Noninvasive respiratory support and invasive ventilation in COVID‑19: Where do we stand today?

Abstract

The controversy surrounding ventilation in coronavirus disease 2019 (COVID-19) continues. Early in the pandemic it was postulated that the high intensive care unit (ICU) mortality may have been due to too early intubation. As the pandemic progressed recommendations changed and the use of noninvasive respiratory support (NIRS) increased; however, this did not result in a clear reduction in ICU mortality. Furthermore, large studies on optimal ventilation in COVID-19 are lacking. This review article summarizes the pathophysiological basis, the current state of the science and the impact of different treatment modalities on the outcome. Potential factors that could undermine the benefits of noninvasive respiratory support are discussed. The authors attempt to provide guidance in answering the difficult question of when is the right time to intubate?