Research Forum Abstracts

64 Pain Does Not Prevent Returns to the Emergency

Definitive Imaging in Patients With Non-Specific Abdominal

DepartmentAaronson E, Borczuk P/Massachusetts General Hospital, Boston, MA

Study Objectives: Abdominal pain is the most common indication for computedtomography (CT) and ultrasonography (US) in the emergency department (ED), aswell as a common reason for patients to present to the ED. While the majority ofpatients that present to the ED with abdominal pain are definitively diagnosed, up to25% of these patients will ultimately be discharged with a diagnosis of non-specificabdominal pain. In the face of uncertainty, emergency physicians often order CT scansand US studies in the hopes of identifying an etiology of the abdominal complaints, orwith the belief that negative imaging will reassure both provider and patient andwill prevent future return. Our objective was to determine whether patients whoreceive imaging with no identifiable cause of their abdominal pain are less likely toreturn to the ED.

Methods: All patients with an ICD9 code that corresponded to non-specificabdominal pain (789.0-789.1) presenting to an urban academic ED from 7/2013-12/2013 were included in this study. Clinical and demographic data was collected andanalyzed. Chi squared analysis was used.

Results: There were 1,937 patients during the study period who were dischargedwith a non-specific GI diagnostic code. Of these patients, 49 (2.5%) returned within 72hours of treatment. There was no difference in the frequency of imaging in the group ofpatients that returned versus those that did not return (42.8% versus 37%; OR 1.27,95% CI .72-2.26). Return rate was not affected by the specific use of CT scanning (OR0.68, 95% CI 0.36 -1.3) or US (OR 1.16, 0.56-2.42) during their first visit.

Conclusion: Despite the common provider belief that knowledge of a negativestudy will reassure patients and ultimately prevent a return visit, to the contrary, thisstudy shows that imaging patients with non-specific abdominal pain does not preventreturn. Imaging should be reserved for answering specific clinical questions, and shouldnot be considered a means to preventing a return visit in patients with non-specificabdominal pain.

Comparison of Appendicitis Clinical Scoring Systems With

65 Physician-Determined Likelihood of AppendicitisRepplinger MD, Golden SK, Ebinger A, Svenson JE/University of Wisconsin School ofMedicine and Public Health, Madison, WI; University of Utah, Salt Lake City, UT

Background: Appendicitis is a common cause for abdominal pain in patientsseen in the emergency department. While computed tomography often helps in thediagnosis, it also exposes patients to ionizing radiation, which increases theirlifetime risk of cancer. In order to avoid this exposure, yet enhance the predictivepower of history and physical exam, various clinical scoring systems have beendeveloped.

Study Objectives: This study aims to compare the diagnostic accuracy of threeclinical scoring systems for the diagnosis of appendicitis: the Alvarado score, modifiedAlvarado score, and Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA) score.Physician-determined likelihood of appendicitis was also evaluated.

Methods: This is a HIPAA-compliant, IRB-approved prospective study of patientspresenting with abdominal pain to an academic emergency department with an annualcensus of 48,000. Patients were eligible for enrollment if they were over 11 years oldand had a computed tomography (CT) ordered to evaluate for appendicitis. For everyenrollee, all clinical parameters needed to calculate the clinical scores were recorded bythe assigned physician on a standardized data collection sheet prior to the patient goingto CT. The assigned physician was also asked to estimate the likelihood of appendicitis:<40%, 40-60%, 60-80%, or >80%. Clinical scores were considered positive if �7.5for the RIPASA Score and �7 for either the AS or MAS. The physician-determinedlikelihood of appendicitis was considered positive if >60%. We then calculatedsensitivity, specificity, positive predictive value (PPV), and negative predictive value(NPV) for each score, reported as point estimates with 95% confidence intervals, usingCT results as the reference standard. When CT results were equivocal, surgical findingsor clinical follow-up were used as the reference standard. Cohen’s unweighted kappavalues were also calculated for test pairs.

