions reported having US services from the department of radiology available around the clock. Another 29 (48%) reported having these services available during the day and available on an oncall basis at night, with 3 of those programs indicating that US could only be provided for certain conditions overnight (eg, testicular torsion and intussusception) J Ultrasound Med 2012; 31:

3 Table 1. Institutional Characteristics (N = 60) Characteristic n (%) ED type Pediatric ED in a children s hospital 40 (66.7) Pediatric ED within a general ED 20 (33.3) ED annual patient volume <20,000 1 (1.7) 20,000 39, (31.7) 40,000 59, (23.3) 60,000 79, (25.0) 80, (18.3) Radiology US services available around the clock 26 (43) Number of 1st-y pediatric EM fellows 1 14 (23.3) 2 29 (48.3) 3 9 (15.0) 4 3 (5.0) 5 2 (3.3) Other a 3 (5.0) ED trauma level designation Level 1 51 (85.0) Level 2 1 (1.7) Level 3 1 (1.7) Unsure 1 (1.7) Not a designated trauma center 6 (10) ED indicates emergency department; EM, emergency medicine; and US, ultrasound. a One program did not accept any new first- year fellows for 2011; 1 respondent did not indicate the number of fellows; and 1 program accepts a fellow every 3 years. A comparison of emergency US use at responding institutions from our survey and a 2006 survey 4 is shown in Table 2. According to our results, 95% (57) of all programs reported at least some emergency US use at their institution, compared to 57% (26) in Of those EDs that use emergency US, 37 (65%) have access to 1 US machine, and 14 (25%) have access to 2 machines. Eighty-eight percent of pediatric EM fellowship programs provide at least some emergency US training to their fellows today, compared to 65% of programs in 2006, and 79% of these programs offer a structured emergency US rotation today. These emergency US rotations have existed for a median of 3 years (interquartile range, 2 4 years) and the mean duration of the emergency US rotation ± SD is 4.1 ± 2.0 weeks. Twenty-eight of the 42 programs (67%) with emergency US rotations provide fellow training in both a general ED as well as a pediatric ED. There were no specific hospital or program level factors associated with having a structured training program for pediatric EM fellows (Table 3). Figure 1 shows the methods used to train pediatric EM fellows in emergency US, and Figure 2 shows the different components integrated into emergency US rotations. Five institutions have a pediatric-specific 1-year emergency US fellowship available. The frequency of emergency US use for a given examination is shown in Tables 4 and 5. More than half of the programs use the focused assessment with sonography for trauma and soft tissue emergency US examinations almost always or most of the time for patients with trauma and those with skin and soft tissue infections, respectively. Forty percent of programs use emergency US for central venous access with similar frequency. Respondents were asked to rate their level of agreement with specific barriers to using emergency US as it applies to their division/department (Figure 3). The most frequently endorsed barrier was lack of sufficient time to learn emergency US. Lack of funds, need, and sufficient literature were rarely endorsed. Discussion Emergency US has become an integral part of the care of patients presenting to general acute care EDs and the training of general emergency physicians. 1,8,13 Our research shows that currently its use is accepted and has become widespread in the care of pediatric patients presenting to hospitals with a pediatric EM training program. Nearly all institutions surveyed reported use of emergency US. Table 2. Emergency Ultrasound Characteristics at Institutions in 2006 and 2011 Characteristic 2006, n (%) a 2011, n (%) Emergency US use 26/46 (57) 57/60 (95) Quality assurance process in place 13/26 (50) 35/57 (61) Performed by general EM physician 9/13 (69) 7/35 (20) Credentialing program in place for NA 32/57 (56) physicians Hospital privileging in emergency US NA 21/57 (37) Image storage Paper, stored by ED NA 4/57 (7) Paper, stored in medical record NA 5/57 (9) Electronic, stored by ED NA 24/57 (42) Electronic, available in medical record NA 6/57 (10) Other b NA 18/57 (32) Billing for emergency US services 0 (0) 8/57 (14) Emergency US training for pediatric EM fellows 30/46 (65) 53/60 (88) Emergency US rotation 15/30 (50) 42/53 (79) ED indicates emergency department; EM, emergency medicine; NA, not applicable; and US, ultrasound. a Data from Ramirez-Schrempp et al. 4 b Ten programs did not store images; 8 respondents were unsure how images were stored. J Ultrasound Med 2012; 31:

