title: The interrelationship of recruitment maneuver at birth, antenatal steroids, and exogenous surfactant on compliance and oxygenation in preterm lambs.
abstract: To describe the interrelationship between antenatal steroids, exogenous surfactant, and two approaches to lung recruitment at birth on oxygenation and respiratory system compliance (Cdyn) in preterm lambs.
  
  
  
  Lambs (n = 63; gestational age 127 ± 1 d) received either surfactant at 10-min life (Surfactant), antenatal corticosteroids (Steroid), or neither (Control). Within each epoch lambs were randomly assigned to a 30-s 40 cmH2O sustained inflation (SI) or an initial stepwise positive end-expiratory pressure (PEEP) open lung ventilation (OLV) maneuver at birth. All lambs then received the same management for 60-min with alveolar-arterial oxygen difference (AaDO2) and Cdyn measured at regular time points.
  
  
  
  Overall, the OLV strategy improved Cdyn and AaDO2 (all epochs except Surfactant) compared to SI (all P < 0.05; two-way ANOVA). Irrespective of strategy, Cdyn was better in the Steroid group in the first 10 min (all P < 0.05). Thereafter, Cdyn was similar to Steroid epoch in the OLV + Surfactant, but not SI + Surfactant group. OLV influenced the effect of steroid and surfactant (P = 0.005) on AaDO2 more than SI (P = 0.235).
  
  
  
  The antenatal state of the lung influences the type and impact of a recruitment maneuver at birth. The effectiveness of surfactant maybe enhanced using PEEP-based time-dependent recruitment strategies rather than approaches solely aimed at initial lung liquid clearance.
authors: Neonatal Research Group, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.|Department of Neonatology, The Royal Children's Hospital, Melbourne, Victoria, Australia.|Neonatal Research Group, The Royal Women's Hospital, Melbourne, Victoria, Australia.|Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia.
authors: David G
authors: 0000-0003-1522-4691
authors: DG
authors: Tingay
authors: Neonatal Research Group, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.|Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia.
authors: Anushi
authors: A
authors: Rajapaksa
authors: Neonatal Research Group, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.
authors: Karen
authors: K
authors: McCall
authors: Neonatal Research Group, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.
authors: Cornelis E E
authors: CE
authors: Zonneveld
authors: Neonatal Research Group, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.
authors: Don
authors: D
authors: Black
authors: Neonatal Research Group, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.
authors: Elizabeth
authors: E
authors: Perkins
authors: Neonatal Research Group, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.|Department of Neonatology, The Royal Children's Hospital, Melbourne, Victoria, Australia.
authors: Magdy
authors: M
authors: Sourial
authors: Neonatal Research Group, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.|NICU, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico-Università degli Studi di Milano, Milano, Italy.
authors: Anna
authors: A
authors: Lavizzari
authors: Neonatal Research Group, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.|Neonatal Research Group, The Royal Women's Hospital, Melbourne, Victoria, Australia.|Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia.
authors: Peter G
authors: 0000-0001-6742-7314
authors: PG
authors: Davis
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000818:Animals; D000831:Animals, Newborn; D005260:Female; D008170:Lung Compliance / Q000187:drug effects; D008297:Male; D010100:Oxygen / Q000502:physiology*; D011175:Positive-Pressure Respiration; D011663:Pulmonary Surfactants / Q000627:therapeutic use; D015656:Respiratory Mechanics / Q000187:drug effects*; D012137:Respiratory System; D012756:Sheep; D034561:Sheep, Domestic; D013256:Steroids / Q000627:therapeutic use*
chemical_list: D000305:Adrenal Cortex Hormones; D011663:Pulmonary Surfactants; D013256:Steroids; D010100:Oxygen