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

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.