Effects of a new device for automated closed loop control of inspired oxygen concentration on fluctuations of arterial and different regional organ tissue oxygen saturations in preterm infants.

OBJECTIVE

To assess the efficacy of a newly developed system for closed loop control of the fraction of inspired oxygen (FiO) on variation of arterial (SpO) and on regional tissue oxygen saturation (StO) in preterm infants with fluctuations in SpO.

DESIGN

Randomised crossover trial comparing automated (auto) to manual FiO adjustment (manual) during two consecutive 24 hours periods using a Sophie infant ventilator (SPOC).

SETTING

Tertiary university medical centre.

PATIENTS

Twelve very low birthweight infant (VLBWI) (gestational age (median; IQR): (25; 23-26 weeks); birth weight (mean±SD): (667±134 g); postnatal age (mean±SD): (31.5±14 days)).

MAIN OUTCOME MEASURE

Time within SpO target range.

RESULTS

There was an increase in time within the intended SpO target range (88%-96%) during auto as compared with manual mode (77.8%±7.1% vs 68.5%±7.7% (mean±SD), p<0.001) and a decrease in time below the SpO target during the auto period (18.1%±6.4% vs 25.6%±7.6%; p<0.01). There was a dramatic reduction in events with an SpO <88% with >180 s duration: (2 (0-10) vs 10 (0-37) events, p<0.001) and the need for manual adjustments. The time the infants spent above the intended arterial oxygen range (4.1%±3.8% vs 5.9%±3.6%), median FiO, mean SpO over time and StO in the brain, liver and kidney did not differ significantly between the two periods.

CONCLUSIONS

Closed-loop FiO using SPOC significantly increased time of arterial SpO within the intended range in VLBWI and decreased the need for manual adjustments when compared with the routine adjustment by staff members. StO was not significantly affected by the mode of oxygen control.