Which term refers to an event that has a powerful emotional impact on a rescuer, potentially causing an acute stress reaction?

The correct term that refers to an event with a powerful emotional impact on a rescuer, potentially causing an acute stress reaction, is a critical incident. A critical incident is typically an event that poses significant challenges to the emotional well-being of first responders or individuals involved in high-stress situations, such as traumatic injuries, fatalities, or any situation that exceeds a person's normal coping abilities. These events can lead to acute stress reactions, which may manifest as anxiety, irritability, or emotional distress.

In contrast, other terms in the options describe processes or concepts related to managing stress rather than defining the event itself. CISM (Crisis Intervention Stress Management) refers to a specific program designed to help individuals cope with the psychological aftermath of critical incidents. Demobilization entails returning individuals to a state of readiness after a critical incident, usually involving debriefing and assessment. Defusing is an immediate, informal discussion following a traumatic event to promote emotional wellbeing and assess the need for further intervention. While these terms relate to the aftermath and management of stress from critical incidents, the term that directly describes the impactful event itself is the critical incident.