Assessment of portable oxygen concentrators to revert induced hypoxia by hypoxic challenge testing in paediatric patients. A comparative study between continuous flow and pulse flow delivery systems

Abstract

Introduction: Commercial aircrafts at cruising altitude are pressurized to a cabin altitude of 2438 m (≙ FiO2 0.15). To evaluate hypoxic inflight risk Hypoxic Challenge Testing (HCT) is recommend whereby oxygen requirements can be titrated. Portable oxygen concentrators (POCs) are approved for onboard use but there is lack of evidence about the use especially in children. Pulse flow POCs are designed for adults and therefore not recommended in paediatric age. We tested the effectiveness and safety of POCs during HCT. Material and Methods: Prospective interventional crossover study. N=26 infants (mean gestational age 30.4 weeks) who underwent HCT. Tested POCs: SeQal-Eclipse3® continuous flow and InogenOne® pulse flow. In case of Sat.O2 ≤ 85 %, oxygen was administered through POC. Results: 22 ex-preterm patients were included (4 dropped out). Both POCs achieved immediate reversal of hypoxia in all cases without associating adverse events. No significant difference was observed between preterm patients +/- bronchopulmonary dysplasia concerning hypoxic recovery. Discussion: We present the results of a pilot study evaluating POCs effectiveness to revert hypoxia induced by HCT in children. Previous studies tested POCs in adults (mountain, hypobaric chamber) where all tested POCs achieved sufficient oxygen output. Our study also demonstrates that POCs are able to sense patient inspiration even in preterm babies. We conclude that POCs generate sufficient oxygen to revert HCT induced hypoxia and should be considered as a valid delivery method for inflight oxygen supply.