Results: We enrolled 236 patients from 2/2012-2/2014, including 142 (60.1%)women and 165 (69.9%) patients under age 40. The prevalence of appendicitis in thiscohort was 35.6%. The AS had a sensitivity of 0.52 (0.46-0.59), specificity 0.74 (0.69-0.80), PPV 0.53 (0.47-0.59), and NPV 0.74 (0.68-0.79). The MAS had a sensitivityof 0.38 (0.32-0.44), specificity 0.82 (0.77-0.87), PPV 0.53 (0.47-0.60), and NPV

S24 Annals of Emergency Medicine

0.70 (0.65-0.76). The RIPASA score had a sensitivity of 0.75 (0.69-0.81), specificity0.37 (0.31-0.43), PPV 0.40 (0.33-0.46), and NPV 0.73 (0.67-0.78). Physician-determined likelihood of appendicitis had a sensitivity of 0.64 (0.58-0.70), specificity0.72 (0.66-0.77), PPV 0.56 (0.49-0.62), and NPV of 0.78 (0.73-0.84). Kappa valueswere 0.77 (0.69-0.86) for AS versus MAS, 0.35 (0.26-0.44) for AS versus the RIPASAscore, 0.36 (0.24-0.48) for AS versus physician impression, 0.27 (0.20-0.35) for MASversus the RIPASA score, 0.27 (0.15-0.39) for MAS score versus physician impression,and 0.38 (0.28-0.48) for the RIPASA score versus physician impression.

Conclusion: None of the three clinical scoring systems were particularly sensitive orspecific for the diagnosis of appendicitis, nor did they agree with each other or thephysician’s impression. Further, physician clinical impression was as accurate as thescoring systems.

Comparison of Ultrasound and Plain Radiography for the

66 Detection of Long Bone FracturesBagan M, Bahl A, Brackney A, Joseph S/William Beaumont Hospital, Royal Oak, MI

Study Objective: To compare emergency department (ED) residents’ ability tocorrectly identify long bone fractures via two imaging modalities; ultrasound (US)versus plain radiography (X-ray).

Methods: This was an IRB-approved, randomized prospective study. Studysubjects included ED residents at a single site. Five types of fracture (transverse,comminuted, avulsion, oblique, buckle) were mechanically induced in 5 store-boughtchicken legs, and an additional 5 legs were left unfractured. Each of the chicken legswas then imaged by both US (short and long axis video clips) and X-ray(anteroposterior and lateral views). Subjects were randomized to either US or X-rayfirst, and additionally randomized to viewing order within each arm. Subjects receiveda 10-minute tutorial on identification of fractures by US and X-ray, and then weregiven 2 minutes to view each of the US and X-ray images. Subjects decided presence orabsence of fracture (primary endpoint). If a fracture was observed, subjects identifiedthe location and type of fracture (secondary endpoints). Mean proportions andstandard deviations (SD) were analyzed using paired T-test and linear models (SASversion 9.3, R software version 2.15.2). A P value of 0.05 was considered significant.

Results: A total of 40 residents (15 post-graduate year (PGY)-1, 12 PGY-2, 13 PGY-3) participated in the study. Thirty-one subjects were male and 19 were randomized to USfirst. Residents completed a mean of 185 (SD 95.8) US scans prior to the study (98 PGY-1, 205 PGY-2, 268 PGY-3). The primary endpoint of correctly identifying any fracturehad a higher mean proportion in the US arm than the X-ray arm, 0.89 (SD 0.11) and 0.75(SD 0.11) respectively. The secondary endpoint of fracture type was higher in the X-raythan US arm, with a mean proportion of 0.52 (SD 0.12) and 0.51 (SD 0.13) respectively.The secondary endpoint of fracture location was higher in the US than X-ray arm, with amean proportion of 1.00 (SD 0.03) and 0.97 (SD 0.09) respectively. Paired T-testscomparing the difference in proportions revealed a significant difference (P<.001) inthe primary endpoint (detection of fracture), by a difference in proportions of 0.145(0.0948-0.1952, 95% CI). There was no significant difference in proportions for thesecondary endpoints, including fracture type (P¼.5903) and fracture location (P¼.1173).While these were not significant, buckle and avulsion fractures were more commonlyidentified by US than Xray (mean proportion 0.78 versus 0.51, and 0.92 versus 0.55,respectively). Other fracture type were similar between US and X-ray (0.91 versus 0.95 fortransverse; 0.80 versus 0.76 for oblique; and 0.93 versus 0.92 for comminuted). A linearmodel using the difference in proportions of correct answers was performed using PGYlevel, number of prior scans (surrogate for experience), and to which arm subjects wererandomized, as covariates. PGY level (P<.0001) and number of previously completedscans (P<.0146) were statistically significant, but not to which arm subjects wererandomized (P<.5775).

Conclusion: This study shows that subjects were better able to identify fractures usingUS compared to X-ray, especially as level of US and ED experience increased. These resultsencourage the use of US for the assessment of isolated extremity injury, particularly whenthe injury is diaphyseal and the clinical suspicion for subtle fracture is high.

