Health issues which might develop at high altitude to hikers, skiers, and soldiers
Editorial by neucrad health February 9, 2019
Altitude has a substantial impact on human physiology as there is a considerable decrease in the level of oxygen after climbing above 2100 metres or 7000 feet above sea level. At this condition, human beings experience a significant reduction in oxygen saturation of haemoglobin (concentration of oxygen in erythrocytes) which leads to an adverse effect on human health. There are reports of both short-term and long-term medical issues due to staying in high altitude for a longer duration. Brave soldiers of India and other parts of the world often compromise their health guarding high-altitude frontiers.
How Oxygen Concentration Differs with Altitude?
The concentration of oxygen is maximum at sea-level at 20.9 per cent; it decreases exponentially with the increase of altitude. Human beings can best accustom themselves at the sea-level where the concentration of oxygen saturates their haemoglobin. At the height of 5000 metres above sea-level, the level of oxygen becomes half of its value at sea-level. Human body starts acclimatising itself with the increase in altitude and drop in oxygen concentration. However, after a specific value, it becomes challenging to adapt to nature, health issues may crop up at this stage. Scientists often tag altitude above 8000 metres or 26000 feet as “death zone” since it is nearly impossible to sustain life at this dangerous height.
Health Issues which might Develop at High Altitude
There are three principal medical issues which may develop when human beings start living at high altitudes for an extended period.
∙ Acute Mountain Sickness
∙ High-Altitude Cerebral Edema (HACE)
∙ High-Altitude Pulmonary Edema (HAPE)
Let us look at these conditions in detail.
Acute Mountain Sickness
Acute mountain sickness is usually seen in hikers, skiers, and soldiers when they quickly ascend to high altitude (above 2400 metres), and the body does not get enough time to acclimatising itself. It can be mild as well as severe, and in most cases, conditions reverse at prompt medical intervention. Low level of oxygen and atmospheric pressure are the principal causal factors behind this medical issue.
Symptoms of Acute Mountain Sickness
Symptoms of acute mountain sickness are sub-divided under two categories mild acute mountain sickness and severe acute mountain sickness.
In case of mild acute mountain sickness, individuals may experience dizziness, muscle aches, headache, nausea, vomiting, loss of appetite, swelling in the face, hands, and feet, shortness of breath, and rapid heartbeat. These symptoms usually manifest within hours of ascending to extreme height.
Sometimes, people may also undergo severe acute mountain sickness where their muscles, heart, lungs, and nervous system gets affected. Common symptoms include chest congestion, discolouration of the skin, inability to walk, loss of body balance, and social withdrawal. Anaemic patients or those having a history of lung diseases are prone to severe acute mountain sickness.
Treatment of Acute Mountain Sickness
Treatment of acute mountain sickness depends on the severity of symptoms, In most of the instances, medications for blood pressure, headache relief, correction of breathing problems, and use of lung inhalers alleviate the medical issue. However, in extreme cases, hospitalisations may also be necessary.
High-Altitude Cerebral Edema (HACE)
HACE is another high-altitude medical issue where individuals experience swelling in the brain, or build-up of fluid within this organ as a result of the sudden climb to upper altitude or prolonged stay in extremely high altitudes. In most of the cases, it is vasogenic oedema occurring due to breaking down of endothelial barrier between blood and brain. However, instances of cytotoxic oedema have also been reported. Individuals may prevent the occurrence of HACE by slow ascend giving enough time to the body to acclimatise. Once, HACE gets detected in patients, they should immediately descend to a lower altitude, or it may result in coma or death. Untreated HACE may become fatal within 48 hours.
High-Altitude Pulmonary Edema (HAPE)
HAPE is also a severe high-altitude health issue where fluid accumulation occurs within the lungs. It usually happens at the height of 4900 to 8200 feet above sea level. It is a primary cause of death among mountaineers, soldiers, and hikers. Common symptoms include chest tightness, blue colouration of the skin, rapid heart rate, and extreme body weakness. Increase in pulmonary artery pressure or increase in the permeability of the vascular endothelium is often the probable cause of HAPE. Immediate medical intervention, administering oxygen, and descend to lower altitude saves a life in this situation.
These were some of the high-altitude health issues which hikers, skiers, and soldiers may experience due to sudden climb to extreme heights or prolonged stay at such altitudes.
Reference: en.wikipedia.org, healthline.com, familydoctor.org
