title: Effect of body position on ventilation distribution in preterm infants on continuous positive airway pressure.
abstract: BACKGROUND
  Although continuous positive airway pressure is used extensively in neonatal intensive care units, and despite the belief that positioning is considered vital to the maintenance of good lung ventilation, no data exist on regional ventilation distribution in infants on continuous positive airway pressure ventilatory support.
  
  
  OBJECTIVE
  To investigate the effect of body position on regional ventilation in preterm infants on continuous positive airway pressure ventilatory support using electrical impedance tomography.
  
  
  METHODS
  Randomized crossover study design.
  
  
  METHODS
  Neonatal intensive care unit.
  
  
  METHODS
  Twenty-four preterm infants on continuous positive airway pressure were compared to six spontaneously breathing preterm infants.
  
  
  METHODS
  Random assignment of the order of the positions supine, prone, and quarter prone.
  
  
  RESULTS
  Changes in global and regional lung volume were measured with electrical impedance tomography. Although there were no differences between positions, regional tidal volume was increased in the posterior compared with the anterior lung (p < .01) and in the right compared with the left lung (p < .03) in both the spontaneously breathing infants and in the infants on continuous positive airway pressure. The posterior lung filled earlier than the anterior lung in the spontaneously breathing infants (p < .02), whereas in the infants on continuous positive airway pressure the right lung filled before the left lung (p < .01). There was more ventilation inhomogeneity in the infants on continuous positive airway pressure than in the healthy infants (p < .01).
  
  
  CONCLUSIONS
  This study presents the first results on regional ventilation distribution in preterm infants on continuous positive airway pressure using electrical impedance tomography. Gravity had little impact on regional ventilation distribution in preterm infants on continuous positive airway pressure or in spontaneously breathing infants in the supine or prone position, indicating that ventilation distribution in preterm infants is not gravity-dependent but follows an anatomical pattern. AUSTRALIA NEW ZEALAND CLINICAL TRIALS REGISTRY:: ACTRN12606000210572.
authors.affiliation: Paediatric Critical Care Research Group, Paediatric Intensive Care Unit, Mater Health Services, South Brisbane, QLD, Australia. judith. hough@mater.org.au
authors.forename: Judith L
authors.initials: JL
authors.lastname: Hough
authors.forename: Leanne
authors.initials: L
authors.lastname: Johnston
authors.forename: Sandy G
authors.initials: SG
authors.lastname: Brauer
authors.forename: Paul G
authors.initials: PG
authors.lastname: Woodgate
authors.forename: Trang M T
authors.initials: TM
authors.lastname: Pham
authors.forename: Andreas
authors.initials: A
authors.lastname: Schibler
mesh_terms: D045422:Continuous Positive Airway Pressure; D018592:Cross-Over Studies; D017097:Electric Impedance; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007363:Intensive Care Units, Neonatal; D008168:Lung / Q000502:physiology; D008297:Male; D011187:Posture / Q000502:physiology*; D016684:Prone Position / Q000502:physiology; D012121:Respiration, Artificial; D015656:Respiratory Mechanics; D016683:Supine Position / Q000502:physiology; D014054:Tomography / Q000379:methods