Emergency Physician-performed Transesophageal Echocardiography in Simulated Cardiac Arrest
Abstract
Introduction: Transesophageal echocardiography (TEE) is a well-established method of evaluatingcardiac pathology. It has many advantages over transthoracic echocardiography (TTE), including theability to image the heart during active cardiopulmonary resuscitation. This prospective simulation studyaims to evaluate the ability of emergency medicine (EM) residents to learn TEE image acquisitiontechniques and demonstrate those techniques to identify common pathologic causes of cardiac arrest.
Methods: This was a prospective educational cohort study with 40 EM residents from two participatingacademic medical centers who underwent an educational model and testing protocol. All participantswere tested across six cases, including two normals, pericardial tamponade, acute myocardial infarction(MI), ventricular fibrillation (VF), and asystole presented in random order. Primary endpoints were correctidentification of the cardiac pathology, if any, and time to sonographic diagnosis. Calculated endpointsincluded sensitivity, specificity, and positive and negative predictive values for emergency physician (EP)-performed TEE. We calculated a kappa statistic to determine the degree of inter-rater reliability.
Results: Forty EM residents completed both the educational module and testing protocol. This resultedin a total of 80 normal TEE studies and 160 pathologic TEE studies. Our calculations for the abilityto diagnose life-threatening cardiac pathology by EPs in a high-fidelity TEE simulation resulted in asensitivity of 98%, specificity of 99%, positive likelihood ratio of 78.0, and negative likelihood ratio of0.025. The average time to diagnose each objective structured clinical examination case was as follows:normal A in 35 seconds, normal B in 31 seconds, asystole in 13 seconds, tamponade in 14 seconds,acute MI in 22 seconds, and VF in 12 seconds. Inter-rater reliability between participants was extremelyhigh, resulting in a kappa coefficient across all cases of 0.95.
Conclusion: EM residents can rapidly perform TEE studies in a simulated cardiac arrest environmentwith a high degree of precision and accuracy. Performance of TEE studies on human patients in cardiacarrest is the next logical step to determine if our simulation data hold true in clinical practice. [West JEmerg Med. 2017;18(5)830-834.]