Time needed to achieve changes in oxygen concentration at the T-Piece resuscitator during respiratory support in preterm infants in the delivery room

Abstract

Objective: To measure the time needed to achieve changes in fraction of inspired oxygen concentration (FiO2) from the oxygen blender to the facemask during simulated neonatal resuscitation. Method: Two oxygen analyzers were placed at each end of the T-Piece. During simulated ventilation, the duration to achieve the set oxygen concentration at the facemask was measured. This was repeated at different gas flow rates (5 L/min, 8 L/min or 10 L/min) and different FiO2 changes (0.21 to 1.0 to 0.21, with stepwise increases and decreases in 0.05, 0.1 and 0.2 increments). Results: A total of 1134 measurements (378 measurements for each flow) were recorded. Overall, the mean (± SD) time required to achieve FiO2 changes at 5 L/min, 8 L/min and 10 L/min was 36±15 s, 31±14 s and 28±14 s, respectively. Conclusion: There was a lag time of approximately 30 s to achieve the FiO2 at the facemask. This delay needs to be considered when making serial adjustments to FiO2 during neonatal resuscitation.