Background: The intensive care environment in hospitals has been the subject of significant empirical and qualitative research in the 2005–2020 period. Particular attention has been devoted to the role of infection control, family engagement, staff performance, and the built environment ramifications of the recent COVID-19 global pandemic. A comprehensive review of this literature is reported summarizing recent advancements in this rapidly expanding body of knowledge. Purpose and Aim: This comprehensive review conceptually structures the recent medical intensive care literature to provide conceptual clarity and identify current priorities and future evidence-based research and design priorities. Method and Result: Each source reviewed was classified as one of the five types—opinion pieces/essays, cross-sectional empirical investigations, nonrandomized comparative investigations, randomized studies, and policy review essays—and into nine content categories: nature engagement and outdoor views; family accommodations; intensive care unit (ICU), neonatal ICU, and pediatric ICU spatial configuration and amenity; noise considerations; artificial and natural lighting; patient safety and infection control; portable critical care field hospitals and disaster mitigation facilities including COVID-19; ecological sustainability; and recent planning and design trends and prognostications. Conclusions: Among the findings embodied in the 135 literature sources reviewed, single-bed ICU rooms have increasingly become the norm; family engagement in the ICU experience has increased; acknowledgment of the therapeutic role of staff amenities; exposure to nature, view, and natural daylight has increased; the importance of ecological sustainability; and pandemic concerns have increased significantly in the wake of the coronavirus pandemic. Discussion of the results of this comprehensive review includes topics noticeably overlooked or underinvestigated in the 2005–2020 period and priorities for future research.