title: Effects of a sustained inflation in preterm infants at birth.
abstract: OBJECTIVE
  To assess the clinical effect of an initial sustained inflation of 10 seconds and 25 cmH2O in preterm infants at birth.
  
  
  METHODS
  In this observational study inflation pressures and tidal volumes were recorded with the use of respiratory function monitoring of preterm infants <32 weeks' gestation receiving a sustained inflation. Inspiratory tidal volume (Vti) and expiratory tidal volume (Vte) of sustained inflation and cumulative Vti and Vte of breaths during sustained inflation were determined. Heart rate and oxygen saturation were measured before and after the sustained inflation.
  
  
  RESULTS
  Seventy infants were included (median [IQR]: gestational age 29 [27-30] weeks). Mean (SD) sustained inflation duration was 10.5 seconds (2.9 seconds) with positive inflation pressure 24.2 cmH2O (2.3 cmH2O) and positive end-expiratory pressure 6.0 cmH2O (1.8 cmH2O). In 20 of 70 infants, no volumes were delivered during the sustained inflation because of mask leak. No leak occurred in 50 of 70 infants, of whom 36 of 50 breathed during the sustained inflation. In 14 of the infants who did not breathe, Vti and Vte were 0.9 mL/kg (0.4-2.7 mL/kg) and 0.6 mL/kg (0.1-2.0 mL/kg) with a functional residual capacity (FRC) gain of 0.0 (-0.5 to 0.6) mL/kg. In 36 of 50 infants who breathed during the sustained inflation, Vti was 2.9 mL/kg (0.9-9.2 mL/kg) and Vte 3.8 mL/kg (1.0-5.9 mL/kg), whereas cumulative Vti of breaths was 16.4 mL/kg (6.8-23.3 mL/kg) and cumulative Vte of breaths was 5.8 mL/kg (1.2-16.8 mL/kg) with an FRC gain of 7.1 mL/kg (1.7-15.9 mL/kg). Heart rate and oxygen saturation did not increase immediately after the sustained inflation.
  
  
  CONCLUSIONS
  A sustained inflation of 10 seconds and 25 cmH2O in preterm infants at birth was not effective unless infants breathed. Although large mask leak accounted for approximately one-third of failures, as FRC gain was only associated with breathing, we speculate that active glottic adduction may be responsible for most failures.
authors.affiliation: Division of Neonatology, Department of Pediatrics, Leiden University Medical Center, Leiden, The Netherlands. Electronic address: J.J.van_Vonderen@lumc.nl.
authors.forename: Jeroen J
authors.initials: JJ
authors.lastname: van Vonderen
authors.affiliation: The Ritchie Center, Monash Institute for Medical Research, Monash University, Clayton, Victoria, Australia.
authors.forename: Stuart B
authors.initials: SB
authors.lastname: Hooper
authors.affiliation: Division of Neonatology and Pediatric Critical Care, Department of Pediatric and Adolescent Medicine, University Medical Center, Ulm, Germany.
authors.forename: Helmut D
authors.initials: HD
authors.lastname: Hummler
authors.affiliation: Division of Neonatology, Department of Pediatrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Enrico
authors.initials: E
authors.lastname: Lopriore
authors.affiliation: Division of Neonatology, Department of Pediatrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Arjan B
authors.initials: AB
authors.lastname: te Pas
mesh_terms: D005260:Female; D005652:Functional Residual Capacity / Q000502:physiology; D005865:Gestational Age; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D007235:Infant, Premature, Diseases / Q000503:physiopathology*; D007327:Insufflation / Q000379:methods*; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008397:Masks; D011175:Positive-Pressure Respiration; D011247:Pregnancy; D012129:Respiratory Function Tests; D013990:Tidal Volume / Q000502:physiology