Found at MEdscape:
Oxygen Saturation in Preterm Infants: Hitting the Target
Oxygen Saturation Targeting in Preterm Infants Receiving Continuous Positive Airway Pressure
Lim K, Wheeler KI, Gale TJ, et al
. 2014 Jan 13
... the optimal oxygen saturation levels for preterm infants have been called "a moving target,"  fluctuating almost as much as our patients' SpO 2 levels. Reaching a consensus on what these levels should be is still a work in progress. Regardless of how those targets are defined, maintaining a baby's oxygen saturation levels within targeted ranges has proved to be a difficult task, one that typically rests on the shoulders of the neonatal intensive care unit (NICU) nurse. Research consistently shows that infants spend significant amounts of time outside of the desired ranges for SpO 2. ...
...Infants who were receiving CPAP with supplemental oxygen were in the target SpO 2 range only 31% (range, 19%-39%) of the total recording time, and most of the total recording time was spent in the hyperoxia range. Within these periods, there were 48 (range, 6.9-90) episodes/24 hours of severe hyperoxia (SpO 2 ≥ 98%), and 9 (range, 1.6-21) episodes/24 hours of severe hypoxia (SpO 2 < 80%). Most high SpO 2 values were in the mildly hyperoxic range. Prolonged (≥ 30 seconds) episodes of serious hypoxia and hyperoxia (in infants receiving supplemental oxygen) were relatively frequent, occurring more often when nurses were taking care of more than 1 patient.
Of note, babies cared for by nurses with fewer than 5 years of experience spent more time in the targeted SpO 2 range than babies cared for by nurses with more experience. Shift (day, evening, or night) had no effect on time spent in the targeted range. Adjustments to FiO 2 were made 25 (range, 16-41) times/24 hours, with a lower frequency during the night shift....