Official Proceedings - AIUM

American Institute of Ultrasound in Medicine Proceedings J Ultrasound Med 32(suppl):S1–S134, 2013marks using ultrasound and shown examples of esophageal and trachealintubations. The cadavers were randomized to a tracheal or esophagealintubation, and the EM providers recorded their responses after performingdynamic transcricothyroid ultrasound (DTUS). Responses were timed,and the experience level of each provider with ultrasound was recorded.Results—The EM providers correctly identified the ET locationin 266 of 329 scans, for accuracy of 80.1% for all providers. The differencein accuracy between experienced and inexperienced providers wasnot statistically significant (P = .433), but more experienced providers hadshorter response times (P = .031). Physicians were not more accurate thanphysician assistants (P = .746), but physicians’ response times were shorter(P < .001).Conclusions—Our study suggests that EM providers withmore ultrasound experience, defined as >250 scans, are not necessarilymore accurate at identifying correct placement of ETs than those with lessexperience. Similarly, no statistically significant difference was seen inaccuracy between provider types. This study suggests that DTUS can beeasily learned by inexperienced sonographers, but given the relatively lowaccuracy rate of DTUS in this study, regardless of experience, DTUSshould be used only as an adjunct to current ET confirmation methods.1541012 Effect of the Prone Maximal Restraint (aka “Hog Tie”)Position on Cardiac Output and Other HemodynamicMeasurementsDavut Savaser,* Colleen Campbell, Ted Chan, Virag Shah,Chris Sloane, Allan Hansen, Eddie Castillo, Gary VilkeEmergency Medicine, University of California San Diego, SanDiego, California USAObjectives—To measure the impact of prone maximal restraint(PMR) with and without weight force on measures of cardiac function,including vital signs, oxygenation, stroke volume (SV), cardiac output(CO), and left ventricular outflow tract diameter (LVOTD).Methods—We conducted a randomized prospective crossoverstudy of healthy volunteers (18–60 years of age) placed in 5 different bodypositions: supine, prone, PMR, PMR with 50 lb added to the subject’sback (PMR50), and PMR with 100 lb added to the subject’s back(PMR100) for 3 minutes. Data were collected on subject vital signs andechocardiographic measurement of SV, CO, and LVOTD, measured bycredentialed emergency department faculty sonographers. Anthropomorphicmeasurements of height, weight, arm span, chest circumference, andbody mass index were also collected. Data were analyzed using repeatedmeasures analysis of variance to evaluate changes in each variable with respectivepositioning.Results—Twenty-five male subjects were enrolled in the study,ages ranging from 22 to 43 years. Cardiac output did change from thesupine to prone position, decreasing on average by 0.61 L/min (P = .013;95% confidence interval [CI], 0.142, 1.086 L/min). However, there was nosignificant change in CO when placing the patient in the PMR position(–0.11 L/min; P = .489; 95% CI, –0.43, 0.21 L/min), PMR50 position(0.19 L/min; P = .148; 95% CI, –0.07, 0.46 L/min), or the PMR100 position(0.14 L/min; P = .956; 95% CI, –0.29, 0.27 L/min) compared with theprone position. Systolic blood pressure never dropped below 100 mm Hgin any position; heart rate never increased above 100 beats per minute,and there were no incidents of syncope or other subjective complaints.Conclusions—CO is not significantly affected by the PMR positioncompared with the prone position, nor is it adversely affected withapplication of 50 or 100 lb of weight force to the back while in the PMRposition. The PMR position and a weight force of up to 100 lb does notcause hemodynamic compromise of the restrained patient.1541228 Ultrasound-Guided Peripheral Intravenous Insertion:Right Line at the Right TimeJames M. Joseph, Daniel Kagarise, Todd Henkaline, JamesWhite,* David Bahner Vascular Access, Ohio State UniversityMedical Center, Columbus, Ohio USAObjectives—To increase the success rate of initial intravenousline (IV) attempts using ultrasound guidance and to use expert assessmentand a triage process to choose the “right line at the right time.”Methods—We began in September 2005. Physician-initiatedrequests were placed in the electronic medical record and sent as consultsto the vascular access team. Ninety-eight insertions occurred between Septemberand December. The program has grown exponentially since its inceptionand to this date houses 47,153 requests for evaluation and insertionin a vascular access database. The vascular access team consists of 8 fulltimenurses covering approximately 850 beds. Additionally, we havetrained super users in 3 areas with varying degrees of success and datacollection.Results—The following data were queried from the vascularaccess database. Excluding the insertions completed by super users,requests for ultrasound-guided peripheral IV line insertion (USGPIV)totaled 47,153, 76.6% being attempted. Of the patients attempted, 32,366were successful on the first attempt. Subsequent attempts were successful92.4% of the time. The total success rate was 98.3%.Conclusions—USGPIV programs can be successful adjunctsto vascular access teams in serving patients with difficult access. Key conceptsfor branding success include using triage, assessment, ultrasoundguidance, and insertion by experienced vascular access nurses.Musculoskeletal and Interventional/IntraoperativeUltrasoundModerator: Humberto Rosas, MD1540764 Accuracy and Reliability of Direct Versus Indirect PeripheralNerve Cross-sectional AreaMark Shoreman, 1,2,3 * Jeffrey Strakowski, 1,2,3 Marcie Bockbrader,1,2 Mark Tornero, 1,2 Darin Bradshaw 1,2 1 PhysicalMedicine and Rehabilitation, Ohio State University, Columbus,Ohio USA; 2 Physical Medicine and Rehabilitation, RiversideMethodist Hospital, Columbus, Ohio USA; 3 MusculoskeletalDepartment, McConnell Spine, Sport, and Joint Center, Columbus,Ohio USAObjectives—Standardizing the sonographic examination is essentialto achieve diagnostic precision. Aspects of the examination, suchas the cross-sectional area (CSA) measurement technique, can be controlledand ultimately standardized. We sought to determine if direct peripheralnerve CSA measurement increases accuracy and reliability incomparison to the indirect method.Methods—Five novice sonographers and 3 healthy modelswere recruited. One expert sonographer led the novices through 3 peripheralnerve ultrasound training sessions in addition to a final “test-out” session.The expert then obtained 1 ideal transverse image of each model’sradial, median, ulnar, and sciatic nerves. Each sonographer (expert andnovice) then obtained 3 direct measurements of each nerve (3 models × 4nerves × 3 = 36) and 3 indirect measurements of each nerve (36 + 36 = 72measurements). The image order and method (direct/indirect) were randomizedprior to obtainment, and sonographers were blinded to their resultsas well as their colleagues’. The expert’s measurements representedthe accuracy gold standard. Accuracy was evaluated by calculating percentdeviation from expert (%DE). Inter-rater reliability was evaluated usingthe intraclass correlation coefficient (ICC). Variance measurements wereobtained using repeated measures analysis of variance (ANOVA).S21