COVID-19(97) Patient(71) mechanical ventilation(39) outcome(37) Mortality(35) ICU(33) intensive care(32) with COVID-19(30) ARDS(29) intensive care unit(29) respiratory(28) Respiratory failure(27) Critically ill(25) COVID-19 patient(24) hospital(24) Primary outcome(23) patients with COVID-19(22) median(22) age(22) syndrome(21) patients(20) significantly(20) acute respiratory distress(20) COVID-19 patients(20) determine(20) Oxygenation(17) death(17) conducted(17) SARS-CoV-2(17) Infection(16)