Desaturations with or without Bradycardia Are Associated with Cerebral and Abdominal Hypoxemia: Secondary Analysis of a Randomized Clinical Trial.

Abstract

Introduction: The aim of this study was to determine if episodes of desaturation, either with or without bradycardia, are associated with cerebral and abdominal hypoxemia in preterm infants.

Methods: Secondary analysis of a single-center pilot randomized clinical trial including preterm infants <29 weeks of gestation on positive pressure respiratory support. Rates of cerebral hypoxemia (<55% for ≥10 s) and abdominal hypoxemia (<40% for ≥10 s) on near-infrared spectroscopy corresponding with episodes of desaturation (oxygen saturations <85% for ≥10 s) either with or without bradycardia (<100 bpm for ≥10 s) were compared using a generalized estimating equation to address repeated events from the same subject.

Results: Twenty-five infants with a gestational age (mean + SD) of 24 weeks 6 days ± 11 days and birth weight 645 ± 142 grams were included. Desaturations with and without bradycardia were both associated with cerebral hypoxemia and abdominal hypoxemia (all p < 0.05). Cerebral hypoxemia was more strongly associated with desaturations with bradycardia compared to episodes without bradycardia (adjusted odds ratio [aOR], 95% confidence intervals [CI]: 0.34, 0.25-0.47; p < 0.001). There were also more episodes of abdominal hypoxemia during desaturations with bradycardia versus desaturations with no bradycardia (aOR, 95% CI: 0.35, 0.26-0.46; p < 0.001). The rate of concurrent cerebral and abdominal hypoxemia was also higher during desaturations with bradycardia.

Discussion: Desaturations, whether occurring with or without bradycardia, are associated with cerebral and abdominal hypoxemia in very preterm infants. Cerebral and abdominal hypoxemia are more likely during episodes of desaturation with bradycardia than during episodes without bradycardia.

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