Ali Houeijeh1,2, Pierre Tourneux1,3, Sébastien Mur4, Estelle Aubry1,5, Romain Viard6, Dyuti Sharma1,5, Laurent Storme1,4. 1. EA4489 "Perinatal Environment and Health", FHU "1000 days 4 Health", University of Lille - Nord de France, Lille, France. 2. Pediatric Cardiology Unit, Department of Pediatrics, Lille University Hospital, Lille, France. 3. Department of Neonatology, Maternity, Amiens University Hospital, Amiens, France. 4. Department of Neonatology and Maternity, Jeanne de Flandre Hospital, Lille University Hospital, Lille, France. 5. Pediatric Surgery Unit, Department of Pediatrics, Lille University Hospital, Lille, France. 6. Plateforme Imagerie du Vivant, University of Lille, Nord de France, Lille, France.
Abstract
BACKGROUND: Postnatal adaptation requires liquid clearance and lung aeration. However, their relative contribution to the expansion of functional residual capacity (FRC) has not been fully investigated. We studied evolution of lung liquid removal and lung aeration after birth in preterm lambs. METHODS: Lung liquid content and lung volume were assessed at birth and every 30 min over 2 h using magnetic resonance imaging (MRI) in three groups of lambs delivered by cesarean: preterm, late preterm, and late preterm with antenatal steroids. Lung function and mechanics of the respiratory system were also measured. RESULTS: Lung liquid content increased by approximately 30% in the preterm group (P < 0.05), whereas it did not change significantly in the late preterm lambs. Antenatal steroids induced a 50% drop in the lung liquid content (P < 0.05). Total lung volume increased in all groups (P < 0.05) but was higher in the late preterm + steroids group relative to other groups (P < 0.05). Compliance and resistances of the respiratory system were significantly correlated with lung liquid content (P < 0.05). CONCLUSION: FRC expansion results mainly from an increase in lung volume rather than a decrease in lung liquid in preterm and late preterm lambs. Antenatal steroids promote FRC expansion through increases in lung volume and liquid clearance.
BACKGROUND: Postnatal adaptation requires liquid clearance and lung aeration. However, their relative contribution to the expansion of functional residual capacity (FRC) has not been fully investigated. We studied evolution of lung liquid removal and lung aeration after birth in preterm lambs. METHODS: Lung liquid content and lung volume were assessed at birth and every 30 min over 2 h using magnetic resonance imaging (MRI) in three groups of lambs delivered by cesarean: preterm, late preterm, and late preterm with antenatal steroids. Lung function and mechanics of the respiratory system were also measured. RESULTS: Lung liquid content increased by approximately 30% in the preterm group (P < 0.05), whereas it did not change significantly in the late preterm lambs. Antenatal steroids induced a 50% drop in the lung liquid content (P < 0.05). Total lung volume increased in all groups (P < 0.05) but was higher in the late preterm + steroids group relative to other groups (P < 0.05). Compliance and resistances of the respiratory system were significantly correlated with lung liquid content (P < 0.05). CONCLUSION: FRC expansion results mainly from an increase in lung volume rather than a decrease in lung liquid in preterm and late preterm lambs. Antenatal steroids promote FRC expansion through increases in lung volume and liquid clearance.
Authors: Liina Süvari; Otto M Helve; M Anneli Kari; L Ursula Turpeinen; P Anniina Palojärvi; Markus J Leskinen; Sture Andersson; A Cecilia Janér Journal: Pediatr Res Date: 2020-07-14 Impact factor: 3.756