Oxygen supplementation in the delivery room: T-piece resuscitator cap open or occluded?

Updated neonatal resuscitation guidelines for free-flow oxygen administration with a T-piece resuscitator recommend higher gas flow and an open T-piece cap. We aimed to determine the effect of gas inflow rate and cap occlusion on oxygen delivery through a T-piece resuscitator. Using a NeoPuff™ T-piece, oxygen inflow was randomly adjusted from 4 to 10 liters per minute (LPM). Gas outflow and oxygen concentration were measured with the T-piece cap open and occluded. Data were analyzed with repeated measures 2-way ANOVA. Gas outflow was significantly decreased with the T-piece cap open compared with occluded at each inflow rate (p < 0.001). There was no difference in oxygen concentration of the outflow gas. Gas flow from the T-piece is affected by the inflow rate and cap occlusion but oxygen concentration is not. To deliver 5 LPM of free-flow oxygen with the cap open, a minimum of 8 LPM gas inflow is required.