Effect of the Target Range on Arterial Oxygen Saturation Stability in Extremely Premature Infants

Abstract

<b><i>Objective:</i></b> The aim of this study was to compare the effect of targeting arterial oxygen saturation (SpO₂) in the high (93–95%) versus the low portion (90–92%) of the recommended range of 90–95% on oxygenation stability in extremely premature infants. <b><i>Methods:</i></b> Premature infants of ≤28 weeks of gestational age who received a fraction of inspired oxygen (FiO₂) &#x3e; 0.21 after day 14 were eligible. FiO₂ was adjusted by a dedicated investigator to keep SpO₂ between 90–92% and 93–95% for 2 h each in random sequence. Episodes of intermittent hypoxemia (IH) were defined as SpO₂ &#x3c;90% for ≥10 s; severe IH episodes were defined as SpO₂ &#x3c;80% for ≥10 s. Hyperoxemia was defined as SpO₂ &#x3e;95% or &#x3e;98%. <b><i>Results:</i></b> Eighteen premature infants were enrolled. Their (mean ± SD) GA was 26 ± 1.5 w. Seven infants were on mechanical ventilation, 4 infants on nasal ventilation, and 7 infants on nasal cannula. They were on a mean FiO₂ 0.38 ± 0.12 at study entry. Episodes of IH and severe IH were more frequent during the low compared to the high target (36.6 [27.0–41.3] vs. 16.0 [7.8–19.0], <i>p</i> &#x3c; 0.001; 8.4 ± 9.3 vs. 3.2 ± 4.3, <i>p</i> = 0.002). The proportions of time with SpO₂ &#x3e;95% and &#x3e;98% were greater with the high target (13.9 ± 11 vs. 34.1 ± 15.4%, <i>p</i> &#x3c; 0.001; 0.9 [0–5.7] vs. 3.4 [0.5–16.1]%, <i>p</i> = 0.002). <b><i>Conclusion:</i></b> In this group of extremely premature infants, targeting SpO₂ at the lower portion of the recommended range resulted in more frequent episodes of IH. However, targeting the higher SpO₂ range led to more hyperoxemia. This trade-off warrants further investigation.