This study was done with the purpose to evaluate the pulmonary and nasal functions, including nasal cytology, in healthy volunteers moving for 1 week from an altitude of 2000 m to another of 3400 m.

PNIF, pulmonary function, including PEF, MCTt, nasal cytology, and oxygen saturation were studied on 5 different occasions—T1: at base camp; T2: at the mountain refuge; T3: after 7 days at 3400 m; T4: after the return at the base camp; and T5: at the base camp after 15 days.

With respect to T1, PEF values decreased at T2, T3, T4, and T5. Forced expiratory volume in the first second and forced vital capacity did not differ among the 5 different times of measurements. In regard to T1, PNIF values increased at T2 and T3. MCTt and O2 sat showed similar but opposite changes with MCTt increased at T2 and T3 with respect to T1, while O2 sat decreased at T2 and T3 with respect to T1. At nasal cytology, the number of neutrophils increased at T2 with respect to T1. PNIF changed with altitude from T1 to T4 even accounting for the effect of all the other variables.

The study concluded data seem to support the utility of MCTt for studying nasal mucosa damage induced by the high altitude.

Reference: https://journals.sagepub.com/doi/pdf/10.1177/1945892420916393