BACKGROUND: The decision to terminate resuscitative measures in the setting of cardiac arrest is based on several criteria, some of which are subjective. Ultrasound in the emergency department has potentially added an objective data point to assist in this decision. OBJECTIVE: We sought to determine if emergency physicians who were trained in the use of ultrasound use it in cardiac arrest scenarios and if so, what effect they believe it has on the duration of the resuscitative event. Our hypothesis was that emergency physicians terminate resuscitative efforts sooner with visualization of cardiac standstill and feel more comfortable in doing so. METHODS: The ultrasound training program at Los Angeles County + University of Southern California Medical Center began in 1995. We surveyed all graduates of the residency program since that date about their use of ultrasound in cardiac arrest. RESULTS: Surveys were mailed to 154 practicing emergency physicians. One hundred and sixteen surveys (75%) surveys were returned. During residency, the majority of individuals (68%) reported that they had used ultrasound during at least 10 cardiac arrests. It was used to search for a reversible cause of cardiac arrest (pericardial effusion) or for documentation of cardiac standstill. Ninety-one percent of individuals used the ultrasound result as an aid in deciding when to terminate resuscitative efforts and 59% believed it shortened their resuscitation time. After graduation, only 53% of individuals in this study have ultrasound available in their daily clinical practice. For these individuals, 60% use it in more than 50% of their cardiac arrest situations. Ultrasound was used to shorten the code time (63%) as well as to reassure and confirm the presence of cardiac standstill for the physician (88%) and the resuscitation team (59%). CONCLUSION: Most emergency physicians in this cohort who have access to ultrasound use it in cardiac arrest cases and believe that it shortens code times.