OBJECTIVES: Since the beginning of the coronavirus disease 2019 pan-demic, hundreds of thousands of patients have been treated in ICUs across the globe. The severe acute respiratory syndrome–associated coronavirus 2 virus enters cells via the angiotensin-converting enzyme 2 receptor and activates several distinct inflammatory pathways, resulting in hematologic abnormalities and dysfunction in respiratory, cardiac, gastrointestinal renal, endocrine, dermatologic, and neurologic systems. This review summarizes the current state of research in coronavirus disease 2019 pathophysi-ology within the context of potential organ-based disease mechanisms and opportunities for translational research.

DATA SOURCES: Investigators from the Research Section of the Society of Critical Care Medicine were selected based on expertise in specific organ systems and research focus. Data were obtained from searches conducted in Medline via the PubMed portal, Directory of Open Access Journals, Excerpta Medica database, Latin American and Caribbean Health Sciences Literature, and Web of Science from an initial search from December 2019 to October 15, 2020, with a revised search to February 3, 2021. The medRxiv, Research Square, and clinical trial registries preprint servers also were searched to limit publication bias.

STUDY SELECTION: Content experts selected studies that included mechanism-based relevance to the severe acute respiratory syndrome–associated coronavirus 2 virus or coronavirus disease 2019 disease.

DATA EXTRACTION: Not applicable.

DATA SYNTHESIS: Not applicable.

CONCLUSIONS: Efforts to improve the care of critically ill coronavirus disease 2019 patients should be centered on understanding how severe acute respiratory syndrome–associated coronavirus 2 infection affects organ function. This review articulates specific targets for further research.

KEY WORDS: angiotensin-converting enzyme 2 receptor; coronavirus disease 2019; critical illness; pandemic; severe acute respiratory syndrome–associated coronavirus 2

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