The hypoxia challenge test does not accurately predict hypoxia in flight in ex-preterm neonates

Chest. 2008 May;133(5):1161-6. doi: 10.1378/chest.07-2375. Epub 2008 Jan 15.


Background: Air travel may pose risks to ex-preterm neonates due to the low oxygen environment encountered during flights. We aimed to study the utility of the preflight hypoxia challenge test (HCT) to detect in-flight hypoxia in such infants.

Methods: Ex-preterm (gestation < or = 35 completed weeks) infants ready for air transfer from the intensive/special care nursery to regional hospitals were studied. A pretransfer HCT was performed by exposing infants to 14% oxygen for 20 min. Failure was defined as a sustained fall in pulse oxygen saturation (Spo(2)) < or = 85%. A nurse blinded to the test result monitored the in-flight oxygen saturations in each infant. If Spo(2) fell to < or = 85%, oxygen was administered.

Results: Forty-six infants with median gestation of 32.2 weeks (range, 24 to 35.6 weeks) and birth weight of 1,667 g (range, 655 to 2,815 g) were recruited. No infants were receiving supplemental oxygen at the time of transfer. The HCT was performed at a median corrected age of 35.8 weeks (range, 33.1 to 43 weeks). Thirty-five infants (76%) passed the test, and the remainder failed. During the flight, 16 infants met the criteria for in-flight oxygen, but 12 of these infants (75%) had passed the preflight HCT. Of the 11 infants who failed the HCT, only 4 infants (36%) required in-flight oxygen. The HCT incorrectly predicted in-flight responses in 42% (19 of 46 infants).

Conclusions: A significant percentage of ex-preterm neonates require in-flight oxygen supplementation. The HCT is not accurate for identifying which infants are at risk for in-flight hypoxia.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aerospace Medicine*
  • Altitude
  • Female
  • Follow-Up Studies
  • Gestational Age
  • Humans
  • Hypoxia / diagnosis*
  • Hypoxia / physiopathology
  • Hypoxia / prevention & control
  • Infant, Newborn
  • Infant, Premature / physiology*
  • Infant, Premature, Diseases / diagnosis*
  • Infant, Premature, Diseases / physiopathology
  • Lung Diseases / diagnosis*
  • Lung Diseases / physiopathology
  • Male
  • Oxygen Inhalation Therapy
  • ROC Curve
  • Respiratory Function Tests
  • Retrospective Studies
  • Travel*