Apnoea-triggered increase in fraction of inspired oxygen in preterm infants: a randomised cross-over study

Abstract

ObjectivesTo investigate the impact of a pre-emptive apnoea triggered oxygen response on oxygen saturation (SpO2) targeting following central apnoea in preterm infants.DesignInterventional crossover study of a 12-hour period of automated oxygen control with an apnoea response (AR) module, nested within a crossover study of a 24-hour period of automated oxygen control compared with aggregated data from two flanking 12-hour periods of manual control.SettingNeonatal intensive care unitPatientsPreterm infants receiving non-invasive respiratory support and supplemental oxygen; median (IQR) birth gestation 27 (26–28) weeks, postnatal age 17 (12–23) days.InterventionAutomated oxygen titration with an automated control algorithm modified to include an AR module. Alterations to inspired oxygen concentration (FiO2) were actuated by a motorised blender. Desired SpO2range was 90–94%. Apnoea detection was by capsule pneumography.Main outcome measuresDuration, magnitude and area under the curve (AUC) of SpO2deviations following apnoea; frequency and duration of apnoeic events. Comparisons between periods of manual, automated and automated control with AR module.ResultsIn 60 studies in 35 infants, inclusion of the AR module significantly reduced AUC for SpO2deviations below baseline compared with both automated and manual control (manual: 87.1%±107.6% s, automated: 84.6%±102.8% s, AR module: 79.4%±102.7% s). However, there was a coincident increase in SpO2overshoot (AUC (SpO2>SpO2(onset)); manual: 44.3±99.9% s, automated: 54.7%±103.4% s, AR module: 65.7%±126.2% s).ConclusionAutomated control with a pre-emptive apnoea-triggered FiO2boost resulted in a modest reduction in post-apnoea hypoxaemia, but was followed by a greater SpO2overshoot.Trial registration numberACTRN12616000300471.