Answer:
If the baby is bradycardic (HR < 60 per minute) after 90seconds of resuscitation with a lower concentration of oxygen, oxygen concentration should be increased to 100% until recovery of a normal heart rate (Class IIb, LOE B). (Kattwinkel et al, Part 15: Neonatal Resuscitation, page S912)Research has shown that room air ventilation in neonates is superior to 100% oxygen and may result in lower mortality rates (Rabi, Rabi, & Yee, 2007).
It has been found that hyperoxia slows cerebral blood flow in neonates and exposure to 100% oxygen (even brief) causes long-term deficits in cerebral blood flow. High concentrations of oxygen are also related to free radical formation, which has a significant role in reperfusion injury following asphyxia (Davis, Tan, O’Donnell, & Schultz, 2004).References:Davis, P. G., Tan, A., O’Donnell, P. F., & Schultz, A. (2004). Resuscitation of newborn infants with 100% oxygen or air: A systematic review and meta-analysis. Lancet. 364, 1329-1333. Rabi, Y., Rabi, D., and Yee, W. (2007). Room air resuscitation of the depressed newborn: A systematic review and meta-analysis. Resuscitation. 72, 353-363.
*This question was updated on February 7th 2020