4 Table 3. Factors Associated With Structured Pediatric Emergency Medicine Fellowship Emergency Ultrasound Training Formal Emergency No Formal Emergency Factor US Training, % (n = 42) US Training, % (n = 18) P 24/7 radiology US available ED type Pediatric General ED volume <60, , Level 1 trauma center Annual number of 1st-y fellows ED indicates emergency department; and US, ultrasound. This finding is in contrast to data from 2006, when little more than half of programs reported use of emergency US and more than one-third did not have access to a US machine, 4 strengthening the evidence in support of a dramatic rise in emergency US use in EDs with pediatric EM training programs. In recent years, the pediatric emergency US community has made several strides in advancing current emergency US knowledge and practice. First, there has been a marked increase in the literature regarding the use of emergency US in pediatric patients in the last several years Second, there are now several specialized emergency US fellowship programs available to pediatric EMtrained individuals. Finally, consensus and policy statements have been published/revised regarding the use of US in the general emergency setting. 3,26,27 Pediatric EM physicians may adopt these statements as guides in the absence of pediatric-specific recommendations. We found no specific institutional factors statistically associated with a program s having formal emergency US training for pediatric EM fellows, likely because of the small number of programs without emergency US training and the resulting low power. The presence of aroundthe-clock US from the department of radiology did appear to trend toward statistical significance, with half of programs without formal emergency US training having radiology US available and only about one-fourth of those with formal training having these radiology services available. Many institutions do not have the resources to support US examinations performed by sonographers and interpreted by radiologists during off hours (constituting most hours of service of the ED) 28,29 ; therefore, these may be the settings where emergency US would be needed most. Figure 1. Methods of training in emergency ultrasound for pediatric emergency medicine (PEM) fellows. Note that programs may use more than 1 method. CME indicates continuing medical education. Figure 2. Components of emergency ultrasound rotations. Note that programs may have answered yes to more than 1 component. *Trainees engaged in teaching other learners J Ultrasound Med 2012; 31:

5 Table 4. Use of Emergency Ultrasound for Specific Diagnostic Indications (N = 57) Almost Always/ Occasionally/ Indication Most of the Time, n (%) Rarely, n (%) Never, n (%) Trauma evaluation (ie, FAST) 36 (63) 20 (35) 1 (2) Soft tissue evaluation (eg, abscess, foreign bodies) 30 (53) 23 (40) 4 (7) Cardiac arrest (ie, cardiac echocardiography) 21 (37) 33 (58) 3 (5) Evaluation of pregnancy 18 (32) 28 (49) 11 (19) Precatheterization bladder volume 6 (11) 44 (77) 7 (12) Surgical abdominal condition (eg, pyloric stenosis, intussusception, 5 (9) 23 (40) 21 (37) appendicitis) Dehydration/shock (ie, IVC assessment) 3 (5) 38 (67) 16 (28) Fracture evaluation 3 (5) 12 (21) 27 (47) Evaluation for hydronephrosis/nephrolithiasis (ie, renal US) 2 (4) 33 (58) 22 (39) Ocular trauma 0 (0) 26 (46) 31 (54) Elevated intracranial pressure (ie, optic nerve sheath diameter) 0 (0) 22 (39) 35 (61) FAST indicates focused assessment with sonography for trauma; IVC, inferior vena cava; and US, ultrasound. Table 5. Use of Emergency Ultrasound for Specific Procedural Indications (N = 57) Almost Always/ Occasionally/ Indication Most of the Time, n (%) Rarely, n (%) Never, n (%) Central venous access 23 (40) 25 (44) 9 (16) Incision and drainage 21 (37) 29 (51) 7 (12) Difficult peripheral venous access 15 (26) 34 (60) 8 (14) Nerve blocks 7 (12) 21 (37) 29 (51) Arthrocentesis 2 (4) 27 (47) 28 (49) Lumbar puncture 1 (2) 26 (46) 30 (53) Figure 3. Respondents who strongly agreed or agreed with each barrier to emergency ultrasound use. ED indicates emergency department; and PEM, pediatric emergency medicine. J Ultrasound Med 2012; 31:

