Headaches, nausea, difficulty sleeping, and laboured breathing are just a few of the symptoms Nia Lewis experienced during a research trip in The Himalayas last year. But physical discomfort aside, the 27-year-old UBC Okanagan researcher says the trip was a welcome break from her usual office-bound work.
Professor Philip Ainslie, was lead investigator on a planned 12 to 15 experiments for which the researchers would double as subjects.
“You can sit at a desk and read textbooks and journal articles to learn what happens in the body,” says the post-doctoral fellow, who was in Nepal to study the effects of oxygen deprivation on blood flow through the brain and vital organs, “but [being at high altitude] was a different learning experience because I actually physically felt the changes and I knew what was happening and why. It was a good learning tool for me.”
Lewis was one of 25 international researchers who trekked up Mount Everest to the Ev-K2-CNR Pyramid Laboratory, located at an altitude of 5,050 metres. Her UBC supervisor, Professor Philip Ainslie, was lead investigator on a planned 12 to 15 experiments for which the researchers would double as subjects. Some of the studies also involved local people, in a ground-breaking attempt to look at how humans born at altitude adapt to oxygen deprivation.
Ainslie is Canada Research Chair in Cerebrovascular Function in Health and Disease and is based in the School of Health and Exercise Sciences. This was his seventh trip to the Himalayas, and he has built up a network of local people who contribute to the research. He calls this trip an example of “high-risk, high-reward science” – the costs reached about $200,000, and several PhD and post-doc projects hung in the balance. “Every time things evolve because you have better technology and better people to work with,” he says. “So this was the pinnacle in terms of more advanced equipment and more aggressive experiments.”
They all travelled to Kelowna in the early months of 2012 for baseline testing, and met up again at the end of April in Kathmandu.
The symptoms that Lewis and her colleagues developed at high altitudes were not seriously threatening, but are similar to those experienced by people suffering from sleep apnea, chronic heart and respiratory illnesses, and strokes. The scientists hope to adapt their experiment results for further clinical studies with the goal of devising new methods of prevention and treatment. Some studies also looked at the causes of sleep apnea, a condition that routinely affects both visitors and high-altitude residents.
Members of the research team came from universities in the US, New Zealand, Australia, the UK and the Netherlands. They all travelled to Kelowna in the early months of 2012 for baseline testing, and met up again at the end of April in Kathmandu, where they spent six days. Because of the amount of lab equipment they brought on their flights, their personal luggage was limited, and they spent time buying generators, medical supplies, drugs, hiking boots and clothing. Lewis had never travelled to a developing nation before. “It was a bit of an eye-opener,” she says. “The rubbish on the side of the road, in the river, chickens on the roof of cars, and the bartering. They’ll begin with a price four times what it’s worth. I wasn’t very good at that.”
The group then flew from Kathmandu to Lukla. The short runway heads uphill straight towards the mountain. Old and unregulated aircraft and unpredictable weather make it one of the unsafest flights in the world. “Basically you just hope for the best,” says Lewis, recalling the landing. “It’s a sheer drop. We were pretty nervous.”
They frequently crossed small narrow bridges, which bounced and swung hundreds of metres above valleys.
Lukla is at 2,860 metres, and from there they began their trek. They had about 20 Sherpas and 15 yaks carrying all their equipment. After six hours of walking, they stayed at a teahouse. The accommodations were typically heated with a fire, which was also used for cooking, and yak dung served as fuel. “So it stinks and it’s quite smoky,” says Lewis, acknowledging the threat of respiratory disease for people constantly breathing in the smoke. Everywhere they stayed, the researchers were met with hospitality. The Nepalese standard diet is rice and lentils, but they would offer guests a variety of foods: porridge or muesli at breakfast, pasta or rice for lunch.
The higher the group climbed on the eight-day trek, the harder it became. The terrain started out as lush, green and tropical, and quickly became very rocky. They frequently crossed small narrow bridges, which bounced and swung hundreds of metres above valleys. Lewis was feeling short of breath, but fortunate not to have the stomach problems others experienced.
