Document Classification

Section Type: METHODS

Text: These patients were randomly assigned to undergo one of four weaning techniques : intermittent mandatory ventilation, in which the ventilator rate was initially set at a mean (+ / - SD) of 10. 0 + / - 2. 2 breaths per minute and then decreased, if possible, at least twice a day, usually by 2 to 4 breaths per minute (29 patients) ; pressure-support ventilation, in which pressure support was initially set at 18. 0 + / - 6. 1 cm of water and then reduced, if possible, by 2 to 4 cm of water at least twice a day (37 patients) ; intermittent trials of spontaneous breathing, conducted two or more times a day if possible (33 patients) ; or a once-daily trail of spontaneous breathing (31 patients).