Two minutes after the physician(s)

had entered the simulator, a cardiac arrest occurred due to ventricular tachycardia displayed on the monitor. With the onset of the cardiac arrest, the “patient” closed his eyes, ceased to speak and to breathe, and pulses were no longer palpable. As our aim was to study the effects of team-building AMD3100 concentration during the early phase of a cardiac arrest, we ensured that Inhibitors,research,lifescience,medical all ad-hoc teams were complete ≤ 20 sec after the start of the cardiac arrest: in case the first physician of the “ad-hoc” group did not call for his colleagues within 15 sec they were immediately sent to the simulator. Regardless of any measures taken the patient stayed in cardiac arrest for 3 min. Thereafter, sinus rhythm could be achieved by defibrillation. To avoid a potentially traumatic experience the death of the “patient” was prevented by the nurse who, after six minutes, suggested appropriate measures. Upon completion of the scenario participants

were given a questionnaire and asked to rate on a 11-point Likert scale [16] the realism of the scenario, Inhibitors,research,lifescience,medical the realism of their own behaviour, and the realism of the behaviour of their colleagues (0 = “not at all realistic”, 5 = “somewhat realistic”, 10 = “very realistic”); the quality of their team’s performance (0 = “very low performance”, 5 = “average performance”, 10 = “very high performance”); Inhibitors,research,lifescience,medical the stress felt during simulation, and the stress felt during a real cardiac arrest (0 Inhibitors,research,lifescience,medical = “no stress at all felt”, 5 = “some stress felt”, 10 = “very high stress felt”). A video-assisted debriefing concluded the simulation. Data analysis Using frame-in-frame technology, the teams’ performance and the monitor displaying the “patient’s” vital signs were simultaneously recorded. Data were coded based on the video-tapes

recorded during simulation by two independent observers. Inter-observer agreement was assumed if the difference of timing of events was less than 5 sec. In this case, the shorter of two different timings was used for further analysis. Disagreements of more than five seconds in the timing of events were solved Inhibitors,research,lifescience,medical by jointly reviewing the videotapes. Hands-on time was defined as cardiac massage or defibrillation. Each defibrillation was rated as 10 sec of hands-on time. Interruptions of cardiac massage to allow for ventilation were rated as continuous cardiac massage if the interruption either was ≤ 10 sec. The first appropriate intervention was defined as first execution of either precordial thump, ventilation, cardiac massage, or defibrillation. Chest compression rates were calculated during the third minute after the onset of the cardiac arrest using a previously published formula [8]: compression rate = (compressions per 60-second segment) × 60/(60 – total pause time in the 60-second segment), where pause time indicates periods of time in which ≥ 2 seconds pass without chest compressions.