TO successfully complete a high-altitude hikeand-fly adventure preparation is key. Technically, ‘high altitude’ is between 8,000ft (2,439m) and 12,000ft (3,657m) ASL with ‘very high altitude’ between 12,000-18,000ft (5,486m). ‘Extreme altitude’ is everything above 18,000ft. Above 26,250ft (8,000m) mountaineers also talk about the ‘Death Zone’, where there is insufficient oxygen to support human life for an extended period of time.
Once the body reaches about 6,900ft (2,100m), the saturation of oxyhaemoglobin in the blood begins to decrease rapidly and the body needs to adjust to the altitude to allow it to partially compensate for the lack of oxygen. This process takes time and can’t be forced. Altitude affects people uniquely; it is impossible to predict how altitude will affect individuals although in general, young fit males seem to be the worst…