Introduction
Pediatric asthma is the most common chronic lung disease in children worldwide and may cause serious morbidity and mortality1. The main focus of optimal asthma management is symptom control and prevention of exacerbations of the disease. However, 5% of children suffer from uncontrolled asthma despite maximal therapy, substantially contributing to asthma burden in this patient group2,3. Asthma exacerbations, defined as an acute deterioration requiring a prompt change in treatment, can be so severe that they require an emergency department (ED) visit, a hospital admission or even a pediatric intensive care unit (PICU) admission4,5. Severe acute asthma (SAA) is characterized by unresponsiveness to conventional therapy and requires PICU admission for intravenous therapy and sometimes even intubation6.
Usually, an asthma exacerbation is triggered by a viral infection, mediated through increased T2 inflammation7. However, external/environmental features such as pollen or air pollution are also common triggers4,8, influencing not only the occurrence of exacerbations but also, potentially, its pathobiology9,10. The Coronavirus Disease 2019 (COVID-19) pandemic is another example of an external factor influencing the risk for asthma exacerbations, especially during periods of major daily disruptions, such as lockdowns11. It has been suggested that the societal changes during the COVID-19 pandemic, in terms of the environment, medical practice and medication usage, have significantly influenced asthma management and outcomes12. While the incidence of asthma exacerbations in children during the COVID-19 pandemic has been evaluated11,13-15, the incidence of SAA requiring PICU admission and treatment during the pandemic is, to our knowledge, not known. Therefore, the aim of this study was to examine the trend of admissions for SAA at the PICU before and during the COVID-19 pandemic and to evaluate whether this could be linked to the COVID-19 restrictions or other external factors including environmental triggers.