Soldiers deployed at high altitudes have to brave serious health hazards, some of which are fatal. Here is a list of high-altitude ailments that specialists in the Defence Institute of Physiology and Allied Sciences (DIPAS), Delhi, have detailed:
Acute Mountain Sickness: At heights over 9,000 feet, there's every chance of suffering an initial bout of sickness before acclimatisation. For the first five days - and sometimes longer - one goes through excruciating headaches, nausea, vomiting, loss of appetite, sleep distraction and depression.
Hypoxia: Rarefied air starved of oxygen coupled with biting cold causes stress and limits physical and mental functioning. Hyperventilation or hard breathing is the body's way of trying to cope with the lack of oxygen. The psychological stress manifests itself in feelings of isolation, monotony, fear of the unknown, sensory deprivation and severe depression for being away from family and friends.
High-Altitude Pulmonary Edema (HAPE): Low atmospheric oxygen results in fluid collecting in the lungs. This acts as a further barrier for the absorption of oxygen, which can lead to asphyxiation. However, DIPAS specialists say they have discovered that a combination of nitric oxide with oxygen is a good curative. This reduces pressure in the arteries and improves ventilation. If HAPE is acute, the only way out is to evacuate and bring the patient down to lower heights.
Cold injuries: Most high-altitude injuries are to do with frostbite. In subzero temperatures, touching a cold mug with bare hands can be like contact with a scalding-hot kettle. Water getting into a shoe can spell gradual numbness that a soldier pays little heed to but which ends in pain. This could also involve amputation. Chilblains is also common leading to swelling of feet and hands in extreme temperatures.
High-Altitude Cerebral Edema: HAPE pales before this. It is certainly fatal.
