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according to chengdu seventh people's hospital:do not do strenuous exercise after entering the plateau, do adaptive exercises, and adhere to the principle of step-by-step elevation. when you first enter the plateau, you should immediately reduce the amount and intensity of labor, and gradually increase it after adaptation. if you have symptoms such as dizziness, headache, fatigue, dyspnea, dry cough, cyanosis, tachycardia, etc. and they gradually worsen, you should rest in bed and go to the nearest hospital for diagnosis and treatment in time.

why do people experience altitude sickness when they go to tibet?

please keep this expert guide

the qinghai-tibet plateau is known as the "roof of the world". it is the highest plateau in the world and the largest inland plateau in my country, with an average altitude of more than 4,000 meters. every tourist season, a large number of tourists flock to the plateau, eager to experience the wonders of the plateau. however, everyone has a knot in their hearts: will i have altitude sickness when i come to the qinghai-tibet plateau? what is altitude sickness like?

what is altitude sickness?

altitude sickness, also known as altitude sickness, is a manifestation of the human body's unique physiological state after entering a high altitude area and being exposed to the high altitude environment.the various discomforts that occur when the human body rapidly enters a plateau area above 3,000 meters above sea level are actually a type of altitude sickness.

everyone who enters a high altitude plateau will experience altitude sickness, which can be divided into acute altitude sickness and chronic altitude sickness according to the length of stay at the plateau. acute altitude sickness can be divided into acute mild altitude sickness, high altitude cerebral edema, and high altitude pulmonary edema according to the severity of the reaction. chronic altitude sickness can be divided into high altitude polycythemia, high altitude hypertension, high altitude heart disease, and high altitude depression.

most of the altitude sickness that occurs after entering the plateau is acute mild altitude sickness. as the stay on the plateau increases, most people will feel relieved, and the symptoms of some people will disappear completely. there is no need to worry too much. what we need to pay attention to are the more serious altitude sickness that may occur, such as high-altitude pulmonary edema and high-altitude cerebral edema.

why does altitude sickness occur?

first of all, we need to understand the definition of plateau and the division of altitude. in geography, areas with an altitude of more than 500 meters are called plateaus. there are five regions divided by height: the area with an altitude of 500-1500 meters is low altitude, the area with an altitude of 1500-2500 meters is moderate altitude, the area with an altitude of 2500-4500 meters is high altitude, the area with an altitude of 4500-5500 meters is extra high altitude, and the altitude of more than 5500 meters is extremely high altitude. the volume percentage of various gases that make up the atmosphere remains constant from sea level to the troposphere, but the atmospheric pressure decreases with increasing altitude. the partial pressures of various gases that make up the atmospheric pressure also decrease with increasing altitude. as a result, the atmospheric oxygen partial pressure also decreases with increasing altitude.

as the altitude continues to rise, the oxygen partial pressure continues to decrease. within a certain range, the human body has a compensatory mechanism that can adapt to this decrease in oxygen partial pressure, with no discomfort or mild discomfort. when the oxygen partial pressure drops to a certain level, the decrease in oxygen partial pressure has a greater impact on the gas exchange in the human lungs, the transport of oxygen in the blood, and the diffusion of tissue oxygen, which will cause hypoxia in the body and cause various discomforts in our body. at this time, altitude sickness will occur. the degree of discomfort of this reaction is determined by the altitude of the plateau that is quickly entered. usually at an altitude of 2500-4500 meters, most people who enter this area will experience symptoms such as increased breathing and heart rate, headache, decreased appetite, insomnia, and a decrease in blood oxygen saturation to varying degrees, thus causing altitude sickness.

when we enter extremely high altitudes (4500-5500 meters), due to the thin oxygen, people's hypoxia is more obvious, and the oxygen saturation may be less than 60%. exercise can cause severe hypoxemia, and severe hypoxemia is also prone to occur during sleep at night. when people enter extremely high altitude areas (over 5500 meters), the oxygen saturation is usually less than 50%, and serious physiological and metabolic disorders may occur due to the body's decompensation, which is life-threatening. usually, only trained expedition climbers carrying additional oxygen will enter this area.

so you will not experience altitude sickness as long as you enter the plateau. you must reach a certain altitude to experience altitude sickness. the average altitude of the qinghai-tibet plateau is above 4,000 meters. people who first come to the qinghai-tibet plateau are prone to altitude sickness.

what are the specific manifestations?

headache is one of the most common symptoms of altitude sickness, which usually occurs within a few hours after entering the plateau and can last for several days to a week. headache may be accompanied by symptoms such as nausea and vomiting. due to the thin oxygen, patients with altitude sickness may experience symptoms such as difficulty breathing and shortness of breath, which may be more obvious during activities.

