Automated control of oxygen titration in preterm infants on non-invasive respiratory support

Objective: To evaluate the performance of a rapidly responsive adaptive algorithm (VDL1.1) for automated oxygen control in preterm infants with respiratory insufficiency.

Design: Interventional cross-over study of a 24-hour period of automated oxygen control compared with aggregated data from two flanking periods of manual control (12 hours each).

Setting: Neonatal intensive care unit.

Participants: Preterm infants receiving non-invasive respiratory support and supplemental oxygen; median birth gestation 27 weeks (IQR 26-28) and postnatal age 17 (12-23) days.

Intervention: Automated oxygen titration with the VDL1.1 algorithm, with the incoming SpO₂ signal derived from a standard oximetry probe, and the computed inspired oxygen concentration (FiO₂) adjustments actuated by a motorised blender. The desired SpO₂ range was 90%-94%, with bedside clinicians able to make corrective manual FiO₂ adjustments at all times.

Main outcome measures: Target range (TR) time (SpO₂ 90%-94% or 90%-100% if in air), periods of SpO₂ deviation, number of manual FiO₂ adjustments and oxygen requirement were compared between automated and manual control periods.

Results: In 60 cross-over studies in 35 infants, automated oxygen titration resulted in greater TR time (manual 58 (51-64)% vs automated 81 (72-85)%, p<0.001), less time at both extremes of oxygenation and considerably fewer prolonged hypoxaemic and hyperoxaemic episodes. The algorithm functioned effectively in every infant. Manual FiO₂ adjustments were infrequent during automated control (0.11 adjustments/hour), and oxygen requirements were similar (manual 28 (25-32)% and automated 26 (24-32)%, p=0.13).

Conclusion: The VDL1.1 algorithm was safe and effective in SpO₂ targeting in preterm infants on non-invasive respiratory support. Trial registration number: ACTRN12616000300471.