Stress by Alarms: Physiological and Psychological Stress Responses to Medical Alarms During an Immersive Virtual Intensive Care Environment

Both acute and chronic stress profoundly impact health and quality of life, with significant negative consequences for patients in Intensive Care Units (ICUs), including prolonged stays. Medical alarms are a major contributor to this stress, often being unfamiliar and frequent, leading to reduced health outcomes, discomfort and increased length of stay. From a human factors and engineering perspective, understanding this alarm-induced stress is crucial for designing safer, more patient-centered healthcare environments. This study investigated stress responses to medical alarms and associated cognitive demands. Thirty-one healthy young adults were immersed in a virtual ICU, assigned to three conditions: Current ICU - Alarm Engagement (alarms + interpretation task), Current ICU - Alarm Exposure (alarms only), or Silent ICU - No Alarms. Stress was measured using self-reported State-Anxiety (STAI) and objective Heart Rate Variability (HRV). Results show that the Alarm Engagement group reported significantly higher subjective stress (p <.05), demonstrating the impact of cognitive load from alarm interpretation. Conversely, the Silent ICU - No Alarms group consistently exhibited the lowest subjective stress, highlighting the psychological benefits of an alarm-free environment. While HRV did not show significant differences between alarm conditions (p >.05), an initial physiological arousal, likely a novelty effect, was observed. This discrepancy suggests perceived stress can be decoupled from immediate physiological responses. Our findings advocate for a holistic approach to stress measurement and emphasize the need for human factors and engineering solutions, like smart alarming, to reduce stress levels, cognitive burden, and foster a “Silent ICU” paradigm.