Helium^during expiration:VFr/PPres:Pt:Gas delivery system.expiratory limb:Qn
helium^during expiration:vfr/ppres:pt:gas delivery system.expiratory limb:qn
Helium^during expiration:VFr/PPres:Pt:Gas delivery system.expiratory limb:Qn
helium^during expiration:vfr/ppres:pt:gas delivery system.expiratory limb:qn