Gornyashka - Prevention and treatment of acute mountain sickness
It has been proven that AMS develops more often in people who are overweight. Increased physical activity, chronic infection, hypothermia, and lack of training also contribute to the faster development of mountain sickness. Some studies have shown a genetic predisposition to AMS.
The first precursors and symptoms of AMS appear when, under conditions of oxygen deficiency in the body, its organs and systems have not yet had time or are no longer able to maintain a normal supply of tissues with oxygen. In response to hypoxia, which occurs when inhaling air with a reduced partial pressure of oxygen, blood pressure increases in the smallest vessels (capillaries) of the lungs and brain, which promotes the release of blood components from them and the development of edema in the tissue of these organs. There is a point of view that the manifestations of AMS are based on increasing cerebral edema. High-altitude cerebral edema and high-altitude pulmonary edema, representing the final stage of development of AMS, are life-threatening conditions that require immediate descent of the victim and medical intervention.
If signs of AMS develop (headache accompanied by nausea, vomiting, dizziness), it is necessary to stop climbing, and if symptoms are severe, begin to descend down at least 500 m, giving the victim 1 tablet (250 mg) of acetazolamide (diacarb) orally. Here and below, the trade name of the drug is indicated in parentheses, the dose should be twice - every 12 hours. An alternative to the use of acetazolamide for severe AMS is dexamethasone (4 mg orally - 8 tablets or 1 ampoule intramuscularly every 6 hours), a combination of these drugs is possible.
To relieve severe headaches, the use of aspirin (3 doses of 0.5 tablets - 250 mg every 4 hours) or ibuprofen (200-400 mg once) has been proven. In case of repeated vomiting, intramuscular administration of 1 ampoule of metoclopramide (Raglan) is recommended. For sleep disorders, during which blood oxygen saturation may decrease, insomnia, and restless intermittent sleep, zolpidem (ivadal) can be used at a dose of 10 mg. Avoid taking drugs that depress breathing, such as phenazepam, diazepam!
The best prevention of the development of AMS is a gradual climb to altitude and gradual acclimatization. According to existing recommendations, the altitude gain during the day should be no more than 600 m from the place of the last night. For the purpose of drug prophylaxis, the use of the same diacarb (0.5-1 tablet 2 times a day) is indicated, the intake of which must be started 24 hours before the ascent and continued for 2 days after the ascent to altitude. It should be noted that acetazolamide is a diuretic drug, so frequent and copious urination should not be surprising when using it. I would also like to emphasize that taking Diacarb is recommended only in cases where there is a rapid ascent to an altitude of more than 3000 m. To prevent AMS, you can take dexamethasone at a dose of 2 mg every 6 hours according to the above regimen.
Speaking about prevention, we cannot fail to mention vitamins. One of the most important is ascorbic acid (vitamin C), which has antioxidant properties, i.e., it reduces the accumulation of under-oxidized metabolic products that appear during hypoxia. its daily requirement under normal conditions is 70-100 mg, and during acclimatization it is advisable to increase the dose several times. In addition to ascorbic acid, tocopherol (vitamin E) and lipoic acid have antioxidant properties. The study demonstrated the effectiveness of prophylactic administration of these drugs according to the following regimen: vitamin C (500 mg), vitamin E (200 mg) and lipoic acid (300 mg) were given twice a day 3 weeks before ascending to the high altitude zone and during the 10 days of stay at altitude. Participants who took this combination suffered less from altitude sickness and improved digestion.
It is impossible not to mention the very remedy that “we had with us” and which experienced and not so experienced climbers often use to combat the “miner”. Austrian scientists specifically conducted a study: does drinking low doses of alcohol (corresponding to 1 liter of beer) affect the course of AMS. It was found that at an altitude of more than 3000 m, even in small doses, alcohol reduces breathing rate and, as a result, blood oxygen saturation. Therefore, the consumption of alcoholic beverages in the high mountain zone should be prohibited!
High altitude cerebral edema. Signs of increasing cerebral edema are a significant increase in bursting headaches, increased vomiting, the appearance of disturbances in consciousness (the victim becomes lethargic, drowsy, answers questions in monosyllables and not immediately, may be disoriented in the environment) and coordination of movements (shaky, like a drunken gait). In the future, these disorders can intensify until loss of consciousness and the development of coma, in which the victim does not open his eyes in response to painful stimuli. Therefore, at the slightest sign of beginning cerebral edema, the person must be taken down, given oxygen if possible (at a rate of 2-4 liters per minute), and dexamethasone administered intramuscularly (or given orally, if the patient’s condition allows) in an initial dose of 8 mg (2 ampoules or 16 tablets), then given 4 mg (1 ampoule or 8 tablets) every 6 hours.
Currently, dexamethasone is the most effective drug for the treatment of high-altitude cerebral edema. I would like to warn against using furosemide (Lasix) in this situation. It does not reduce cerebral edema either during hypoxia or during traumatic brain injury, and therefore its use in these situations is not recommended.
High altitude pulmonary edema. In severe forms of acute mountain sickness, sometimes suddenly, blood congestion in the pulmonary circulation and pulmonary edema, as well as acute heart failure, may develop. First, shortness of breath appears at rest, bluish discoloration of the nasolabial triangle and lips, hemoptysis, followed by a cough with pink foamy sputum (fluid accumulates in the pulmonary alveoli). the patient tends to take a sitting position, body temperature may rise. The only method to combat pulmonary edema is to immediately descend and inhale oxygen. The victim must be given a semi-sitting position (if he has not taken it on his own), a nitroglycerin tablet must be placed under the tongue, and venous tourniquets must be applied to the thighs so that the pulsation of the arteries can be felt below the place where they are applied. this will create a blood depot in the lower extremities and prevent it from returning to the heart.
Nitroglycerin can be given again after 20 minutes no more than 3 times. 2-3 ampoules of furosemide must be administered intramuscularly. No medicinal manipulation should serve as a delay for going down! Pulmonary edema can very quickly develop against the background of inflammatory diseases of the respiratory tract (tonsillitis, pneumonia), therefore, when signs of these appear, the person must be taken down, while simultaneously providing symptomatic medical assistance.