(HealthDay)—Many infants with bronchopulmonary dysplasia (BPD) fail hypoxia challenge testing (HCT) and cannot be deemed fit to fly, according to a study published online Feb. 15 in Pediatrics.

Susanne Vetter-Laracy, Ph.D., M.D., from the University Hospital Son Espases in Palma de Mallorca, Spain, and colleagues determined the earliest fit-to-fly age by testing neonates younger than 1 week in an observational study. The study included three groups: healthy term infants aged ≤7 days (24 infants); preterm infants (≥34 weeks corrected [CGA]; 62 infants) two to three days before discharge; and preterm infants with (BPD; 23 infants). A body plethysmograph with a 15 percent fraction of inspired oxygen was used to conduct HCT.

The researchers found that one term infant (4.2 percent), 12 preterm infants without BPD (19.4 percent), and 16 preterm infants with BPD (69.3 percent) failed HCT (P < 0.001), with a median decrease in oxygen saturation of 16 percent (test fail point was <85 percent). Neither preterm infants without BPD nor term infants had an <85 percent at 39 weeks CGA. Seven of 12 term infants with BPD failed HCT.

"Term and 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," the authors write.