Table 3. Nocturnal polygraphic monitoring.
| Controls (n = 10) | HAPE-group (n = 8) | ||||
| 4559 m, night 1 | 4559 m, night 2 | 490 m, baseline | 4559 m, night 1 | 4559 m, last night | |
| Recording time, min | 472±12 | 437±65 | 446±20 | 438±89 | 367±138 |
| Mean nocturnal SpO2, % | 73±3 | 73±3 | 95±1 | 62±8* ¶ | 60±8* ¶ |
| Breath rate, 1/min | 19.7±2.8 | 20.0±2.6 | 17.2±1.4 | 25.8±5.6* ¶ | 27.0±4.8* ¶ |
| Tidal volume, L | 0.28±0.06 | 0.25±0.06 | 0.22±0.07 | 0.30±0.13 | 0.32±0.14 |
| Ventilation, L/min | 5.6±1.4 | 5.1±1.8 | 3.8±1.4 | 7.6±1.7* ¶ | 8.6±3.1* ¶ |
| Mean inspiratory flow, L/sec | 0.21±0.05 | 0.19±0.06 | 0.16±0.05 | 0.29±0.08* ¶ | 0.33±0.01* ¶ |
| %Time in Periodic Breathing | 35±30 | 30±29 | 0±0 | 56±20* | 52±20* |
| Apnea/hypopnea index, 1/h | 58±50 | 48±44 | 2±2 | 101±40* | 97±45* ¶ |
| Oxygen desaturation index, dips >3%/h | 37±29 | 35±32 | 1±1 | 66±34* | 59±35* |
| Heart rate, 1/min | 81±10 | 79±10 | 59±7 | 90±11* | 94±9* ¶ |
Means±SD; 490 m refers to the baseline examinations in Zurich performed in HAPE susceptibles exclusively; night 1 corresponds to the 1st measurement, last night to the last measurement before overt HAPE occurred in the HAPE group and to the measurement in the 2nd night at 4559 m in controls respectively.
*
P<0.05 vs. 490 m within group.
¶
P<0.05 vs. controls.