Figures
- FIGURE 1
Susceptibility-weighted magnetic resonance imaging in a) axial and b) sagittal planes shows microhaemorrhages (arrows) in the corpus callosum of a 65-year-old female who had suffered from severe high-altitude cerebral oedema 7 weeks previously at 3450 m. Reproduced from [1] with permission from the publisher.
- FIGURE 2
a) Chest radiograph of a 37-year-old male mountaineer with high-altitude pulmonary oedema (HAPE) showing a patchy to confluent distribution of oedema, predominantly on the right side; b) computed axial tomography scan of 27-year-old mountaineer with recurrent HAPE showing patchy bilateral nodular distribution of oedema. Reproduced from [61] with permission from the publisher.
- FIGURE 3
Individual bronchoalveolar lavage a) red blood cell counts and b) albumin concentrations plotted against pulmonary artery systolic pressures at high altitude (4559 m). Reproduced from [56] with permission from the publisher.
Tables
- TABLE 1
Arterial blood gas analysis at 4559 m
Subjects PaO2 mmHg PaCO2 mmHg PA–aO2 mmHg No AMS 14 39.6±4.5 30.0±3.6 7.9±3.7 Mild AMS 19 37.6±4.3 30.7±4.0 9.3±4.3 Moderate–severe AMS 10 33.9±4.0* 31.1±2.8 12.5±4.5* HAPE 4 23.2±3.3*** 28.4±3.5 26.0±2.9*** Analysis of arterial blood obtained from a femoral artery a few hours after arrival at the Margherita hut (Monte Rosa, Italy) in subjects with no acute mountain sickness (AMS), mild AMS (score 2–3 points according to Hackett et al. [103]), moderate-to-severe AMS (>3 points) or high-altitude pulmonary oedema (HAPE) (verified using chest radiography). PaO2: arterial oxygen tension; PaCO2: arterial carbon dioxide tension; PA–aO2: alveolar–arterial oxygen tension difference. *: p<0.05, compared with mild and no AMS; ***: p<0.001, compared with all groups. Data from [32].
- TABLE 2
Medications for the prevention and treatment of acute altitude illness
Dosage for prevention Dosage for treatment AMS Acetazolamide 125 or 250 mg every 12 h 250 mg every 12 h Dexamethasone 2 mg every 6 h or
4 mg every 12 hAMS: 4 mg every 6 h
HACE: 8 mg once then 4 mg every 6 hHAPE Nifedipine 30 mg sustained release version every 12 h 30 mg sustained release version every 12 h Tadalafil# 10 mg every 12 h 10 mg every 12 h Salmeterol¶ 125 μg inhaled every 12 h Not used for treatment AMS: acute mountain sickness; HAPE: high-altitude pulmonary oedema; HACE: high-altitude cerebral oedema. #: should not be used in conjunction with nifedipine; ¶: should not be used as the sole agent for prevention.
- TABLE 3
Risk assessment for acute altitude illness
Planned ascent profile and prior history at high altitude# Low risk Ascent ≤500 m·day−1 above 2500 m
Ascent >500 m·day−1 above 2500 m in persons with exposure to high altitude <3000 m in preceding weeks
No history of AMS, HACE or HAPE with similar ascent profileModerate risk Unknown susceptibility to AMS, HACE or HAPE and planned ascent >500 m·day−1 above 3000 m
Unknown susceptibility to acute altitude illness and planned ascent to >3000 m in 1 dayHigh risk Unknown susceptibility to AMS, HACE or HAPE and planned very rapid ascent (>>500 m·day−1) to final altitude >4000 m
History of AMS, HACE and HAPE with previous exposure similar to the planned ascentAMS: acute mountain sickness; HACE: high-altitude cerebral oedema; HAPE: high-altitude pulmonary oedema. #: altitudes refer to the individual's sleeping elevation.
