Effect of a smaller target range on the compliance in targeting and distribution of oxygen saturation in preterm infants

BACKGROUND: Following recent recommendations, the oxygen saturation (SpO2) target range for preterm infants in our nursery was narrowed towards the higher end from 85%-95% to 90%-95%. We determined the effect of narrowing the SpO2 target range on the compliance in target range and distribution of SpO2 in preterm infants.

METHODS: Before and after changing the target range from 85%-95% to 90%-95%, infants <30 weeks of gestation receiving oxygen were compared during their admission on the neonatal intensive care unit. For each infant, distribution of SpO2 was noted by collecting SpO2 samples each minute, and the percentage of time spent with SpO2 within 90%-95% was calculated. Oxygen was manually adjusted. Hypoxaemic events (SpO2 <80%) where oxygen was titrated were analysed.

RESULTS: Data were analysed for 104 infants (57 before and 47 after the range was narrowed). The narrower range was associated with an increase in the median (IQR) SpO2 (93% (91%-96%) vs 94% (92%-97%), p=0.01), but no increase in median time SpO2 within 90%-95% (49.2% (39.6%-59.7%) vs (46.9% (27.1%-57.9%), p=0.72). The distribution of SpO2 shifted to the right with a significant decrease in SpO2 <90%, but not <80%. The count of minute values for Sp02 <80% decreased, while the frequency and duration of hypoxaemic events and oxygen titration were not different.

CONCLUSION: Narrowing the target range from 85%-95% to 90%-95% in preterm infants was associated with an increase in median SpO2 and a rightward shift in the distribution, but no change in time spent between 90% and 95%.