Doctor warns of altitude risks

POTENTIALLY DEADLY::More than one-quarter of hikers on Jade Mountain show signs of acute mountain sickness, including headaches, dizziness, fatigue and nausea

By Su Chin-feng and Sherry Hsiao  /  Staff reporter, with staff writer

Sat, Aug 17, 2019 - Page 4

Hikers who plan on ascending to high altitudes should consult a doctor about altitude sickness medication before their departure, a family doctor in Taichung said after a 24-year-old college student narrowly escaped death on Hehuanshan (合歡山).

A man surnamed Tsai (蔡) and his friends had planned on summiting their first baiyue (百岳, a mountain higher than 3km above sea level) before graduation, said Wu Han-ming (巫翰明), a physician at Asia University Hospital’s department of family medicine.

Although he exercised regularly, he had not prepared for the altitude change, Wu said.

Midway through the trek, which they were trying to complete quickly, he began experiencing symptoms of altitude sickness, including shortness of breath, headaches, dizziness and malaise, he said.

His friend had luckily gotten a prescription for altitude sickness meditation before the trip and it alleviated his symptoms, saving his life, he said.

Altitude sickness has more to do with personal predisposition than fitness and can be prevented by taking medication one day before hiking, he said.

Travelers should consult a doctor and get a prescription prior to departure, Wu added.

The thin air at higher altitudes is the primary cause of altitude sickness, in addition to the body’s inability to adapt to the rise in elevation, resulting in hypoxemia and then deterioration in the functions of the heart, brain or other parts of the body, the physician said.

The oxygen level at 3km is only about 70 percent of that near sea level, Wu said, adding that the risk is present at 2.1km above sea level or higher.

Many hikers have to be rescued from baiyue due to severe cases of altitude sickness each year, with more than one-quarter of hikers on Jade Mountain (玉山) showing signs of acute mountain sickness (AMS), he said.

Altitude sickness is the third leading cause of non-accidental injury while traveling, behind only the common cold and stomach flu, Wu said, citing a foreign study.

Altitude sickness includes AMS, high-altitude cerebral edema and high-altitude pulmonary edema (HAPE), he said.

The main symptoms of AMS include headaches, dizziness, fatigue, lack of strength, nausea, vomiting, loss of appetite and insomnia, he said.

These symptoms typically emerge six to 12 hours after reaching high altitudes and go away on their own after two to three days as the body adapts to the environment, he said.

In a small number of cases, AMS could worsen into HAPE, with the primary symptom being an unsteady gait, he said, adding that if HAPE is not treated within 24 hours or if the person does not move to a lower altitude immediately, they could die.

Sometimes altitude sickness also causes severe headaches, hallucinations or loss of consciousness, he said.

The earliest signs of HAPE include poor physical performance, shortness of breath, faster heartbeat and dry coughs, he said, adding that resting does not make it easier to breathe, and people with HAPE could also cough up saliva with blood.