| Altitude (m) | Subjects, n (men) | ONSD (mm)* mean (SD) | AMS score, mean (SD) | Resting HR (beats/min), mean (SD) | Oxygen saturations (%), mean (SD) |
| 0 | 13 (10) | 4.69 (0.46) | 0 (0) | 57 (5) | 97.0 (0) |
| 2000 | 13 (10) | 4.89 (0.68) | 0.6 (1.4) | 70 (11) | 95.4 (1.1) |
| 3700 | 12 (9) | 4.91 (0.48) | 1.6 (1.1) | 77 (11) | 87.6 (2.5) |
| 5200 | 13 (10) | 5.20 (0.66) | 2.8 (1.3) | 89 (20) | 74.8 (8.3) |
| 6400 | 10 (9) | 5.31 (0.75) | 2.6 (1.9) | 96 (10) | 71.3 (6.4) |
AMS, acute mountain sickness; HR, heart rate; ICP, intracranial pressure; ONSD, optic nerve sheath diameter.
*ONSD mean of right and left eyes for the sample.