COVID-19 pandemic in Southern Brazil: Hospitalizations, intensive care unit admissions, lethality rates, and length of stay between March 2020 and April 2022

Coronavirus disease 2019 (COVID-19) pandemic spread rapidly with more than 515 million cases and 6.2 million deaths. Epidemiological factors are important for understanding the state of the pandemic. This study aims to evaluate the hospitalizations, intensive care unit (ICU) admissions, and lethality from March 2020 to April 2022. Data were collected from a hospital in Porto Alegre city, southern Brazil. The Mann-Whitney, analysis of variance, and Kruskal-Wallis tests were used to compare quantitative variables. Categorical variables were compared by Pearson’s χ^{2} test. p values <0.05 for all tests were considered significant. Were observed 3784 hospitalizations. Males were 51.4% and the age was 60.4± 20.3. Intensive care unit (ICU) patients were 31.2%, the median length of stay (LOS) was 9.0 and lethality was 13.3%. ICU lethality was 34.5% versus 4.6% in other inpatients (p < 0.01). The LOS of ICU patients was 22.0 versus 7.0 in other inpatients (p < 0.01). The first peak (July-Novemebr 2020) showed ICU occupancy of 79.1%. The second peak (December 2020-June 2021) with 91.6% occupancy. The third peak January-March 2022 with 81.0% occupancy (p < 0.01). Lethality rates were 10.3% in 2020, 14.9% in 2021 and 15.4% in 2022 (p < 0.01). In conclusion, the ICU occupancy rate was higher in 2021 and the lethality rates of ICU patients were high during pandemic years (10.3% in 2020, 14.9% in 2021, and 15.2% in 2022). The lethality of these patients ranged from 25.0% in March to 21.8% in December 2020, from 20.9% in January 22.2% in Decemebr 2021, and 35.7% in January 2022 to 21.4% in April 2022. These data demonstrate that COVID-19 is a critical illness, even in a private hospital setting.