Randomised cross-over study of automated oxygen control for preterm infants receiving nasal high flow

Abstract

Objective To evaluate a prototype automated controller (IntellO 2 ) of the inspired fraction of oxygen (FiO 2 ) in maintaining a target range of oxygen saturation (SpO 2 ) in preterm babies receiving nasal high flow (HF) via the Vapotherm Precision Flow. Design Prospective two-centre order-randomised cross-over study. Setting Neonatal intensive care units. Patients Preterm infants receiving HF with FiO 2 ≥25%. Intervention Automated versus manual control of FiO 2 to maintain a target SpO 2 range of 90%–95% (or 90%–100% if FiO 2 =21%). Main outcome measures The primary outcome measure was per cent of time spent within target SpO 2 range. Secondary outcomes included the overall proportion and durations of SpO 2 within specified hyperoxic and hypoxic ranges and the number of in-range episodes per hour. Results Data were analysed from 30 preterm infants with median (IQR) gestation at birth of 26 (24–27) weeks, study age of 29 (18–53) days and study weight 1080 (959–1443) g. The target SpO 2 range was achieved 80% of the time on automated (IntellO 2 ) control (IQR 70%–87%) compared with 49% under manual control (IQR 40%–57%; p<0.0001). There were fewer episodes of SpO 2 below 80% lasting at least 60 s under automated control (0 (IQR 0–1.25)) compared with manual control (5 (IQR 2.75–14)). There were no differences in the number of episodes per hour of SpO 2 above 98% (4.5 (IQR 1.8–8.5) vs 5.5 (IQR 1.9–14); p=0.572) between the study arms. Conclusions The IntellO 2 automated oxygen controller maintained patients in the target SpO 2 range significantly better than manual adjustments in preterm babies receiving HF. Trial registration number NCT02074774 .