Carlo Canepa, MD
Fellow in Wilderness Medicine at the Massachusetts General
Hospital
PGY-6
High Altitude Medicine in Nepal: Part 2
We’ve entered our second month of the high-altitude clinic
being open and the patient volume has slowed dramatically. While in April there
would be 15-20 patients per day, now we are seeing between 5 and 10. This
coincides with the decline of trekking traffic in the national park. Another
factor is that many of the guides, porters, and locals have been up and down
the trek 7 or 8 times. Their bodies have acclimatized to the lack of oxygen and
we no longer see as much altitude illness in that population. Trekkers will
still come in with AMS, HAPE, and HACE, however.
We’re about to see our 500th patient for the
season, with close to 50 with high altitude pulmonary edema and around 10 with
high altitude cerebral edema. We’ve had to helicopter evacuate about 15
patients so far, with another 15 at least opting to fly out on their own. This
does not include the likely dozens or hundreds of trekkers who get flown out at
higher and lower altitudes that never come to our clinic. This is a big change
from the last time I was here in 2012. The number of helicopters has
skyrocketed. Whereas before we might see 1 or 2 per day in the valley, now
there are up to 50 flights in a single day, for commercial reasons and for
medical evacuations. The industry has dramatically changed how trekkers plan
their treks. Many will hike up to Everest Base Camp and then choose to take a helicopter
down, rather than to hike down several days. Similarly, trekking companies are
aware that if one of their team members gets ill while hiking there will always
been helicopters available to evacuate them, weather permitting. We even saw
one patient who was evacuated off the trek with acute mountain sickness via
helicopter to Kathmandu and then returned for a scenic helicopter flight only
to get symptoms of HACE during the flight. She was evacuated again via
helicopter.
This means this extreme environment with its lack of
available oxygen is now readily available to a wider population. We have seen
people in their 70s and 80s trekking up to 18,000 feet! Similarly, we
occasionally see parents carrying very young children (the youngest we have seen
was 6 months old). Although the data regarding children at altitude is not
comprehensive, it seems logical that the developing brain will not do well in a
hypoxic environment. We’ve also seen people who are tremendously out of shape
and ill-prepared for such an intense trek (with 6-8 hours days of hiking up and
downhill at altitude). We’ve also seen many people with significant
co-morbidities coming up the mountain, including auto-immune hepatitis,
coronary artery disease with multiple stents and bypass grafts, pulmonary
embolism, etc. Although the trek is now more available to all populations, it
also means that people are undertaking the trek without being fully prepared or
educated about the dangers of high altitude.
We give a free lecture every day at 3pm to educate the
public about the dangers of high altitude and signs and symptoms of high
altitude illness. Some days we have only a couple of participants and others we
may have more than 30. People are always surprised at how dangerous even
trekking at such an altitude can be. Every year there are deaths in the valley
from high altitude illness and this year is no exception, with approximately 8
to 10 tallied thus far. We do our best to educate attendees so that they can
then be on the lookout for trekkers and locals who appear ill.
A few of the more interesting cases we have seen recently
include a homeless woman living among the mountains with severe frostbite of
her feet, high altitude cerebral edema complicated by GI bleeding after severe
vomiting, and a likely case of appendicitis at high altitude, which we treated
with oral antibiotics. We have made a few house calls while here, trekking
about 2 hours in the night and light snow to meet a patient with severe Acute
Mountain Sickness who was unable to walk on her own due to severe weakness. We
had a pediatric abdominal pain that was severe with fever that looked like a
liver abscess on bedside ultrasound. He was treated with IV antibiotics and
evacuated. Another female trekker who was taking acetazolamide and
ciprofloxacin continued to feel ill and was diagnosed with a high-altitude
pregnancy. Her medications were stopped and she made her way down the valley.
One byproduct of working at a high-altitude clinic is that
there is a lot of downtime. After the clinic closes at 5pm we may see another 1
or 2 patients that come in overnight. Otherwise, much of the evenings are free
to ourselves. We have a cook who prepares three meals a day for us (8am, 12
noon, 6pm), and I brought another bag’s worth of dried fruit and snacks. Then
we’ll often watch a movie after dinner together from the wide array of DVDs
available at the clinic. I’ve read about 10 books while here and have also
worked on research projects and write-ups that had been previously ignored. We
also have days off where we can trek throughout the valley. Between the three
physicians, we’ve been to Everest Base Camp, Kala Pattar, Ama Dablam base camp,
the central town of Namche several times, Island Peak base camp, as well as the
nearby Gokyo valley. We have gotten a chance to explore the area in great
detail.
Lastly, my research project is coming along well. I had my
second set of research assistants pass through the valley and altogether we
have thus far recruited 222 participants for the study. The goal is to reach
288 by the end of May. I have tried to recruit at different altitudes, with the
higher altitudes covered well, which means I’ll have to descend to lower
altitudes to recruit some more. Recruiting from big, English-speaking tour
groups has proven to provide the highest yield of participants. Otherwise, it’s
mostly hanging around the tea house dining areas and randomly approaching
strangers to ask them if they would like to be part of a research study. That
approach generally works fine, but the trek is very international and so there
will often be huge groups of non-English speakers. On a different note, the
daily temperatures hover around freezing and the nighttime temperatures drop
below freezing, which make convincing participants to have a lung ultrasound
with their chests exposed and cold gel applied a bit difficult.
Altogether my experience has been as I expected
it to be: a lot of altitude medicine, a lot of primary care, excellent hikes in
the mountains, and not-so-easy-to-conduct research. Working and volunteering
for the Himalayan Rescue Association (HRA) is almost a rite of passage for
anyone interested in working and conducting research at high altitude. I feel
fortunate that I had the opportunity to spend two months working with such an amazing
organization and in such a unique environment. This experience has encouraged
me to continue to work and play in the mountains and to pursue further research
ideas in high altitude physiology. It has been a once-in-lifetime opportunity.