Emergency Medicine Residents Perspective on Ultrasound

67 TrainingKapoor M, Greenstein J, Davis M, Das D, Panebianco N/Staten Island UniversityHospital, Staten Island, NY; Cedars-Sinai Medical Center, Los Angeles, CA; Hospital ofUniversity of Pennsylvania, Philadelphia, PA

Study Objectives: In 2012, the Accreditation Council for Graduate MedicalEducation (ACGME) designated ultrasound (US) as one of the 23 milestones for EM

Volume 64, no. 4s : October 2014

Table 1. Predictors of adverse return visit within 30 days; Multivariate analysisof patients with diagnosis of renal colic (n¼148)

Covariates

Predictors of adversereturn visit within 30 days

OR (95% CI) P value

Sex (“Male” is reference) 1.72 (0.75, 3.94) .20Race (“White” is reference)Black 1.44 (0.57, 3.61) .80Hispanic 1.29 (0.50, 3.29) .93Other 1.67 (0.48, 5.81) .60

(“No” or “none” is reference)Age� 50 years 1.39 (0.58, 3.35) .46High risk (hx of renal colic,

recent urologic procedure, renalinsufficiency, single kidney,transplant, DM, HIV, or PCKD)

2.19 (1.07, 4.48) .03

Sign of infection(fever, HR�100, or WBC�11

0.45 (0.21, 0.97) .04

Creatinine�1.1 1.86 (0.76, 4.56) .04Not done or not documented 0.46 (0.14, 1.50) .07

Blood on urinalysis 0.77 (0.28, 2.14) .42Not done or not documented 1.22 (0.24, 6.24) .65

Nitrates or LE on urinalysis 0.85 (0.37, 1.97) .70Stone size � 5mm on CT scan 1.36 (0.57, 3.26) .65N/A, stone not detected 1.20 (0.30, 3.77) .96

Hydronephrosis by ED ultrasoundMild 1.62 (0.67, 3.90) .80Moderate or severe 2.13 (0.80, 5.63) .25

DM, Diabetes Mellitus; HIV, human immunodeficiency virus; PCKD, polycystic kidneydiease; LE, leukocyte esterase.

Research Forum Abstracts

graduates. In 2013, a multi-organizational committee composed of the Council ofEmergency Medicine Residency Directors (CORD), Society for Academic EmergencyMedicine (SAEM), and ACEP published a minimum standard of US skills required forgraduating emergency medicine residents. However, a national standard does not existamong emergency medicine residencies as to which US applications are taught, whatstandards residents are held to, and how residents perceive the quality of their training.Our objective was to determine the current status and extent of US teaching withinemergency medicine residency programs.

Methods: We performed a retrospective review of data obtained from a performanceimprovement project conducted by the Academy of Emergency Ultrasound, a section ofSAEM. An email link of a Web-based survey tool was sent to the UltrasoundCoordinators (if present) or toDepartmentDirectors of all ACGMEemergencymedicineresidency programs in the United States (n¼160). We requested that they forward thesurvey link to their residents. Additionally, at SAEM’s 2013 (Atlanta, GA) nationalconference, emergency medicine residents were given the survey in their welcome packetand were asked to place the responses in an anonymous collection box. The surveyconsisted of 23 questions regarding the extent and level of ultrasound exposure andcomfort of the resident in teaching and performing specific ultrasound applications.

Results: We obtained a total of 471 responses. Most residents were in their PGY 1year (34.6%), came from academic or urban settings (72.8%, 84.0% respectively), withhigh volumes (62.5% saw >90,000 patients per year). Most residents have a requiredUS rotation in their 1st year (70.9%). The majority had 4 dedicated weeks of UStraining (57.7%), while 10.45% had >4 weeks and 1.71% had just 1 week. Mostresidents have a formal ultrasound curriculum (98.0%) and lectures (97.0%); however,only 39.0% have a written US exam. Eighty-two percent of residents have USfellowship-trained faculty at their programs and 68.3% have US fellowship. A seniorUS elective is available at 78.4% of institutions and 31.7% of respondents plan ontaking the elective. In a minority of institutions (15.4%) the resident is required toorder a confirmatory study for the US exams they perform. When asked which USexams residents are most comfortable performing, the top five were: the FAST exam(99.1%), central venous access (96.3%), trans-abdominal pregnancy (86.6%), softtissue (86.1%) and peripheral venous access (84.6%). The five exams that residentswere least comfortable performing were: testicular torsion (84.4%), ovarian torsion(71.9%), ultrasound-guided nerve blocks (58.8%), trans-vaginal pregnancy (52.9%)and musculoskeletal (41.1%). In this survey, 26.9% were graduating residents. Ofthese graduating residents, 91.9% feel comfortable using US to make a diagnosticdecision and 89.5% feel comfortable teaching clinician performed ultrasoundapplications. When considering employment, 87.7% of senior-reported that nothaving US would influence their decision to work there.

