In 40 patients dependent on noninvasive ventilation ( VC , 1611 % predicted ; age , 204 yr ) and in 20 healthy control subjects , insufflation capacity ( IC ) was measured during titration from 10 to maximum 40 mbar using intermittent positive pressure breathing ( IPPB ) or the lung insufflation assist maneuver ( LIAM ) of the VENTIlogic LS ventilator .