453 - Percentage of Time in SpO2 Target Range in Extremely Preterm Infants Changes From Birth to 36 Weeks Postmenstrual Age

Poster Number: 453
Publication Number: 453.228

Zenaida R. Tauscher, Peyton Manning Children's Hospital at St. Vincent, Indianapolis, IN, United States; Kelsey A. Montgomery, Peyton Manning Children's Hospital at St. Vincent, Indianapolis, IN, United States; Sibil Gil, Peyton Manning Children's Hospital at St. Vincent, Indianapolis, IN, United States; Markus K. Tauscher, Peyton Manning Children's Hospital at St. Vincent, Indianapolis, IN, United States

Background: Extremely preterm infants require ventilatory support and supplemental oxygen to keep SpO2 in a specific target range. Research showed that these infants stay within target range between 16-64% of the time.

Objective: Determine how the % of time with SpO2 in target range for preterm infants born < 29 wks gestational age (GA) changes from the first week after birth (Wk1) until 36 wks postmenstrual age (PMA) and assess the impact of GA at birth, PMA and respiratory support on this percentage.

Design/Methods: This prospective longitudinal, observational cohort study included eligible infants admitted to the Peyton Manning Children’s Hospital NICU between 12/2019 and 01/2021. Infants were divided into 3 GA groups: 22-24, 25-26 and 27-28 wks. The percentage of a 24-hr period an infant spent in, below and above the SpO2 target range was documented daily from a bedside pulse oximeter. Recordings during Wk1 were compared to recordings on day of life (DOL) 28 and at 36 wks PMA. Mode of respiratory support was also documented.

Results: 402 24-hr period recordings from 64 infants were included. The median % of time in SpO2 target range decreased from 44.8 in Wk1 to 24.4 at DOL28 (p < 0.05) to 11.4 at 36 wks PMA (p < 0.05) for all GA groups. In contrast, % of time above target range increased from 49.3 to 69.5 (p=0.07) to 86 (p < 0.05). Median % of time below target range decreased from 5.3 to 5 (p=0.11) to 2.8 (p < 0.05). Although % of time below target range in 25-26 wk infants decreased from 8.9 to 4.6 at 36 wks (p=0.05), it first increased to 21.5 at DOL28 (p < 0.05). In 27-28 wk infants, % of time below target range did not change significantly from Wk1 to 36 wks. % of time in target range was highest (61.5) in infants receiving invasive respiratory support during Wk1 and decreased to 43.2 at DOL28 (p < 0.05). % of time below target range increased to 26.2 on DOL28 from 14 in Wk1 (p < 0.05). In infants receiving noninvasive respiratory support, % time in and above target range did not change but % time below target range increased from 1.6 in Wk1 to 3.8 on DOL28 (p < 0.05) and 4.6 at 36 wks (p < 0.05).Conclusion(s): For all infants, time in target range decreased from birth to 36 wks, while time above target range increased. Time below target range decreased by 36 wks for all infants except those born between 27-28 wks. Time below target range increased for infants 25-26 wks and for infants on invasive or noninvasive respiratory support from Wk1 to DOL28. Our results show that % of time in SpO2 target range is dynamic and depends on various factors including GA at birth, PMA and mode of respiratory support.
Table 1. Maternal and neonatal data
Figure 1. Median percentage of time above, in and below SpO2 target range for all infants and for different gestational age groups