Sweating (sweat contains 0.25% NaCl), breathing, urination, and diarrhea can all lead to loss of body fluids. In cold, high-altitude mountainous areas, due to extremely dry air, sweat evaporates rapidly from the skin surface, and a significant amount of moisture is also expelled through rapid mouth breathing — often without one noticing — resulting in dehydration symptoms (hypertonic dehydration). For illnesses caused by extreme heat or cold as well as acute mountain sickness, maintaining proper fluid intake is an important preventive and therapeutic measure. It not only reduces the risk of illness but also significantly improves overall physiological function.Mountaineeringparticipants experience a considerable enhancement in overall physical performance.
Hypertonic Dehydration
Symptoms: (1) Mild dehydration: thirst. Water loss is 2–4% of body weight.
(2) Moderate dehydration: extreme thirst, fatigue, reduced urination, dark and cloudy urine, dry lips and tongue, restlessness, poor skin elasticity, sunken eye sockets. Water loss is 4–6% of body weight.
(3) Severe dehydration: in addition to the above symptoms, hallucinations, delirium, and even coma may occur. Water loss exceeds 6% of body weight.
Preventive Measures Against Dehydration:
(1) Drink plenty of water. While at the campsite duringactivities,drinking hot tea can both prevent dehydration and provide warmth. Before setting out on a trek, drink a glass of water, and take moderate sips of water (or equivalent beverages) every 30 minutes during the journey. Daily water intake should be >2000 ml/day (during camp activities) to 3000 ml/day (while trekking).
(2) During intense physical activity, do not replace water with high-concentration fruit juice or other highly concentrated fluids (e.g., chocolate drinks, cereal drinks). Recommended beverages: hot water, tea, low-concentration fruit juice drinks, vitamin C effervescent drinks, or other sports drinks.
(3) Also consume some salty nuts or trail snacks to replenish lost body salt.
(4) Carry a 1L–2L insulated bottle during treks.
(5) Water intake must be evenly distributed during the trek, taking full account of return journey hydration needs and emergency situations.
(6) Avoid eating snow or ice to prevent freezing injuries to the mouth and throat. (7) Quit smoking, avoid alcohol, and reduce intake of spicy and high-salt foods.
Treatment for Dehydration:
(1) Drink water. Consider drinking low-concentration glucose water or other sugar-containing hot drinks first. Intravenous fluid replacement may be necessary if needed.
(2) Appropriately supplement salt (oral rehydration salts) and vitamins.
(3) Consume hot liquids (fruit juice drinks, chocolate drinks) or semi-liquids (porridge, cereal, or soft noodles) to restore energy. If the patient’s thirst is alleviated, mood stabilizes, and urination begins, it indicates improvement. Clear consciousness, coherent responses, and clear urine color suggest that dehydration has been corrected.