Days until respiratory recovery. The O2 saturation will be measured twice daily for all patients by a fingertip pulse oximeter. Primary outcome is achieved when O2 saturation is equal or grater than 93% in room air.

Days until respiratory recovery. The O2 saturation will be measured twice daily for all patients by a fingertip pulse oximeter. Primary outcome is achieved when O2 saturation is equal or grater than 93% in room air.