Prolonged automatic oxygen support in preterm infants

Rationale: Preterm infants often require supplemental oxygen to prevent hypoxemia, a condition that has been associated with organ damage and an increased mortality. However, too much oxygen supplementation resulting in hyperoxemia may lead to systemic oxidative damage and long-term complications such as retinopathy of prematurity (ROP). For these reasons, oxygen saturation is continuously measured in preterm infants with pulse oximetry (SpO2) aiming to keep it within a safe target range (TR) by manually titrating the fraction of inspired oxygen (FiO2). However, studies in preterm infants have shown that SpO2 targeting is a clinical challenge with patients spending only 50% of the time within their SpO2 TR, due to clinical instability and the limited time nurses have to adjust the amount of oxygen. Newly developed techniques incorporated in the ventilator provide the opportunity of automated FiO2 control (A-FiO2). Only short term studies (days) have investigated the A-FiO2 function and long term effects need to be evaluated. The short term studies indicate that this closed-loop A-FiO2 reduces time outside the TR, decreases number and duration of hypo- and hyperoxemic episodes, and reduces caregivers’ workload compared to manual FiO2 control (M-FiO2).

Objective: To assess the effectiveness of continuous, long term (weeks) use of a closed-loop FiO2 control system in comparison with M-FiO2 control in preterm infants with non-invasive respiratory support.

Study design: Randomised controlled trial.

Study population: Preterm infants treated in a level III NICU.

Intervention: In order to study the effectiveness over a longer period of time of the A-FiO2 function of the ventilator, preterm infants will be set at random to either continuous use of the A-FiO2 function or to continuous use of M-FiO2 control from first week of life till the 28th day of life.

Preterm infants often require supplemental oxygen to prevent hypoxemia and hyperoxemia. Conditions that have been associated with organ damage and an increased mortality. Newly developed techniques incorporated in the ventilator provide the opportunity of automated FiO2 control (A-FiO2). The hypotheses of this trial are based on the need to assess the effectiveness of A-FiO2 adjustments over time. The primary outcome variable is therefore defined as the proportion of time for both control settings with SpO2 within the assigned saturation range (87-95%), measured over a time period of maximum 28 days and excluding time with SpO2 above the range while FiO2 is set at 0.21.

Not applicable

Infants enrolled in the study will randomly be assigned to either the A-FiO2 function when receiving non-invasive respiratory support from the ventilator with closed-loop or to the routine M-FiO2 function by the nurses when receiving non-invasive respiratory support. Duration of the intervention per patient will be from randomization to 28 days of age.