Noise in the Intensive Care Unit: A Narrative Review of Its Characteristics, Clinical Impact, and Reduction Strategies

Aims Noise in the intensive care unit (ICU) is an environmental stressor affecting both patients and healthcare professionals. This narrative review synthesizes evidence from over 2 decades of research regarding ICU noise levels, sources, acoustic characteristics, and clinical impact. Design Narrative review. Data Sources A literature search was conducted in PubMed for studies published between January 2000 and July 2025. Search terms included combinations of ICU, intensive care, noise, sound levels, alarm fatigue, acoustic environment, delirium, sleep disruption, burnout, and hospital design. Reference lists of relevant reviews and original studies were screened. Review Methods Eligible publications included original research, simulation studies, systematic reviews, clinical guidelines, and qualitative reports focusing on adult ICUs. Only English‐language studies were included. Data were narratively synthesized to describe noise levels, sources, impacts, and mitigation strategies. Results Sound levels in most ICUs routinely exceed 55–60 dBA, with peak levels often surpassing 85–90 dBA—far above World Health Organization recommendations. Common noise sources include medical equipment alarms, staff activity, and environmental design features such as open layouts and reflective surfaces. Acoustic characteristics such as unpredictability and poor nighttime attenuation amplify stress. In patients, noise contributes to sleep fragmentation, circadian disruption, increased sedation needs, delirium, and adverse psychological outcomes. Among staff, excessive noise impairs communication, increases cognitive load, and contributes to fatigue and burnout. While various architectural, behavioral, and bundled interventions have shown promise, most demonstrate limited long‐term effectiveness. Conclusion Despite clear guidelines, ICU noise remains inadequately managed due to systemic barriers, including cultural norms, infrastructural constraints, and a lack of enforcement.