title: Proportional assist versus assist control ventilation in premature infants.
abstract: During proportional assist ventilation (PAV), the applied pressure is servo-controlled based on continuous input from the infant's breathing. In addition, elastic and resistive unloading can be employed to compensate for the abnormalities in the infant's lung mechanics. The aim of this study was to test the hypothesis that in very prematurely born infants remaining ventilated beyond the first week, PAV compared to assist control ventilation (ACV) would be associated with superior oxygenation. A randomised crossover study was undertaken. Infants were studied for 4 hours each on PAV and ACV in random order; at the end of each 4-h period, the oxygenation index (OI) was calculated. Eight infants, median gestational age of 25 (range 24-33) weeks, were studied at a median of 19 (range 10-105) days. It had been intended to study 18 infants but as all the infants had superior oxygenation on PAV (p = 0.0039), the study was terminated after recruitment of eight infants. The median inspired oxygen concentration (p = 0.049), mean airway pressure (p = 0.012) and OI (p = 0.012) were all lower on PAV.
  
  
  CONCLUSIONS
  These results suggest that PAV compared to ACV is advantageous in improving oxygenation for prematurely born infants with evolving or established BPD.
  
  
  BACKGROUND
  During proportional assist ventilation (PAV), the applied pressure is servo controlled throughout each spontaneous breath. Elastic and resistive unloading can compensate for the infant's abnormalities in lung mechanics.
  
  
  BACKGROUND
  In a randomised crossover study, infants with evolving/established BPD were studied on PAV and ACV each for 4 h. The oxygenation index was significantly lower on PAV in all infants studied.
authors.affiliation: Neonatal Intensive Care Centre, King's College Hospital, London, UK. sandeep.shetty1@nhs.net.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Shetty
authors.affiliation: Division of Asthma, Allergy and Lung Biology, MRC Centre for Allergic Mechanisms in Asthma, King's College London, London, UK. prashanth.bhat@kcl.ac.uk.
authors.forename: Prashanth
authors.initials: P
authors.lastname: Bhat
authors.affiliation: Neonatal Intensive Care Centre, King's College Hospital, London, UK. annhickey@nhs.net.
authors.forename: Ann
authors.initials: A
authors.lastname: Hickey
authors.affiliation: Division of Health and Social Care Research, King's College London, London, UK. janet.peacock@kcl.ac.uk.|NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust and King's College London, London, UK. janet.peacock@kcl.ac.uk.
authors.forename: Janet L
authors.initials: JL
authors.lastname: Peacock
authors.affiliation: Division of Asthma, Allergy and Lung Biology, MRC Centre for Allergic Mechanisms in Asthma, King's College London, London, UK. anthony.milner@kcl.ac.uk.
authors.forename: Anthony D
authors.initials: AD
authors.lastname: Milner
authors.affiliation: Division of Asthma, Allergy and Lung Biology, MRC Centre for Allergic Mechanisms in Asthma, King's College London, London, UK. anne.greenough@kcl.ac.uk.|NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust and King's College London, London, UK. anne.greenough@kcl.ac.uk.
authors.forename: Anne
authors.initials: A
authors.lastname: Greenough
mesh_terms: D001997:Bronchopulmonary Dysplasia / Q000628:therapy; D006801:Humans; D062071:Infant, Extremely Premature; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000628:therapy*; D059725:Interactive Ventilatory Support
keywords: Assist control ventilation; Oxygenation; Proportional assist ventilation