title: Effect of body position on ventilation distribution in ventilated preterm infants.
abstract: BACKGROUND
  Positioning is considered vital to the maintenance of good lung ventilation by optimizing oxygen transport and gas exchange in ventilated premature infants. Previous studies suggest that the prone position is advantageous; however, no data exist on regional ventilation distribution for this age group.
  
  
  OBJECTIVE
  To investigate the effect of body position on regional ventilation distribution in ventilated and nonventilated preterm infants using electrical impedance tomography.
  
  
  METHODS
  Randomized crossover study design.
  
  
  METHODS
  Neonatal ICU.
  
  
  METHODS
  A total of 24 ventilated preterm infants were compared with six spontaneously breathing preterm infants.
  
  
  METHODS
  Random assignment of the order of the positions supine, prone, and quarter prone.
  
  
  RESULTS
  Ventilation distribution was measured with regional impedance amplitudes and global inhomogeneity indices using electrical impedance tomography. In the spontaneously breathing infants, regional impedance amplitudes were increased in the posterior compared with the anterior lung (p < 0.01) and in the right compared with the left lung (p = 0.03). No differences were found in the ventilated infants. Ventilation was more inhomogeneous in the ventilated compared with the healthy infants (p < 0.01). Assessment of temporal regional lung filling showed that the posterior lung filled earlier than the anterior lung in the spontaneously breathing infants (p < 0.02) whereas in the in the ventilated infants the right lung filled before the left lung (p < 0.01).
  
  
  CONCLUSIONS
  In contrast to previous studies showing that ventilation is distributed to the nondependent lung in infants and children, this study shows that gravity has little effect on regional ventilation distribution.
authors: Critical Care of the Newborn Program, Mater Medical Research Institute, South Brisbane, QLD, Australia. judith.hough@mater.org.au
authors: Judith L
authors: JL
authors: Hough
authors: Leanne
authors: L
authors: Johnston
authors: Sandy
authors: S
authors: Brauer
authors: Paul
authors: P
authors: Woodgate
authors: Andreas
authors: A
authors: Schibler
mesh_terms: D000704:Analysis of Variance; D018592:Cross-Over Studies; D017097:Electric Impedance; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007385:Intermittent Positive-Pressure Ventilation / Q000379:methods*; D008297:Male; D010100:Oxygen / Q000097:blood; D056888:Patient Positioning; D047928:Premature Birth; D016684:Prone Position / Q000502:physiology; D012123:Pulmonary Ventilation / Q000502:physiology*; D012127:Respiratory Distress Syndrome, Newborn / Q000628:therapy; D016683:Supine Position / Q000502:physiology; D014054:Tomography
chemical_list: D010100:Oxygen