In the current study, pressure assist/control ventilation (P-ACV) mode was used in the control group because adaptive support ventilation (ASV) also works as a pressure-controlled mode in passive patients. When patients met readiness to wean criteria, they were tested immediately with a spontaneous breathing trial (SBT) with a T-tube for extubation. Patients who fail the initial SBT should receive a nonfatiguing mode of mechanical ventilation (generally either assist-control or PSV) as suggested in the Weaning Task Force of the European Respiratory Society. We selected P-ACV as the ventilation mode in patients failing the first SBT. The only difference regarding synchronization between P-ACV and PSV in spontaneously breathing patients is the cycling parameter (time in P-ACV and flow in PSV). Theoretically, PSV could be selected as the ventilation mode in these patients, but we believe that if the cycling parameter is set with caution and adjusted according to patients’ needs in P-ACV, synchrony would not be inferior compared with PSV. There are also data regarding better patient ventilator interaction or hemodynamic effects with time cycling compared with flow cycling in patients undergoing noninvasive ventilation., Although the clinicians in charge were cautious when adjusting the cycling parameter (inspiratory time) in P-ACV according to patient ventilator synchrony, the automatic switch to PSV provided by ASV with no intervention from the clinician as soon as the patient triggered the breath may have had an impact on the outcome. Even if patients in the P-ACV mode were switched to PSV, this intervention could be have been delayed owing to late recognition of the actively breathing patient, especially during night shifts in centers with a low ratio of nurses to patients, as in ours. We think that this is one advantage of automatic closed-loop modes in these kinds of ICUs with a high workload. There are also data showing that extubation readiness cannot be recognized in a timely manner in at least 15% of patients recovering from respiratory failure, even in the presence of a ventilation protocol. In our study, we could not evaluate physiologic data that could affect patient ventilator interaction because of technical limitations, so this issue deserves further research to be clarified.