6 Our study shows that trauma and skin and soft tissue infections remain the 2 most common indications for emergency US use in pediatric ED patients from the perspective of survey respondents. This finding was shown in 2 previous surveys 4,5 and is not surprising given that the focused assessment with sonography for trauma examination was the first 30 and perhaps most well-studied bedside US examination and that soft tissue infections represent an ever-growing indication for patients to seek emergency care 34 ; the soft tissue US examination is quick and relatively easy to learn, 22 and several studies have shown its utility Despite the widespread use reported in our survey, respondents still endorsed barriers to adoption of emergency US in their EDs. The most common factor was a lack of time available for learning this new skill. Indeed, to become adept at emergency US examinations, physicians need to build an appropriate amount of time and effort into their schedules. According to the American Institute of Ultrasound in Medicine, in the absence of training during residency or fellowship, acceptable US experience could be demonstrated by completing 100 American Medical Association Physician s Recognition Award category 1 credits dedicated to diagnostic US as well as performing and interpreting at least 300 US examinations within a 3-year period. 26 The American College of Emergency Physicians recommends initial training with a 16- to 24-hour introductory course that covers the core applications, most of which are relevant mostly in adult patients, or with 4- to 8-hour courses that cover single or a combination of applications and the completion of at least 25 examinations in each application. 11 Currently, there are few publications related to pediatric EM training in emergency US, 22 and it is not known what training is needed to establish competency. As of the last several years, pediatric EM physicians have begun using emergency US more and more; however, pediatric EM physicians still lag behind our general EM colleagues. According to data from 10 years ago, 92% of EM residency program directors reported emergency US use in their EDs; 51% had a credentialing/privileging plan in place; and 71% had a quality assurance program. 1 Reasons for these findings may be that most of the literature in emergency US is in adult patients, with emergency US being performed by EM physicians, and there is a lack of evidence-based training for pediatric EM physicians, which exists for general EM physicians. Furthermore, there are no published guidelines for training during pediatric residencies and pediatric EM fellowships. The use of emergency US has now become a part of the armamentarium of pediatric EM physicians; therefore, further work to develop appropriate training protocols and educational tools is needed to ensure safe, responsible, and consistent emergency US use in pediatric patients. Our study had some limitations. First, 9 of the 69 eligible programs did not respond to our survey; therefore, our data might not reflect the true state of emergency US use in pediatric EDs with pediatric EM fellowship programs currently. It is possible that those who responded to the survey were more likely to be at institutions that use emergency US currently; and that factor may have biased our results. However, the survey responses were anonymous; therefore, individuals should have been able to respond with candor. In addition, our high response rate makes any substantive differences in data interpretation unlikely. 38 Second, the survey was sent to pediatric EM fellowship directors, and in some cases they may not have been the most knowledgeable individuals regarding emergency US at their institutions. However, we did instruct directors to have other individuals complete the survey if they thought they were more appropriate. In conclusion, as of 2011, nearly all pediatric EDs with pediatric EM fellowship programs in the United States use emergency US. Pediatric EM fellowship programs are providing emergency US training to their fellows, with a structured rotation being offered by most of these programs. The next step is the development of standardized educational tools for training pediatric EM fellows. References 1. Moore CL, Gregg S, Lambert M. Performance, training, quality assurance, and reimbursement of emergency physician-performed ultrasonography at academic medical centers. 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