Conclusion: There is variability in US teaching, resources, and resident comfortwith exams across residency programs. Senior emergency medicine residents arecomfortable using US to make diagnostic decisions and the availability of US mayaffect their employment decisions.

Bedside Ultrasound versus Computed Tomography in

68 Diagnosing Renal Colic and Predictors of 30-Day Return VisitsLeo M, Langlois B, Mitchell P, Pare J, Linden J, Amanti C, Nam C, Monrose E, Libby B,Carmody K/Boston Medical Center, Boston, MA; New York University, New York, NY

Study Objectives: Computed tomography (CT) scans are commonly used todiagnose renal colic. Due to the prevalence and frequent recurrence of renal colic, theroutine use of CT may increase health care costs and radiation exposure. Emergencyphysicians performed bedside ultrasound (US) may be a reliable alternative imagingmodality. The objectives of this study were to determine if differences exist betweenemergency physician performed US and CT in identifying presence of hydronephrosis;to describe test characteristics of US in the diagnosis of renal colic; and to identifypredictors of 30-day return visits in patients with renal colic.

Methods: This was a prospective observational study of emergency departmentpatients at an urban academic medical center from November 2010 to March 2014.Patients who presented with renal colic symptoms were screened for eligibility. Inclusioncriteria were: non-contrast CT of the abdomen and pelvis, English-speaking, age > 21,and able to provide contact information for follow-up. Research assistants obtainedconsent and emergency physician co-investigators trained in US, blinded to CT results,performed US, and recorded presence or absence of hydronephrosis. A 30-day medicalrecord review and follow-up phone call was completed to assess for return visits definedas: routine, intractable pain, urologic intervention, admission, or infection. We usedMcNemar’s test to compare bedside US and CT in the detection of hydronephrosis.Sensitivity, specificity, and positive and negative predictive values were calculated for US

Volume 64, no. 4s : October 2014

hydronephrosis in diagnosis of renal colic. Multivariate logistic regression was used toassess predictors of 30-day return visits. All data was analyzed using SAS 9.3.

Results: We enrolled 316 subjects, (14 were dropped and 17 were lost to 30-dayfollow-up). A total of 302 subjects were included in the primary analysis. US and CTwere not different in detecting hydronephrosis, 128 (42%) versus 118 (39%), P¼.14.US had high specificity (93%) and positive predictive value (93%) for the diagnosis ofrenal colic; sensitivity (68%), negative predictive value (68%). Predictors of 30-dayreturn visits related to renal colic are reported in Table 1. High risk patients, sign ofinfection, and creatinine > 1.1 were significantly associated with 30-day returns.

Conclusion: Emergency physician-performed bedside US and CT are similar indetection of hydronephrosis in patients with suspected renal colic. Our study suggeststhat US is a reliable first-line imaging modality for identifying renal colic. While otherclinical factors were predictors of 30-day return visits, stones > 5 mm on CT andhydronephrosis on US do not seem to be predictive.

Does a History of Difficult Venous Access Mean the Patient

69 Really Needs an Ultrasound-Guided IV?Fields JM, Renzi N, McCarter K, Paziana K/Thomas Jefferson University,Philadelphia, PA

Study Objectives: Intravenous (IV) access is the most frequent emergencydepartment (ED) procedure. Commonly, patients report a history of difficult venousaccess (DVA) or may not have visible or palpable veins on examination leading first-line ED providers to believe that traditional IV placement will fail and rescue vascularmethods such as ultrasound-guided (USG) or extrajugular (EJ) IVs are indicated. Thecurrent study set out to determine the effect of a history of DVA, venous visibility andvenous palpability on failure to establish an IV on the first attempt.

Methods: This was a prospective observational study in an urban academic EDwith an annual census of 45,000. Patients undergoing IV placement were consentedand enrolled. Trained research associates collected data on patient demographics andhistory. For the history of DVA patients were asked if they had any history of being a“tough stick” (defined as a history of requiring multiple attempts at IV placement) orhaving to undergo any of the following rescue vascular access techniques: USGIV, EJor central line (CL). Prior to any IV attempt, research associates asked the operatorplacing the IV if veins were visible (yes/no) and palpable (yes/no). The primary

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