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In January 2024, I traveled to Argentina with Dr. Sameer Sethi, my co-fellow at the University of Vermont, and Dr. Aaron Brilhart, a faculty member in the UVM Wilderness Medicine Fellowship Program. We flew into Mendoza with the excitement of being in a new place for the first time. We had two main goals on the mountain: 1. Spend time evaluating patients in the high-altitude clinic at Plaza de Mulas, and 2. Work on the research agenda we had been preparing for months.

The Goal

I was happy to just be traveling to a new place and being in the mountains surrounded by like-minded people. My focus as a fellow was to gain experience in the evaluation and management of climbers who experience altitude illness and other medical issues in the remote mountainous region of Aconcagua. I wanted to see how Argentinian physicians managed patients and expectations on one of the most challenging mountains in the world. We also had research projects that we had been preparing and were anxious to get started on. We had important questions that we felt could chip away at some of the unknowns in the management of high-altitude illnesses.

The Mountain

Aconcagua is a unique mountain that is underestimated by many people due to its non-technical nature.  However, it remains the highest mountain outside of Asia at 6,962 meters. Many people succumb to altitude illness and a few climbers die every year, often due to inadequate mental and physical preparations. 

The vista from Confluencia to Mulas. (Andrew Park) 

There are around 4,000 people who trek on the Aconcagua route in a given season. It is mandated by the park that all climbers must be screened at the medical clinics before progressing to higher elevations on the trekking route. This provides an important safety screen for the climbers and serves as an indirect benefit to the rescue providers and evacuation crews that must care for these patients in the event of complications on the mountain. 

The Clinics

The two clinics on the trekking route of Aconcagua are at Confluencia (3,390 meters) and Plaza de Mulas (4,300 meters). There is an additional physician stationed at the park ranger station at Nido de Condores (5,550 meters) for emergency purposes and to assist with rescues only. 

The physicians conduct an interview with the climber and a brief physical assessment is performed. Their heart rate, blood pressure, and oxygen saturation are taken and recorded on a card that is signed and kept with the climber. The climbers are asked about their prior travel and ascent plan. This is also an opportunity for the physicians to impart some recommendations regarding acclimatization schedule, water intake, and rest.  It’s an extremely important time of interaction between the climbers and the medical staff.  

With thousands of climbers and the frequency of altitude illness, this provided a unique opportunity for me to see in real-time the complications people experienced in this setting. Working with the Argentinian physicians of Extreme Medicine also provided valuable insight into patient interactions and gave context to the environment and the background of this mountain.

Clinic Team, left to right: Andrew Park, Ivana Sosa, Aaron Brilhart, Gaston Pisciotta, Sameer Sethi. (Andrew Park)

Park rangers observing the care of a climber who is being treated for frostbite. (Andrew Park)

The Dining Tent

We spent a lot of time in the dining tent at Plaza de Mulas.  It was a mix of people from different groups and an occasional solo climber. The languages spoken were as numerous as the number of opinions on acetazolamide use, but much more beautiful and fun to listen to. We made many new friends and shared many hopes and baskets of our local delicacy, stiff bread. The anxiety was palpable, with many medical questions and dotted anecdotes of happenings higher on the mountain. We shared apprehension and excitement and gave each other what luck we had to give.


When we weren’t providing medical care, we were trying to acclimatize ourselves. We had our own plans to move up the mountain to spend some time at Nido de Condores where the emergency responses and rescues would operate for people attempting the summit. Our first was a day hike to Cerro Bonete (5,074 meters).  In addition to seeing the neighboring Chilean mountains from the summit, we practiced a bit of scree skiing on the way down. Some were more successful than others.

Navigating the penitents, one of my favorite, unique physical aspects of Aconcagua. (Andrew Park)

Next, we had repeat trips to Camp Canada (5,099 meters) to set up a tent and leave some supplies.  On our second trip we would sleep there for the night. We would then move higher to Nido de Condores the next morning and portered all our own gear.  The front/back backpack set-up was a little much; my deepest respect to all the porters.

What a hike on this day from Camp Canada to Nido de Condores. (Andrew Park)

“Nido” was spectacular and barren, with frozen pools we would extract water from for our cooking and drinking. The following morning though would bring a reckoning. A combination of plummeting oxygen saturations for some team members and weather conditions that would prevent any climbing for two days left us with an easy decision given our main goal on Aconcagua. We returned to base camp and our goal of seeing more patients and working on research.

The Research

We interviewed many people as they came through the clinic and after they completed their medical screening. We wanted to learn more about the acclimatization practices of the climbers, and in those climbers who developed HAPE, we dove a little deeper. It was a fun, interactive time to meet other climbers from all over the world and learn about how they prepared for this trip and the big mountain. For some it was a dream in the making, and for others, it was a necessary step on their way to the Seven Summits Club. 

We would also spend time at the café at base camp and we even interviewed a few climbers there. However, we mostly played high-altitude card games and drank coffee. UNO was a comedy. As Oliver Sachs once described in his work with catatonic, post-encephalitic patients playing cards, we were dull and sluggish, feeling the altitude’s effect on our bodies.  

High altitude UNO. (Andrew Park)

It was interesting to talk to climbers and see patients with HAPE and start to see trends in real time. It was also fascinating to see climbers repeatedly put themselves in harm's way despite knowing the dangers. Short memories of traumatic events can be useful, but what determines one’s selectiveness in regard to retaining painful memories? Surely this happens in the city as well, but I can’t remember a time for me.

The Departure

With all the preparation for a summit and resting heart rates in the 60s, I needed to expend some energy. On the final day of the Aconcagua expedition, I decided I would run to the park entrance. 

The long run out of the park. (Andrew Park)

I would start at Plaza de Mulas at 4,300 meters and cover the distance of 15.2 miles to the park entrance. It would be the longest training run I’d ever done and especially at this altitude. I packed two liters of water, two ham and cheese sandwiches, a packet of energy bites, and two granola bars. I wore a hat, sunglasses, lots of sunscreen, running tights and my Musa Masala long sleeve sun shirt. 

The run by myself was a spiritual one. Surrounded by mountains, I was funneled down the valley and never had to make a directional decision for nearly five hours. My feet found the path worn down by the mules that passed before me and beside me. 

I reached excited states. I reached low states. I smelled ammonia and the cramps stopped me in my tracks.  Each step was bringing me closer to the known; to questions unanswered.  When I reached the park entrance at the end, I was surprisingly overwhelmed with emotion. Simply exhaustion? I’m not convinced.


After the mountain, our dining tent extended to the streets of Mendoza. Every night for an entire week we met for dinner at a different place in Mendoza. We rode bicycles to vineyards and olive farms. A safety pin for nail trephination eluded me on the streets of Mendoza, but was eventually found at a wedding dress store. The people are who I’ll remember the most. The summit eluded me, but this trip was completely fulfilling. See you in 2025?


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