Exerted pressure by an in-flight oxygen mask.

BACKGROUND

F-16 pilots wear an in-flight oxygen mask to prevent hypoxemia. In the contact area with the mask, the pilots experience nasal discomfort and pain, and may even develop nasal deformities. A likely cause is the pressure exerted by the mask. In this study the hypothesis was that the change in pressure exerted on the nose would be higher than on the chin, an area free of symptoms.

METHODS

Six F-16 pilots and five healthy former F-16 pilots volunteered to participate in this observational pilot study. At baseline the pilots donned mask and helmet. The median delta pressure (deltap) recordings at baseline were compared to the exerted deltap during the experimental head movements.

RESULTS

At baseline, there was no significant difference between the median deltap on the nose and chin (2 vs. 1.6 mmHg, T = 2). Head movements increased the median deltap on the nose by 50 mmHg (T = 0) and on the chin by 31 mmHg (T = 0) when compared to baseline. Head movements also decreased the pressure by -20 mmHg (T = 1.75) on the nose and -11 mmHg (T = 0) on the chin.

CONCLUSIONS

The data show that the baseline deltap is higher on the nose than on the chin. The head movements both increased and decreased the exerted pressure on the nose and the chin. These observations suggest that further evaluation of the effect of flight conditions on the exerted pressure is worthwhile to understand its contribution to the nasal symptoms.