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Durch Fortschritte in der Technologie haben interventionelle Eingriffe am Herzen in den letzten Jahrzehnten einen herausragenden Stellenwert entwickelt und zu einer Reduktion von aufwendigen Operationen am Herzen geführt. Die Ausbildung im Herzkatheterlabor, die nach dem konservativen „appreticeship-model“ erfolgt, gerät in Anbetracht der sinkenden finanziellen Mittel, Zeitmangel und der ethischen Fragen bezüglich Patientensicherheit immer mehr in Diskussion. Die Entwicklung der Virtual-Reality-Simulatoren für Kathetereingriffe bietet hier durch die Realitätsnähe einen Ansatzpunkt für die Möglichkeit eines individuell angepassten, repetitiven Trainings ohne die Gefährdung eines Patienten. Standardsituationen als auch seltene Komplikationen können nachgestellt werden. Diese Studie weist nach, dass Training an den Virtual-Reality-Simulatoren CATHI und Immersion zu einer Risikoreduktioin bei der Durchführung einer perkutanen Coronarintervention führt. Zur Untersuchung der Effekte von Virtual-Reality-Training auf die Performance einer perkutanen Coronarintervention wurde an der medizinischen Klinik Wuerzburg eine kontrolliert-radnomisierte Studie mit 33 Anfängern in der interventionellen Kardiologie durchgeführt. 16 Teilnehmer (Simulationsgruppe) erhielten ein intensives acht-stuendiges Simulationstraining an zwei verschiedenen Virtual-Reality-Simulatoren (CATHI und Immersion), 17 Teilnehmer bildeten die Kontrollgruppe, die den konservativen Ausbildungsgang repräsentierte und kein Simulationstraining erhielt. Alle Teilnehmer mussten in Form einer Prä- und Postevaluation unter realitätsnahen Umständen im Herzkatheterlabor der Uniklinik Würzburg innerhalb von 30 Minuten eine perkutane Coronarintervention an einem pulsatilen Herzkreislaufmodell aus Silikon (CoroSim) eigenständig vornehmen. Dabei musste eine an einer Aufteilung lokalisierte hochgradige Stenose ohne Abgänge mit einer Länge von 10mm und einem Gefäßdurchmesser von 4mm eröffnet werden. Die Ergebnisse zeigten für die Präevaluation keine gruppenspezifischen Unterschiede. Nach dem Simulationstraining zeigte sich eine signifikante Verbesserung der Simulationsgruppe bei der Risikominimierung in Bezug auf Sicherheit bei der Anwendung des Führungskatheters, des Koronardrahts, des Ballon/Stents und bei der KM-Injektion, während sich die Kontrollgruppe in diesen Punkten nicht verbessern konnte. Die aktuelle Studie zeigt, dass Training an den Virtual-Reality-Simulatoren, als Ergänzung zur herkömmlichen Ausbildung, ein hohes Potential für die Optimierung von interventionellen Herzkathetereingriffen verfügt.
In 1999, a tragic catastrophe occurred in the Mont Blanc Tunnel, one of the most important transalpine road tunnels. Twenty-seven of the victims never left their vehicles as a result of which they were trapped in smoke and suffocated (Beard & Carvel, 2005). Immediate evacuation is crucial in tunnel fires, but still many tunnel users stay passive. During emergency situations people strongly influence each other’s behavior (e.g. Nilsson & Johansson, 2009a). So far, only few empirical experimental studies investigated the interaction of individuals during emergencies. Recent developments of advanced immersive virtual worlds, allow simulating emergency situations which makes analogue studies possible. In the present dissertation project, theoretical aspects of human behavior and SI in emergencies are addressed (Chapter 1). The question of Social Influence in emergency situations is investigated in five simulation studies during different relevant stages of the evacuation process from a simulated road tunnel fire (Chapter 2). In the last part, the results are discussed and criticized (Chapter 3). Using a virtual reality (VR) road tunnel scenario, study 1 (pilot study) and 2 investigated the effect of information about adequate behavior in tunnel emergencies as well as Social Influence (SI) on drivers’ behavior. Based on a classic study of Darley and Latané (1968) on bystander inhibition, the effect of passive bystanders on self-evacuation was analyzed. Sixty participants were confronted with an accident and smoke in a road tunnel. The presence of bystanders and information status was manipulated and consequently, participants were randomly assigned into four different groups. Informed participants read a brochure containing relevant information about safety behavior in emergency situations prior to the tunnel drives. In the bystander conditions, passive bystanders were situated in a car in front of the emergency situation. Participants who had received relevant information left the car more frequently than the other participants. Neither significant effect of bystanders nor interaction with information status on the participants’ behavior was observed. Study 3 (pilot study) examined a possible alternative explanation for weak SI in VR. Based on the Threshold Theory of Social Influence (Blascovich, 2002b) and the work of Guadagno et al. (2007), the perception of virtual humans as an avatar (a virtual representation of a real human being) or as an agent (a computer-controlled animated character) was manipulated. Subsequently, 32 participants experienced an accident similar to the one in study 1. However, they were co-drivers and a virtual agent (VA) was the driver. Participants reacted differently in avatar and agent condition. Consequently, the manipulation of the avatar condition was implemented in study 4. In study 4, SI within the vehicle was investigated, as drivers are mostly not alone in their car. In a tunnel scenario similar to the first study, 34 participants were confronted with an emergency situation either as drivers or co-drivers. In the driver group, participants drove themselves and a VA was sitting on the passenger seat. Correspondently, participants in the co-driver group were seated on the passenger seat and the VA drove the vehicle on a pre-recorded path. Like in study 1, the tunnel was blocked by an accident and smoke was coming from the accident in one drive. The VA initially stayed inactive after stopping the vehicle but started to evacuate after ca. 30 seconds. About one third of the sample left the vehicle during the situation. There were no significant differences between drivers and co-drivers regarding the frequency of leaving the vehicle. Co-drivers waited significantly longer than drivers before leaving the vehicle. Study 5 looked at the pre-movement and movement phase of the evacuation process. Forty participants were repeatedly confronted with an emergency situation in a virtual road tunnel filled with smoke. Four different experimental conditions systematically varied the presence and behavior of a VA. In all but one conditions a VA was present. Across all conditions at least 60% of the participants went to the emergency exit. If the VA went to the emergency exit, the ratio increased to 75%. If the VA went in the opposite direction of the exit, however, only 61% went there. If participants were confronted with a passive VA, they needed significantly longer until they started moving and reached the emergency exit. The main and most important finding across all studies is that SI is relevant for self-evacuation, but the degree of SI varies across the phases of evacuation and situation. In addition to the core findings, relevant theoretical and methodological questions regarding the general usefulness and limitations of VR as a research tool are discussed. Finally, a short summary and outlook on possible future studies is presented.