Safety and Security
HIGH ALTITUDE SICKNESS INFORMATION
Physical Training for trekking and Expedition
As surprising as it may seem, elite athletes are not necessarily the most successful. Many trained athletes have failed when they tried to climb or walk too fast in high altitude.
Being athletic (for example a marathon runner) may help you in high altitude conditions, but this is not enough. In the mountain you need patience, perseverance, mental toughness and good luck. The cardinal rule is to respect acclimatization steps. High altitude climbing requires good cardio-pulmonary capacity, good endurance and proper acclimatization. So you have to train well in advance preferably long distance effort (several day long hikes, biking..) Don’t leave out interval training because it increases your VO2max capacity. A good VO2 max will help you deal with inevitable strong efforts.
Acute mountain sickness (AMS)
To understand this phenomenon, it is necessary to recall the two parameters that characterize altitude, Air pressure decreases and oxygen becomes less available. The body does not respond well to these conditions and although it is capable of adapting by increasing ventilation and the number red blood of cells, it needs time to acclimatize.
High altitude Pulmonary Edema (HAPE)
It is one of the main complications of acute mountain sickness. It usually occurs near beginning of a period spent at altitude, during acclimatization. Those ignore the stages of acclimatization are the first effected. Those who have previously suffered from acute pulmonary edema are at a high risk of recurrence.
Beware, edema develops during the night because breathing rate is reduced and it is at sunrise when the effects of HAPE become evident. From 4000m never sleep alone.
Certain sign and symptoms indicate edema and permit its detection before it is too late.
- Headaches do not subside despite large doses of aspirin or paracitamol.
- Fatigue is at its greatest and when a person cannot catch his breath, even at rest, this causes alarm.
- some behavioural disorders can be associates with HAPE such as excessive sleepiness, laziness or alternatively, restlessness with fever.
- If no one has detected this warning signs, the persons soon stars to asphyxiate and laryngeal cracking noise coming from the back of his throat can become audible
- When the sputum produced during coughing resembles a kind of salmon mouse, the conditions becomes life-threatening and the case an emergency
High altitude cerebral edema (HACE)
Like pulmonary edema, this dreaded complication of AMS generally occurs near beginning of a stay at altitude, during acclimatization. People who have previously suffered from acute high altitude pulmonary edema or high altitude cerebral are more likely to be effected. People who do not respect acclimatization stage are first to succumb. Beware, like pulmonary edema, it is during the night that the condition develops and at dawn when it kills. It can, therefore, never be repeated often enough that one should not sleep alone above 4000m.
Caution, cerebral edema can be associated with pulmonary edema; abnormal behavior accompanying pulmonary edema may actually be attributable to cerebral edema.
Like pulmonary edema, cerebral edema is a poorly treated acute mountains sickness:
Again, headaches do not subside despite high doses of aspirin or paracitamol
Tiredness is severe and the most wworrying signs are balance problems and abnormal behavior: the subject is no longer coherent, is delirious, suffers from hallucinations and becomes addressives or very drowsy.
Cerebral edema slightly less common than pulmonary edema, is often more difficult to treat because the patient is not always co-operative.
HACE is more insidious than HAPE because it sometimes occurs without an evident prodromal period.
Without treatment the patient sinks into a coma. This is an extreme emergency since the situation becomes life threatening.
ACTION TO BE TAKEN IN THE EVENT OF HACE
- Urgent descent is the best treatment
- Oxygen if available
- Recompression chamber if available