Hypoxia Challenge Testing in Neonates for Fitness to Fly

BACKGROUND: Preflight hypoxia challenge testing (HCT) in a body plethysmograph has previously been done only on infants > 3 months of corrected gestational age (CGA). This study aims to determine the earliest fit-to-fly age by testing neonates < 1 week old. METHODS: A prospective observational study was carried out on 3 groups of infants: healthy term infants <= 7 days old, preterm infants (>= 34 weeks CGA) 2 to 3 days before discharge, and preterm infants with bronchopulmonary dysplasia (BPD). HCT was conducted using a body plethysmograph with a 15% fraction of inspired oxygen. The oxygen saturation (SpO(2)) test fail point was < 85%. RESULTS: Twenty-four term (mean CGA 40 weeks), 62 preterm (37 weeks), and 23 preterm with BPD (39.5 weeks) infants were tested. One term infant (4.2%) and 12 preterm infants without BPD (19.4%) failed. Sixteen (69.3%) preterm infants with BPD failed (P < .001), with a median drop in SpO(2) of 16%. At 39 weeks CGA, neither preterm infants without BPD nor term infants had an SpO(2) < 85%. However, 7 of 12 term infants with BPD failed the HCT. CONCLUSIONS: Term and preterm infants without BPD born at > 39 weeks CGA do not appear to be likely to desaturate during a preflight HCT and so can be deemed fit to fly according to current British Thoracic Society Guidelines.