Introduction: Preterm infants with inadequate breathing receive positive pressure ventilation (PPV) by mask with variable success. The authors examined recordings of PPV given to preterm infants in the delivery room for prevalence of mask leak and airway obstruction.
Methods and patients: The authors reviewed recordings of infants at <32 weeks' gestation born between February 2006 and March 2009. PPV was delivered with a T-piece or self-inflating bag and a round silicone face mask. Airway pressures and gas flow were recorded with a respiratory function monitor (RFM). Videos recorded from a web camera were used to review the resuscitation. The first 2 min of PPV were analysed for each infant. Obstruction was arbitrarily defined as a 75% reduction in delivered expired tidal volume (V(Te)) and significant face-mask leak as >75%.
Results: The authors analysed recordings of 56 preterm infants. Obstruction occurred in 14 (26%) recordings and leaks in 27 (51%). Both obstruction and mask leaks were seen in eight (14%) recordings, and neither was seen in 15 (27%). Obstruction occurred at a median (IQR) of 48 (24-60) s after the start of PPV. A median (range) of 22 (3-83) consecutive obstructed inflations were delivered. Face-mask leaks occurred from the first inflation in 19/27 (70%) and in the remaining eight at a median (IQR) of 30 (24-46) s after the start of PPV. A median (range) of 10 (3-117) consecutive inflations with a leak >75% were delivered.
Conclusion: Airway obstruction and face-mask leak are common during the first 2 min of PPV. An RFM enables detection of important airway obstruction and mask leak.