One important aspect of planning your hiking journey in the Himalayas is the (higher) altitude. As we go higher above the sea level the oxygen level drops (e.g. 50% at 5000m). It takes time for the human body and brain to adjust to this oxygen deprived environment. If we go up to quickly we can get altitude sickness (AMS) which if not taken care properly can be deadly.
Altitude is something that most of us do not bother about as most of us live in the plains or below 2500m altitude. As we go above 3000m however we need to give sufficient time to our body to “Acclimatize”. General rule of thumb says do not increase more than 500m per day above 3000m. This means that if we plan for a 5000m pass crossing we should give at least 5 days (3000, 3500, 4000, 4500, 5000m) time if the hikers are not yet prior acclimatized.
Prevention
Altitude sickness is something that is specific from person to person. Some individuals are more vulnerable to it, others can endure it much better. A simple preventive way is to carry an oximeter which clips onto your finger and shows the oxygen saturation in your blood (SpO2). When properly acclimatized it’s around 80-90%. If it drops below 70 then you should take it easy – stop climbing up further. If it drops below 60 then it’s getting more drastic and you should reduce altitude as soon as possible.
Another good way to acclimatize the body sooner is to climb up to higher altitudes and descent again to lower altitude for night stay. Similar climbing up to a high altitude pass and descending to a lower altitude campsite on the other side is better then say staying overnight at the pass.
Assignment
Proper acclimatization is of utmost importance in planning your journey / timeline allowing the body to adapt properly to higher altitudes. Ignoring so can lead to serious illness and death.