patients with altitude sickness may also experience symptoms such as palpitations and accelerated heartbeats, which are a sign that the body is increasing its heart rate to adapt to the hypoxic environment. some patients may also experience symptoms such as loss of appetite and indigestion, which may be related to the weakening of gastrointestinal function caused by hypoxia. altitude sickness can also cause insomnia and poor sleep quality, which are related to the increased excitability of the central nervous system caused by hypoxia.

in addition, patients with altitude sickness may also experience symptoms such as fatigue, dizziness, inattention, and memory loss. our blood pressure will also fluctuate after entering the plateau. usually, systolic and diastolic blood pressure will increase immediately, and generally reach a steady state in 1 to 2 months. long-term residence in the plateau may also cause a drop in blood pressure. both systolic and diastolic blood pressure may decrease, and the change in systolic blood pressure is more obvious. living in plateau areas for a long time, in response to hypoxia, the body will compensatory erythrocyte proliferation, red blood cells and hemoglobin increase by 10% to 20%, and increase oxygen delivery capacity. however, hemoglobin should not exceed 180g/l. too many red blood cells can lead to high-altitude polycythemia.

increased heart rate, deep and rapid breathing, and slightly increased blood pressure are all acute mild altitude sickness, mainly caused by hypoxia. most people can alleviate and disappear after a short period of acclimatization or symptomatic treatment, so there is no need to worry too much. symptoms persist and worsen, with resting dyspnea, chest tightness, cough, pink foamy sputum, oliguria, confusion, cyanosis, and wet rales in both lungs. severe headache accompanied by vomiting, mental confusion, ataxia, auditory hallucinations, visual hallucinations, speech and disorientation. as the disease progresses, there may even be unsteady gait, drowsiness, stupor or coma, and some may even have convulsions. severe altitude sickness, such as acute pulmonary edema and acute cerebral edema, are fatal and severe altitude sickness. when they occur, you must lie still immediately, inhale high-flow oxygen, seek medical attention in time, and immediately retreat to a low-altitude area if conditions permit, to avoid a sharp deterioration of the disease and endanger your life.

how to prevent altitude sickness?

before entering the plateau, knowing the characteristics of the plateau environment, common sense of life, and knowledge of altitude sickness prevention and treatment will help overcome tension, fear, and anxiety. a comprehensive physical examination should be conducted before entering the plateau. people with organic diseases, severe neurasthenia, or respiratory infections should not enter the plateau. at the same time, we must adjust our mentality to ensure that the body is in good condition.

when entering the plateau, you can adopt the principle of step-by-step ascent. if you cannot ascend step by step, you can take acetazolamide and/or dexamethasone preventively to prevent severe altitude sickness.

after entering the plateau, we need to control the pace of life, reduce the amount of work and labor intensity, reduce oxygen consumption, and gradually increase the amount of work after adaptation. if conditions permit, oxygen should be inhaled as much as possible. the recommended oxygen concentration is 2l/min, including in sleep state, to maintain oxygenation above 90%. we also need to prepare finger oximeters and blood pressure monitors to monitor blood oxygen saturation and blood pressure regularly.

the daily temperature difference on the plateau is large, so you should pay attention to keep warm and avoid respiratory infections. the plateau climate is dry, so you should drink more water to ensure the body's water supply and prevent dehydration. we should eat a reasonable diet, avoid spicy food, have a balanced diet, and avoid large fluctuations in weight. at the same time, we should avoid smoking and drinking and maintain good living habits. people with insomnia on the plateau can take tranquilizers to improve their sleep quality.

we should be fully prepared for the trip to the plateau, understand the altitude, climate characteristics and eating habits of the tourist destination in advance, avoid staying in high-altitude areas for a long time, and prepare portable oxygen cylinders if conditions permit during the trip, in case of emergency. such oxygen cylinders can be rented at large tourist distribution points. due to the vast area and sparse population of the qinghai-tibet plateau, medical resources are unevenly distributed. in addition to carrying sufficient amounts of their own commonly used medicines, tourists should also carry commonly used medicines with them, such as ibuprofen and acetaminophen for headaches, tranquilizers for sleep assistance, acetazolamide and (or) dexamethasone and nifedipine tablets for the prevention and treatment of pulmonary edema, berberine and montmorillonite powder for the treatment of diarrhea, etc.

finally, i would like to remind everyone that self-driving tours in the plateau are extremely attractive to everyone who yearns for plateau travel, but the traffic conditions in the plateau are complex, the environment along the way is very different, and the altitude span is extremely large. it not only requires excellent driving skills, good vehicle condition, and sufficient guarantees, but also needs to face the challenge of plateau hypoxia. ordinary tourists should not try it easily. once altitude sickness occurs during self-driving, improper handling may endanger life. although the scenery of the plateau is gorgeous, life is the most precious.

source: kankan news