Clinical Characteristics, Treatment, and Outcomes of Critically Ill Patients With COVID-19: A Scoping Review

A growing number of studies on coronavirus disease 2019 (COVID-19) are becoming available, but a synthesis of available data focusing on the critically ill population has not been conducted. We performed a scoping review to synthesize clinical characteristics, treatment, and clinical outcomes among critically ill patients with COVID-19. Between 1/1/2020 and 5/15/2020, we identified high-quality clinical studies describing critically ill patients with a sample size >20 patients by performing daily searches of the World Health Organization and LitCovid databases on COVID-19. Two reviewers independently reviewed all abstracts (2785 unique articles), full-text (218 articles), and abstracted data (92 studies). 92 studies were included, including 61 from Asia, 16 from Europe, 10 from North and South America, as well as 5 multinational studies. Notable similarities among critically ill populations across all regions included a higher proportion of older males infected and with severe illness, high frequency of co-morbidities (hypertension, diabetes, and cardiovascular disease), abnormal chest imaging findings, and death secondary to respiratory failure. Differences in regions included newly identified complications (e.g., pulmonary embolism) and epidemiologic risk factors (e.g., obesity), less chest computed tomography imaging performed, and increased use of invasive mechanical ventilation (70-100% vs. 15-47% of ICU patients) in Europe and the US compared to Asia. Future research directions should include proof-of-mechanism studies to better understand organ injuries and large-scale collaborative clinical studies to evaluate the efficacy and safety of antivirals, antibiotics, IL-6 receptor blockers, and interferon. The current established predictive models require further verification in other regions outside China.
Article Highlights: 1. This scoping review is the first of its kind to synthesize the current literature focusing on COVID-19 patients with critical illness by analyzing 92 included studies from Asia, Europe, and North/South America. 2. Scoping reviews are valuable for summarizing existing knowledge, highlighting gaps in our understanding, and guiding future research directions. 3. Notable similarities among critically ill populations across all regions included a higher proportion of older males infected and with severe illness, high frequency of co-morbidities, abnormal chest imaging findings, and death secondary to respiratory failure. Differences in regions included newly identified complications (e.g., pulmonary embolism) and epidemiologic risk factors (e.g., obesity), and a longer stay in the ICU, less chest computed tomography imaging performed and increased use of mechanical ventilation (70-100% vs. 15-47% of ICU patients) in Europe and the US compared to China. 4. Future research directions include a need for studies to confirm the mechanism of organ injuries and large-scale collaborative clinical studies to evaluate the efficacy and safety of drugs. The current established predictive models require further verification in other regions outside China.