At two towns on the way, two PhD students used a vascular ultrasound to scan the vessels in subjects’ necks and measure the blood flow. Throughout the trek, they took medications to help reduce Acute Mountain Sickness, but had to stop once they arrived at the lab so the drugs didn’t interfere with the studies. Some developed chest colds or infections from inhaling the dust along the path. The team included two medical doctors, who helped administer medications.
Lewis found the last day of the trek the most difficult. “We started at 4,000 metres, and it was a big climb and very rocky. You’re kind of concentrating on where you’re stepping and it’s loose gravel, and I fell down quite a few times. It was a few steps, stop, catch your breath,” she recalls. She kept an eye on her heart rate monitor, which reached 170 beats per minute. “My maximum heart rate would be approximately 190, so I was working pretty hard. At times I was, like, ‘I just want to get there now!’”
The Pyramid Laboratory is located more than halfway up the Khumbu Valley near Mount Everest base camp. It is surrounded by stunning mountains and glaciers, and daytime temperatures hover around zero. A brick building nearby was the sleeping quarters. But once they arrived, there was no time to rest or enjoy the scenery. Lewis was research coordinator, managing the complex logistics of many studies over their three-week stay. The laboratory had solar panels for all electricity and heat, and there was sometimes Internet access, but the remote location presented several challenges. Their blood gas analyzer machine, (which gives various measurements including oxygen and carbon dioxide in blood) froze, so they put it in a room used as a sauna to defrost it. Far worse, one undergraduate developed appendicitis and had to be flown by helicopter to a hospital in Kathmandu.
One of the studies examined the causes of sleep apnea, a condition in which a person slows or stops breathing during sleep. Lewis and her colleagues would take their turns sleeping in the Pyramid, which was not heated, covered in wires hooked up to research equipment. The disorder, which Lewis experienced at altitude, also added to her daily fatigue. “We had our sleeping bags and extra blankets, but you could see your breath,” she says, with her tendency to downplay discomfort. “But we all eventually fell to sleep.”
Her own study looked at how stiff vessels become at high altitude. She is now comparing her colleagues’ results with those taken from the participating local people. “Our blood vessels get a lot stiffer at high altitude,” she says, “so we become more like the Sherpas, which was quite a cool finding. I’m not sure what this means yet. The body adapts very quickly and whether this change that I’ve seen is a positive or a negative finding is for future work.”
Lewis found the trip down the mountain much easier than going up, although harder on the knees. “You can just feel a difference in the air and you can feel it’s less challenging,” she says. “It’s quite strange, we were all high off oxygen.” One more complication was that planes weren’t flying from Lukla to Kathmandu due to the weather. Ainslie was able to find helicopters to take them instead.
“Our blood vessels get a lot stiffer at high altitude,” she says, “so we become more like the Sherpas, which was quite a cool finding.”
Some of the studies – such as a seven-hour process involving sampling blood from the subject’s vessels going to and from the brain, followed by a maximum exercise test – were physically taxing. But Ainslie was very pleased with the outcomes. “It was entirely successful in that normally we plan 12 to 15 experiments, hoping that even if half of them work out we get some great data. On this trip everything worked out.”
Families of Sherpas that he has known for a decade participated in several studies, and members of the team trained one 28-year-old guide called Nema to help collect data. The researchers developed friendships with many of the locals and maintained bonds through Facebook. One study tested children born at altitude but now living in Kathmandu, to see how lack of oxygen affects the development of the lungs and heart. Ainslie has planned another research trip, and hopes also to bring Nepalese subjects to Canada to test them at sea level. “The downside to commercialism in all these countries is that Sherpas [are leaving their high‑altitude homes] because they make more money working in construction in Japan,” he says. “So I really think that if we don’t do these experiments in the next decade then we’ll lose the opportunity to look at natural selection and adaptation at high altitude.”
Fully recovering from the trip took Lewis three months. She felt disoriented – the effect of oxygen deprivation – and once got stuck counting to ten. “Now I look back on it and go, ‘Oh my gosh, I can’t believe I did that. That was crazy!’” She says. “My body took a lot of stress. It was hard work, but really worth it.”