The University of Louisville Journal of Respiratory Infections

Article Title

Severe COVID-19


Introduction: There are substantial variabilities of the clinical characteristics and outcomes of severe coronavirus disease (COVID-19) creating difficulty to do an optimal assessment of this condition. We reviewed the current English literature to quantify the findings of baselines characteristics and health outcomes of patients with severe COVID-19 primarily with acute respiratory distress syndrome (ARDS).

Methods: We examined only studies that assessed patients with proven COVID-19 by RT-PCR by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) with at least one of the following severity criteria: severe COVID-19, treated in the ICUs, ARDS and/or invasive mechanical ventilation (IMV) treatment. We assessed the quality of the studies according to the National Heart, Lung and Blood Institute, Study Quality Assessment Tools.

Results: Seven of 39 studies fulfilled the inclusion criteria. These seven studies included a total 1,863 patients, the median age was 63.5 years (49-70). A total 370 (19.8%) were females. Four studies were from the USA, two from China and one from Italy. Comorbidities were reported in six studies. Fever was reported in five studies and it was present in 159 out of 272 patients. Cough and shortness of breath (SOB) were reported in four studies, they were present in 111 out of 142 and 100 out of 142 of patients respectively. The median of total lymphocytes was reported in five studies with a range of 400 – 889/ul. IMV ranged from 15% to 100% and mortality ranged from 14.6% to 88%. In a subgroup analysis by countries, patients from the US showed more comorbidities, higher percent of IMV and mortality. The assessment quality score of the seven studies was (5), for a total score of (8).

Conclusions: Severe COVID-19 was predominantly seen in male patients who were 60 years and older associated with comorbidities. Most of the patients were admitted at the ICU, needed IMV support due to ARDS and had a mortality range of 14.6-88%.


The author(s) received no specific funding for this work.



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Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.



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