PurposeWe aimed to analyze the changes in the disease spectrum data of a pediatric intensive care unit (PICU) in Nanjing, China, during the COVID-19 outbreak and explore a feasible plan for the treatment of critically ill children.MethodsThis retrospective study used data from our PICU from 1 January 2018 to 31 December 2020. Patient demographics, distribution of disease spectrum, results of etiological examinations, and the PICU length of stay (LOS) were compared during the COVID-19 period (2020) and the previous years (2018 and 2019).ResultsIn 2020, the number of PICU admissions was 46.8 and 47.8% lower than that in 2018 and 2019, respectively. There were significant differences in the number of patients in PICU among different age groups, and these differences were mainly found in children aged ConclusionsA striking decrease in the number of PICU admissions was observed during the COVID-19 outbreak, which caused a significant change in the PICU disease spectrum. Changes in the number and characteristics of patients admitted to PICUs should be considered for facilitating the effective working of PICUs during the COVID-19 pandemic.