Table 2: Evolution of arterial blood gases in the ICU.

0 h (FiO2: 0.3)4 h* (FiO2: 0.6)9 h (FiO2: 0.8)10 h (FiO2: 0.6)12 h (FiO2: 0.5)48 h**(FiO2: 0.4)

pH7.2417.2427.1957.2637.357.396
PaCO2 (mmHg)46.135.529.331.131.438.8
PaO2 (mmHg)68.672.5207188217134
HCO−3 (mEq/L)16.715.512.615.1 18.823.8
Lactate (mmol/L)4.35.79.46.73.40.8

Intubated and invasive mechanical ventilation was initiated.
Extubated.