In numerous medical professions, the experience of medical emergencies, such as a sudden decline in vital parameters during surgical procedures, can precipitate a state of acute stress. Such stress can result in errors in the treatment of these emergencies. Furthermore, medical practitioners who frequently encounter these stressors, such as anesthesiologists, are at an elevated risk of developing health issues, including burnout. To reduce errors in the diagnosis and treatment of emergencies during surgery, an algorithm-based cognitive aid has been developed by adapting human factors concepts from aviation. The eGENA application was first released in 2020 and has since been implemented in numerous pilot hospitals in Germany. First results concerning user acceptance and the impact of eGENA on a range of performance indicators during surgical procedures have already been documented. This chapter presents an overview of the empirical results obtained thus far. Furthermore, the chapter presents new findings from a recent pilot study examining the impact of eGENA utilization on individual stress levels during surgical procedures. In a within-subjects experimental design, subjective stress measures were collected from 20 physicians and nurses during a simulated operation with and without eGENA. The results indicate an improvement in performance with eGENA, however, the influence of stress remains inconclusive. The theoretical and methodological aspects are discussed, and potential directions for further stress research in simulated surgical settings are proposed.