Background: Emergency rooms prioritize rapid, life-saving interventions, often at the expense of patients’ psychosocial and existential needs. Patients in these settings are particularly vulnerable, yet such needs are frequently overlooked. Despite growing emphasis on person-centered care, knowledge of how existential needs (e.g. fear, anxiety, vulnerability) are expressed and addressed in emergency rooms remains limited. This study aims to describe how existential needs are expressed in the emergency room context. Methods: A qualitative secondary analysis was conducted using 108 field notes, 14 registered nurse interviews, and 15 patient interviews viewing emergency room care through a Fundamentals of Care framework lens. An inductive approach was inspired by key existential concepts described in a review and relevant to acute care. Reflexive thematic analysis was applied to each dataset, followed by cross-data comparison to identify patterns of existential needs. Results: The secondary analysis resulted in four themes; Existential vulnerability in a technical environment, Ensuring trust through presence and communication, Violations of privacy and dignity, and Moments of meaning-making through connection showing that existential needs in the emergency room are widespread and closely connected to both patients’ experiences and registered nurses’ care practices. Patients faced sudden transitions, fear, and emotional vulnerability, while registered nurses balanced these needs with organizational constraints. Existential concerns were expressed verbally and non-verbally and shaped by the environment, communication, and presence. Even brief, attentive encounters were experienced as meaningful and created a sense of safety in the stressful clinical setting. Conclusions: Addressing existential needs is integral to emergency care. Recognition and responsive care can mitigate patients’ emotional isolation and enhance safety, despite organizational constraints, highlighting the importance of integrating existential support with medical treatment. The organization should enable healthcare professionals to recognize and respond to existential needs as an integrated part of patient assessment and care interventions, supporting a more person-centered and holistic care in acute environments. This study highlights the importance of addressing existential needs within the emergency room, for both patients and registered nurses. Organizational constraints and ethical tensions challenge person-centered fundamental care, while underscoring safety as a crucial condition for meaningful and compassionate encounters. The findings offer guidance for emergency care professionals on integrating existential and relational awareness into practice, education, and policy. Trial registration: Clinical trial number: Not applicable.