Early Verticalization of the Patient With Acute Respiratory Distress Syndrome: Assessment of Feasibility and Safety.

"The randomly selected study sequence (Arm1, Arm2, Arm3 or Arm4) will begin after the supine roll-over at the end of the first PP session (out-of-study sequence). This allows all patients to initially have the positioning technique that has been proven beneficial in ARDS.~The chronology of the treatment periods in each of the 4 arms allocated by randomization will be as follows: Each PP must be started within 4 to 8 hours after the end of the previous PP or after the end of the verticalization that just preceded it. Each verticalization must be performed within 4 to 8 hours after the end of the previous PP or the previous verticalization. Each PP period will last between 12 and 20 hours."