Intraocular pressure changes during high-altitude acclimatization.

Mitrofanis Pavlidis; Tobias Stupp; Ilias Georgalas; Evi Georgiadou; Michail Moschos; Solon Thanos

doi:10.1007/s00417-005-1174-1

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Intraocular pressure changes during high-altitude acclimatization.

Mitrofanis Pavlidis·Tobias Stupp·Ilias Georgalas·Evi Georgiadou·Michail Moschos·Solon Thanos

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Abstract

BACKGROUND: To evaluate the relationship between hypobaric hypoxia acclimatization and intraocular pressure (IOP) during ascent, acclimatization, and descent between 2286 m and 5050 m. METHODS: The following acclimatization-indicative physiological parameters were compared daily with IOP changes in eight healthy climbers of the 2003 Greek Karakorum expedition in altitude stages between 500 m and 5050 m: hemoglobin oxygen saturation (PO2), resting heart rate, blood pressure, retinal findings, and the Lake Louise score for acclimatization grading. RESULTS: IOP decreased significantly in the ascent phase (0.58 mmHg/100 m) and recovered (0.71 mmHg/100 m) during acclimatization and descent. A direct proportional correlation between decreases in PO2 and IOP was evaluated. Arterial blood pulse and pressure increased during acclimatization, while IOP decreased. No retinal hemorrhages were observed in well-acclimatized and incompletely acclimatized climbers. CONCLUSIONS: Every new active exposure to hypobaric hypoxia in the ascent phase induced a decrease in the IOP parallel to the PO2 decrease and to the level of acclimatization. The results from our study suggest that IOP changes are related to hypoxia-induced respiratory alkalosis and acclimatization stage, which could be used as a simple mobile screening test for acclimatization level to reveal acute mountain sickness and its severe consequences.

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Acclimatization Adult Aged Alkalosis, Respiratory Altitude Altitude Sickness Atmospheric Pressure Blood Pressure Female Heart Rate Humans Hypoxia Intraocular Pressure Male Middle Aged Partial Pressure Journal Article

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Mitrofanis Pavlidis, Tobias Stupp, Ilias Georgalas, Evi Georgiadou, Michail Moschos, Solon Thanos. 2005-08-13. Intraocular pressure changes during high-altitude acclimatization.. https://doi.org/10.1007/s00417-005-1174-1

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