Surging critical care capacity for COVID-19: Key now and in the future

The COVID-19 pandemic has shocked health systems worldwide, with visible impacts on intensive care units and emergency departments. The concept of "surge capacity" should be analyzed within this context as this crisis could be seen as an opportunity to improve the knowledge base of intensive care units and emergency departments. We reflected, based on our experience from work at the frontlines, on health service planning and with epidemiological data, about the importance of surging critical care capacity for COVID, now and as lessons for the future. We summarize and relate virus clinical characteristics, epidemiological patterns and critical care surge capacity as important factors to consider for effective health systems response. Some practical aspects are described, but also the role that mathematical models can play to improve intensive care units surge capacity by considering its importance as a predictor of needs according to epidemiological patterns. Also, in the transitional phase, we consider the importance of coexisting COVID-19 and non-covid-19 health care services, and the importance of a new surge capacity for postponed activities. In this new transitional phase, also emergency departments will have to adapt their surge capacity for a rebound effect due to delayed visits from non-COVID-19 health conditions during the pandemic. Health systems and society must remain vigilant for potential resurgence of cases as measures are relaxed to restart the economy and a new normal. Emergency departments and intensive care units have to develop surge strategies to deal together with COVID-19 and non-COVID-19 flow of patients.