A team of Swiss researchers has come up with a novel solution to help prevent altitude sickness, a potentially lethal medical condition for climbers.
They studied a specific form of altitude sickness known as high-altitude pulmonary edema, which is characterised by fluids accumulating in the lungs, interfering with the flow of oxygen and carbon dioxide. This can be fatal at high altitude.
The study showed that some people could not evacuate sodium properly from their lungs and therefore have the same problem with fluids. People, who have suffered from pulmonary edemas, are particularly susceptible.
The researchers tried salmeterol - an asthma drug known to help evacuate sodium from the lungs of animals - on climbers who had suffered from altitude sickness. It is usually distributed with a spray inhalator.
"This has been used for years to treat people suffering from asthma," said Urs Scherrer, one of the researchers from Lausanne University hospital involved in the study. "But this was the first time it was used to try and clear sodium out of people's lungs."
Thirty-seven climbers took part in the test, with 18 of them receiving the drug and the 19 others a placebo. They were then sent up into the mountains shortly after being treated, and the majority of those who received the salmeterol showed no evidence of pulmonary edema.
There was some risk involved in sending the climbers back up the mountains, but the researchers took all the necessary precautions according to Scherrer.
"We've already carried out this type of experiment before at high altitude, and we made sure we had everything on hand to treat them if something did occur," he told swissinfo.
Keen to climb
The researcher said that climbers who had suffered from pulmonary edemas often wanted to head back up the mountains. "If they take part in this type of study, it's quite a safe way for them to see if it will happen to them again."
He added that the climbers had just as much interest as the scientists in finding new ways of treating altitude sickness.
However Scherrer warned that climbers should not simply take the asthma drug as a preventative measure. The researchers believe that some rules should always apply when climbing at higher altitudes.
"People shouldn't climb too quickly," said Scherrer. "They should take the time to acclimatise slowly, especially if they have suffered from altitude sickness, to avoid taking too many risks. This can only be a supportive treatment."
Despite this, the Lausanne scientists feel confident their research is an advance in the treatment of altitude sickness.
"This asthma drug is a reasonable alternative to others that been used for the last 10 years to treat pulmonary edemas," Scherrer told swissinfo.
by Scott Capper