Spontaneous breathing trial (SBT). Patients with SpO2 ≥90% on FiO2 ≤0.4 and PEEP ≤5 cmH2O, no agitation, hemodynamically stable with norepinephrine ≤0.1 ug/kg/min or equivalent and at a stable or decreasing dose ≥6 hours and without any of the abovementioned criteria for switch to controlled ventilation will undergo a SBT: