Many of you will have taken acetazolamide (Diamox) and will know its effects, both good and bad. The Birmingham Medical Research Expeditionary Society’s (BMRES) 2016 expedition to Ecuador aimed to study its effects on the exercise tolerance of partially acclimatised individuals. They also hoped to climb Chimborazo – the furthest point from the centre of the Earth.
Their account makes for interesting reading, not least because the conditions managed to catch out the very experienced Chris Imray. We also have an interview with Hannah Lock, one of the medical students on the trip, telling us how she got involved, and her own high and low points.
It is 5am, we are at about 6100m and the temperature is between -20C and -25C. We had been making slow upwards progress on the glacier for about six hours. The climbing involved front-pointing up an apparently interminable 45-degree boilerplate ice slab. We were inching towards the furthest point from the centre of the earth.
A series of unfortunate events combined with a couple of schoolboy errors meant that the situation was rather more serious than we had planned. The most immediately perilous being the lack of snow cover on the glacier (be it from global warming or the recent El Nino) and the resultant sheet ice being far more challenging than we had expected. The unexpectedly severe cold, the altitude and the adverse effects of acetazolamide on performance in partially acclimatised individuals further compounded the situation.
Whymper in Ecuador
Through a quirk of geology and the result of the non-spherical (technically, ‘oblate spheroid’) shape of the earth, the summit of Chimbarazo in Ecuador (6310m), is 2220m further from the centre of the earth than the summit of Everest at 8848m.
When English mountaineer Edward Whymper climbed the Matterhorn in 1865, four of his party fell to their deaths on the descent. As a consequence, Whymper re-directed his interests from climbing to studying the potential adverse effects of altitude. In December 1879, a European expedition consisting of Matterhorn veterans Edward Whymper, Jean Antoine and Louis Carrel arrived in the port of Guayaquil, Ecuador with the aim of climbing Chimbarazo. With difficulty, and after a 16-hour summit push, the three reached the summit. Louis Carrel suffered severe frostbite to his feet during the descent. At 6310m this was the highest peak to be climbed at the time (1880).
The BMRES 2016 trip to Ecuador was a return trip following an earlier expedition in 1978. The original expedition demonstrated the benefits of acetazolomide in acute exposure to altitude and resulted in a paper being published in the Lancet. The main aim of the 2016 expedition was to investigate the effects of acetazolamide on exercise performance in partially acclimatised individuals.
Flying to Quito
Leaving Birmingham for Quito via Schiphol was not straightforward, in that we thought we had two pieces of luggage booked onto the flight, one personal and one for the experimental equipment. After a protracted debate and discussions involving mouth-watering excessive baggage fees we finally left the UK, wallets intact.
Quito is at an altitude of 2850m and on our second day we took the Quito Teleferico to 4100m and then climbed up to the summit of Pichincha Volcano, altitude 4784m. This ascent profile, exceeding all recommendations, resulted in a number of headaches and lost appetites, but on returning to Quito most symptoms resolved.
Ascent to the Whymper Hut
The expedition ascent was by profile of 2800m, two nights at 3800m, 4800m by bus and then by foot to 5000m. This rapid ascent profile again resulted in moderate Lake Louise Acute Mountain Sickness Scores. In total, we spent five nights at 5000m completing the experimental program. The facilities of the recently refurbished Whymper Hut were excellent, with running water, flushing toilets, reliable solar power, and great catering. The support from John Paredes and his team made this a potential altitude research station to rival the Marguerita Hut, Italy (4559m), the Pyramid Research Station, Nepal (5050m) and Chacaltaya, Bolivia (5250m).
There were four days of exercise experiments, the first two days being a double-blind study of losartan vs. placebo and the second two days being an investigation of the effects on exercise of introducing acetazolamide to partially acclimatised individuals. There was an approximately 15% reduction in my maximal exercise test on acetazolamide. Indeed, when we set off at 11.30 pm for the summit, my extremities tingled with exertion and carbonated drinks had an unpleasant metallic taste.
Fredy and Marco, our guides, set a steady pace. I was initially able to match it, along with fellow expeditioners Owen, an FY2 and Cas, a freelance programmer/engineer. We climbed steadily through the night into the increasingly cold, thin air. Cas began to lag and decided at about 6000m to return back to the Whymper Hut with Marco. Owen, Fredy and I continued more slowly.
In the unexpectedly cold, thin atmosphere I was beginning to lose the feeling in both thumbs and a couple of fingers; my toes were not much better. My water bottle, inside my rucksack, had begun to freeze. Based upon a temperature recorded at 3800m of -5C, the temperature at 6310m was likely to have been -22C, reckoning -1C for every 150m altitude gained. Fortunately, there was no wind. I have lectured all over the world on frostbite and will often hold my hands up to declare that frostbite can be avoided by good preparation, equipment and an appropriate and timely decision to turn around. My current predicament felt like a series of school-boy errors misjudging the cold, the altitude, the ice and the adverse effect of acetazolamide on performance at extreme altitude.
Fortunately, we began to move a little more quickly as the gradient eased toward the summit and we arrived just as the sun began to rise. A few photos and then a rapid descent back to the Whymper Hut in time for a late breakfast. Cas had arrived back a couple of hours before us and had been diagnosed with mild High Altitude Cerebral Oedema (HACE) based on a headache and some ataxia. Owen and I had coughs and had developed comet tails on chest ultrasound consistent with extra pulmonary lung water or pulmonary oedema (HAPE).
In hindsight, being better acclimatised, not using acetazolamide when partially acclimatised, being better equipped for the cold and choosing to climb a route that was out of condition all contributed to making this a more challenging ascent than we had expected.
Owen has just started the UK Diploma in Mountain Medicine and is my mentee. In Dave Hillebrandt’s words he is looking for ‘quality mountain days’ and in my opinion this journey to the furthest point from the centre of the earth certainly qualifies.
A Medical Student’s Perspective – Hannah Lock
Had you done any research before? / I had never been involved in research of any kind before attending the monthly meetings of Birmingham Medical Research Expeditionary Society (BMRES). It crossed my mind that taking on extra work whilst in my final year of medical school was potentially a bad idea. However, when the group began to discuss the prospect of another major expedition I was extremely keen to be involved, even more so when Ecuador was picked as the destination. I had travelled in South America before, so was always on the look out for opportunities to go back. A trip combining my love of mountaineering and travel, with altitude medicine research sounded right up my street.
How did you get the time out to go? / As a medical student, getting a place on an expedition like this felt like a huge opportunity and a privilege. The main obstacle was convincing Warwick Medical School to let me take time out of my Obstetrics & Gynaecology block to go on the trip. I negotiated to make up the time over the Christmas holidays: sitting in a hysteroscopy clinic on Christmas Eve might not have been the highlight of my medical school career, but it was well worth it when my bags were packed and I was boarding the plane with the rest of the team two weeks later.
Did you know anyone on the trip? / The team consisted of Consultants and junior doctors from a variety of specialities, a couple of engineers, some physiologists and five medical students from three different universities. Although I knew some of them, there were some people I had only met briefly before the trip, and not many that I knew well. Still, slogging it up to 4700m from 3800m after a morning of blood taking and cognitive tests was a great way to get to know people better. The amazing mountain views, combined with mild nausea, headaches and shortness of breath really bonded us together.
We heard there was a race involved…? / The competitive streak of about half the group was tested on the descent when we decided to race down the valley back to our lodge. As I was running, trying to prove I could keep up, wishing I had my race pack and running shoes on instead of a large rucksack and B3 boots, I had the horrifying realisation that my 2L urine collection bottle with its very unreliable lid (part of a study!), was bouncing around in my bag. With the finish line in my sights, and my position in the race improving, I knew I had to forget about the potential spilt urine fiasco that awaited me and push on. Once in the valley bottom Chris joined my route and overtook me, the altitude taking its toll now we weren’t heading down hill. Luckily at the last minute I found some extra energy and we both crossed the finish line together. The prize for me was opening my bag to find the seal of my urine bottle had held, and by some miracle my bag was dry.
What did you learn? / Being both a researcher and a research participant on this expedition gave me great insight into the research process, especially since there were several studies running simultaneously. Every morning I helped on the blood team, taking 20ml venous blood samples from each participant, centrifuging the bottles, and taking serum samples from them.
This was a great chance to practice my venepuncture skills, but embarrassingly I still managed to miss a huge vein when Chris came for his bloods one morning, which I attempted to blame on the fact my head was a little fuzzy since it was our first morning at 5000m.
I also undertook my own small project looking into cognitive dysfunction associated with high altitude using a simple paper-based reading test called the King-Devick test. Due to the late application of my project to the ethics committee, it was touch and go as to whether I would get permission in time for the trip, but luckily, after several late night emails from a lodge at 3400m, I got the permission with only hours to spare before phone signal and internet access behind.
What were the highlights of the trip? / Spending a week in the Whymper hut at 5000m completing exercise tests and having a crack at the summit of Chimborazo a couple of days after Chris. Waking up to incredible sunrises, foxes hunting for food, and watching the weather and views of the mountain change over the course of the day.
Despite these, there was still a definite air of cabin fever by the end of our stay, so descending the mountain to spend our last two days in the beautiful town of Banos, with its huge supply of free oxygen (at an altitude of 1800m) was a great idea from our brilliant guide, Fredy.
After a night of sampling the local cocktails, half the group headed out for a morning of white water rafting which turned out to be a hilarious battle between the two rafts teams. Lush fauna covered the steep mountainsides either side of the river, with huge, wild orchids contributing stunning flashes of colour. Vultures circled above whilst some sat on the river banks, watching our progress and giving us the impression they were ready and waiting for one of us to fall out into the rapids. Luckily, although we had a few man-over-board scenarios, we managed to rescue our crew before the vultures got a look in.
This expedition to Ecuador reignited my love of South America, introduced me to some amazing people and great new friends, and opened my eyes to the endless opportunities and adventures that medical research can bring.
The Birmingham Medical Research Expeditionary Society is an inclusive society open to everyone, medically qualified or not. BMRES meets at the Medical School in Birmingham at 8.00 pm on the second Tuesday of the month. The Society tends to do one expedition to the Greater Ranges every two or three years, a European Alps based research expedition every two to three years as well as an ongoing UK based research program. BMRES is keen work collaboratively with other research groups and usually hosts a national altitude conference every few years, focusing on encouraging young researchers to present. The Summer Walk – an attempt on the Welsh 14 – is the next outdoor event planned for June 2016.