title: Effectiveness of individualized lung recruitment strategies at birth: an experimental study in preterm lambs.
abstract: Respiratory transition at birth involves rapidly clearing fetal lung liquid and preventing efflux back into the lung while aeration is established. We have developed a sustained inflation (SIOPT) individualized to volume response and a dynamic tidal positive end-expiratory pressure (PEEP) (open lung volume, OLV) strategy that both enhance this process. We aimed to compare the effect of each with a group managed with PEEP of 8 cmH2O and no recruitment maneuver (No-RM), on gas exchange, lung mechanics, spatiotemporal aeration, and lung injury in 127 ± 1 day preterm lambs. Forty-eight fetal-instrumented lambs exposed to antenatal steroids were ventilated for 60 min after application of the allocated strategy. Spatiotemporal aeration and lung mechanics were measured with electrical impedance tomography and forced-oscillation, respectively. At study completion, molecular and histological markers of lung injury were analyzed. Mean (SD) aeration at the end of the SIOPTand OLV groups was 32 (22) and 38 (15) ml/kg, compared with 17 (10) ml/kg (180 s) in the No-RM (P = 0.024, 1-way ANOVA). This translated into better oxygenation at 60 min (P = 0.047; 2-way ANOVA) resulting from better distal lung tissue aeration in SIOPTand OLV. There was no difference in lung injury. Neither SIOPTnor OLV achieved homogeneous aeration. Histological injury and mRNA biomarker upregulation were more likely in the regions with better initial aeration, suggesting volutrauma. Tidal ventilation or an SI achieves similar aeration if optimized, suggesting that preventing fluid efflux after lung liquid clearance is at least as important as fluid clearance during the initial inflation at birth.
authors.affiliation: Neonatal Research, Murdoch Children's Research Institute, Parkville, Australia; david.tingay@rch.org.au.|Neonatology, The Royal Children's Hospital, Parkville, Australia.|Neonatal Research, The Royal Women's Hospital, Parkville, Australia.|Department of Paediatrics, University of Melbourne, Melbourne, Australia.
authors.forename: David G
authors.identifier: http://orcid.org/0000-0003-1522-4691
authors.initials: DG
authors.lastname: Tingay
authors.affiliation: Neonatal Research, Murdoch Children's Research Institute, Parkville, Australia.|Department of Paediatrics, University of Melbourne, Melbourne, Australia.
authors.forename: Anushi
authors.initials: A
authors.lastname: Rajapaksa
authors.affiliation: TBM Laboratory, Dipartimento di Elettronica, Informazione e Ingegneria Biomedica-DEIB, Politecnico di Milano University, Milano, Italy.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Zannin
authors.affiliation: Neonatal Research, Murdoch Children's Research Institute, Parkville, Australia.|Department of Paediatrics, University of Melbourne, Melbourne, Australia.
authors.forename: Prue M
authors.initials: PM
authors.lastname: Pereira-Fantini
authors.affiliation: TBM Laboratory, Dipartimento di Elettronica, Informazione e Ingegneria Biomedica-DEIB, Politecnico di Milano University, Milano, Italy.
authors.forename: Raffaele L
authors.initials: RL
authors.lastname: Dellaca
authors.affiliation: Neonatal Research, Murdoch Children's Research Institute, Parkville, Australia.|Neonatology, The Royal Children's Hospital, Parkville, Australia.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Perkins
authors.affiliation: Neonatal Research, Murdoch Children's Research Institute, Parkville, Australia.
authors.forename: Cornelis E E
authors.initials: CE
authors.lastname: Zonneveld
authors.affiliation: Systems and Computer Engineering, Carleton University, Ottawa, Canada.
authors.forename: Andy
authors.initials: A
authors.lastname: Adler
authors.affiliation: Neonatal Research, Murdoch Children's Research Institute, Parkville, Australia.
authors.forename: Don
authors.initials: D
authors.lastname: Black
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University Medical Centre Schleswig-Holstein, Campus Kiel, Kiel, Germany.
authors.forename: Inéz
authors.initials: I
authors.lastname: Frerichs
authors.affiliation: Neonatal Research, Murdoch Children's Research Institute, Parkville, Australia.|NICU, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico-Università degli Studi di Milano, Milano, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Lavizzari
authors.affiliation: Neonatal Research, Murdoch Children's Research Institute, Parkville, Australia.
authors.forename: Magdy
authors.initials: M
authors.lastname: Sourial
authors.affiliation: Fraunhofer Project Group for Automation in Medicine and Biotechnology, Mannheim, Germany; and.
authors.forename: Bartłomiej
authors.initials: B
authors.lastname: Grychtol
authors.affiliation: NICU, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico-Università degli Studi di Milano, Milano, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Mosca
authors.affiliation: Neonatal Research, Murdoch Children's Research Institute, Parkville, Australia.|Neonatal Research, The Royal Women's Hospital, Parkville, Australia.|Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Australia.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Davis
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D003187:Compliance; D017097:Electric Impedance; D008168:Lung / Q000473:pathology / Q000503:physiopathology*; D055370:Lung Injury / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D010100:Oxygen / Q000378:metabolism; D047928:Premature Birth / Q000503:physiopathology*; D011312:Pressure; D012119:Respiration; D012121:Respiration, Artificial; D015656:Respiratory Mechanics / Q000502:physiology; D012756:Sheep; D013990:Tidal Volume
chemical_list: D010100:Oxygen
keywords: infant; lung mechanics; open lung ventilation; preterm; regional lung injury; sustained inflation