AltitudeOmics: impaired pulmonary gas exchange efficiency and blunted ventilatory acclimatization in humans with patent foramen ovale after 16 days at 5,260 m

作者：Elliott Jonathan E; Laurie Steven S; Kern Julia P; Beasley Kara M; Goodman Randall D; Kayser Bengt; Subudhi Andrew W; Roach Robert C; Lovering Andrew T^*

来源：Journal of Applied Physiology, 2015, 118(9): 1100-1112.

DOI：10.1152/japplphysiol.00879.2014

• shunt
• high altitude
• acute mountain sickness

A patent foramen ovale (PFO), present in similar to 40% of the general population, is a potential source of right-to-left shunt that can impair pulmonary gas exchange efficiency [i.e., increase the alveolar-to-arterial PO2 difference (A-aDO(2))]. Prior studies investigating human acclimatization to high-altitude with A-aDO(2) as a key parameter have not investigated differences between subjects with (PFO+) or without a PFO (PFO-). We hypothesized that in PFO+ subjects A-aDO(2) would not improve (i.e., decrease) after acclimatization to high altitude compared with PFO- subjects. Twenty-one (11 PFO+) healthy sea-level residents were studied at rest and during cycle ergometer exercise at the highest iso-workload achieved at sea level (SL), after acute transport to 5,260 m (ALT1), and again at 5,260 m after 16 days of high-altitude acclimatization (ALT16). In contrast to PFO- subjects, PFO+ subjects had 1) no improvement in A-aDO(2) at rest and during exercise at ALT16 compared with ALT1, 2) no significant increase in resting alveolar ventilation, or alveolar PO2, at ALT16 compared with ALT1, and consequently had 3) an increased arterial PCO2 and decreased arterial PO2 and arterial O-2 saturation at rest at ALT16. Furthermore, PFO+ subjects had an increased incidence of acute mountain sickness (AMS) at ALT1 concomitant with significantly lower peripheral O-2 saturation (SpO(2)). These data suggest that PFO+ subjects have increased susceptibility to AMS when not taking prophylactic treatments, that right-to-left shunt through a PFO impairs pulmonary gas exchange efficiency even after acclimatization to high altitude, and that PFO+ subjects have blunted ventilatory acclimatization after 16 days at altitude compared with PFO- subjects.

• 出版日期2015-5-1