Effects of a Sustained Inflation in Preterm Infants at Birth

Objective To assess the clinical effect of an initial sustained inflation of 10 seconds and 25 cmH 2 O in preterm infants at birth. Study design In this observational study inflation pressures and tidal volumes were recorded with the use of respiratory function monitoring of preterm infants 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 cmH 2 O (2.3 cmH 2 O) and positive end-expiratory pressure 6.0 cmH 2 O (1.8 cmH 2 O). 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 cmH 2 O 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.