Introduction: There is little data available to determine the normal response to normobaric hypoxia inhalation testing (NHIT) and air travel. Quantifying a healthy response may assist in the evaluation of passengers considered at risk for air travel. The aims of this study were: 1) to quantify the degree of desaturation in healthy subjects during a NHIT and air travel; and 2) assess the validity of the NHIT when compared with actual in-flight responses. Methods: There were 15 healthy adults (age 23-57; 10 women) who volunteered for this study. Preflight tests included lung function, arterial blood gas, pulse oximetry (SpO2), and NHIT (inspired oxygen 15%). SpO2 and cabin pressure were measured continuously on each subject during a commercial air flight (mean cabin altitude 2178 m; range 1719-2426 m). In-flight oxygenation was compared with the preflight NHIT. Results: Lung function testing results were normal. There was significant desaturation (SpO2) during the NHIT (pre: 98 ± 2%; post: 92 ± 2%) and at cruising altitude (pre: 97 ± 1%; cruise: 92 ± 2%). There was no difference between the final NHIT SpO2 and the mean in-flight SpO2. There was a significant difference between the lowest in-flight SpO2 (88 ± 2%) vs. the lowest NHIT SpO2 (90 ± 2%). Discussion: Oxygen saturation decreases significantly during air travel in normal individuals. In this group of healthy passengers the NHIT approximates some, but not all, aspects of in-flight oxygenation. These results can be used to describe a normal response to the NHIT and air-travel.
|Number of pages||5|
|Journal||Aviation Space and Environmental Medicine|
|Publication status||Published - Nov 2006|