Bloated bovines Altitude sickness is also the scourge of entirely different population of mountain-dwellers: cows. By the time a rancher spots one lumbering up and down the mountain, its swollen chest sloshing between its front legs, there is not much he can do except move the animal to a lower altitude and hope it lives.
Every summer in the U. West—when ranchers take cattle to graze on grassy mountain slopes—tens of thousands of cows die because they cannot adapt to the thin, oxygen-poor air. For the past two years, scientists collaborating with a new research facility at New Mexico State University N.
Once they find the genes, the idea is to breed them out of the bovine population. From May to November each year, ranchers in many parts of the western U. In the Rockies, summer pastures range from 1, to 3, meters; an altitude greater than 1, meters is enough to induce brisket disease. In some parts of Montana and Colorado, cattle graze at altitudes upward of 4, meters, says Manny Encinias , director of N.
Whereas some cows take the swift transition to high altitudes in stride, others swell up and die. Not all breeds are equally susceptible, nor are all individuals from a single breed—just as human susceptibility to acute mountain sickness varies. Healthy cows respond to low-oxygen environments in a characteristic way: their hearts beat faster to deliver enough oxygenated blood to the body and brain, and blood vessels in the lung constrict to shunt blood to the organ's oxygen-rich areas.
Cows that develop brisket disease respond similarly, but their body's compensation is too aggressive for their own good. Blood pressure increases so much that plasma seeps out of the blood vessels into tissues surrounding the heart and lungs, bloating the cows' chests.
And blood vessels in the lung constrict so much that the blood backs up into the heart, which eventually gives out. The cows collapse and die from heart failure. At Top of the Valle, which is nearly 2, meters above sea level, researchers are working to pinpoint the exact genes responsible for the physiological differences between a cow that keels over in the mountains and one that remains as lively as Julie Andrews in the Alps.
If tests suggest the cow won't fare well in the mountains, a rancher may avoid a potential loss by selling the cow to a lower-altitude ranch. Some ranchers have considered giving cattle drugs designed to treat mountain sickness in people, like acetazolamide , but the FDA has not approved the use of such drugs in animals meant for human consumption.
Even if N. Symptoms of altitude sickness The initial symptoms of altitude sickness can include: Headache Lethargy A drop in performance Lack of coordination Insomnia Appetite loss Dizziness Nausea Vomiting. Severe altitude sickness There are two main types of severe altitude sickness: high altitude pulmonary oedema fluid within the lungs and high altitude cerebral oedema fluid within the brain.
Symptoms of severe altitude sickness include: Breathlessness Heart palpitations Blue-tinged skin and nails due to lack of oxygen cyanosis Frequent coughing because of fluid in the lungs Sputum may be frothy or tinged pink with blood from the damaged lung tissue Irrational behaviour, such as refusing to acknowledge symptoms Inability to sit up or walk in a straight line.
Prevention of altitude sickness The best way to prevent altitude sickness is to ascend slowly. Other suggestions for preventing altitude sickness include: See your doctor for information and advice before your trip.
Some climbers believe that switching to a high-carbohydrate diet before they go trekking helps to reduce the risks. Be prepared. Pack all necessary first aid items, including medications. Considerable evidence exists for the effectiveness of acetazolamide as a preventative. It is particularly useful if you are flying into a location at altitude and will not have time to adjust. Salmeterol inhalers and even Viagra-like drugs have been used to prevent fluid building up in the lungs.
Remember that medications such as nifedipine and dexamethasone are best used as a treatment for mild altitude sickness, not as a prevention measure. These medications could mask the early warning signs. Only climb with experienced guides. Increase your fluid intake. You may need up to seven litres every day. Avoid cigarettes and alcohol. Sleeping tablets must not be used, as they can lead to an increase in hypoxia due to their central nervous system depressing action. Be aware that you are at increased risk of altitude sickness if you have experienced it before.
First aid for altitude sickness Use the 'buddy system', because you will most likely refuse to acknowledge your own symptoms of altitude sickness. If one of your party is showing the signs of altitude sickness, first aid suggestions include: Don't climb any higher. Camp and wait until the symptoms subside. This can take a couple of days. Symptoms of altitude sickness Symptoms of altitude sickness usually develop between 6 and 24 hours after reaching altitudes more than 2,m above sea level.
Symptoms are similar to those of a bad hangover and include: headache feeling and being sick dizziness tiredness loss of appetite shortness of breath The symptoms are usually worse at night.
Preventing altitude sickness The best way to prevent getting altitude sickness is to travel to altitudes above 2,m slowly. It usually takes a few days for your body to get used to a change in altitude. You should also: avoid flying directly to areas of high altitude, if possible take 2 to 3 days to get used to high altitudes before going above 2,m avoid climbing more than m to m a day have a rest day every m to m you go up, or rest every 3 to 4 days make sure you're drinking enough water avoid smoking and alcohol avoid strenuous exercise for the first 24 hours eat a light but high-calorie diet Medicines Consider travelling with these medicines for altitude sickness: acetazolamide to prevent and treat high-altitude sickness ibuprofen and paracetamol for headaches anti-sickness medicine, such as promethazine , for nausea In the UK, acetazolamide is not licensed to treat altitude sickness.
Promethazine is available from pharmacies. You do not need a prescription to buy it. Treating altitude sickness If you think you have altitude sickness: stop and rest where you are do not go any higher for at least 24 to 48 hours if you have a headache, take ibuprofen or paracetamol if you feel sick, take an anti-sickness medicine, such as promethazine make sure you're drinking enough water do not smoke, drink alcohol, or exercise Acetazolamide can be used to reduce the severity of your symptoms, but it will not completely get rid of them.
You can continue going up with care once you feel you have fully recovered. If you do not feel any better after 24 hours, go down by at least m about 1, feet.
Do not attempt to climb again until your symptoms have completely disappeared. See a doctor if your symptoms do not improve or get worse. Early symptoms include:. If you have these symptoms, stop, rest, and drink water. You may need to go back down to a lower altitude until your symptoms go away. If you have these symptoms, go to a lower altitude right away and get medical help. Symptoms that are ignored or left untreated can be life threatening.
High-altitude illness most often occurs at altitudes higher than 8, feet. Everyone is at risk for high-altitude illness. Children and older adults are at an increased risk because it takes their bodies longer to adjust. You also may be at a greater risk if you:. People who have symptoms of high-altitude illness should see a doctor. Be sure to tell him or her about the conditions you were in when you had the symptoms. Your doctor will do a physical exam. Based on the severity of your symptoms, he or she may order tests.
Tests may include a chest X-ray, brain scan, or electrocardiogram ECG. These help diagnose the type of illness and decide on a treatment plan.
The first thing you should do is to safely go down to a lower altitude right away. If your symptoms are mild, you may be able to stay at that altitude and let your body adjust. Rest and drink water until you feel better. It may help to use a device that provides extra oxygen. If needed, your doctor may prescribe medicine to prevent or treat symptoms. One example is acetazolamide. When taking this medicine, drink a lot of water and avoid alcohol. You will need medical treatment.
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