The main variables such as age, sex, blood gas indices: pH, PaCO2, PaO2, HCO3, PaO2/FiO2 ratio, lactate, vital signs parameters: heart rate, blood pressure, respiratory rate, SpO2 were collected at the timelines: admission, 30 minutes, 60 minutes, 120 minutes after AVM, before extubation and after extubation.