Robert D. Glatter, MD: Hi. I'm Dr Robert Glatter, editorial member and advisor for Medscape Emergency Medicine. With the recent spate of deaths of climbers on Mount Everest filling the news, it seems like a good time to review the dangers associated with mountain climbing in relation to managing altitude illness.

In order to do this, I want to turn to Medscape's own sports medicine columnist, Bert Mandelbaum, an orthopedic surgeon and sports medicine physician who just happens to be an avid mountain climber. Burt is co-director of medical affairs at the Institute of Sports Sciences at Cedars-Sinai and director of the fellowship and foundation-affiliated practice at Cedars-Sinai Medical Center in Santa Monica, California.

Welcome, Bert. It's really a pleasure to have you join us for this important topic.

You Are Only as Strong as Your Weakest Link

Glatter: Let's begin by talking about altitude and the evils of altitude and hypoxia.

Bert R. Mandelbaum, MD, DHL (Hon): As you mentioned, Robert, I love being a climber. I also love hiking and diving. As a physician, I love the interplay between physical and physiologic adaptation and some of the untoward things that can occur from a medical approach.

The first thing that comes to mind is all about the details. You're only as strong as your weakest link when it comes to these sports. With Everest or any climb—Everest is 29,000 feet—you encounter the most amazing hypoxic environment. We go up there and there's a low barometric pressure, oxygen is not available, and our hemoglobin is not saturated. You have to prepare, and there are lots of details.

In the words of John Wooden, failure to prepare is really preparing to fail. In these situations—and this is what we've seen at Everest over the past few weeks—people are not focusing on those details.

Glatter: Right. Your point is to focus on details and preparation, which really speaks to the heart of preparing for any sport or endeavor that you undertake. In the setting of going up a mountain, the idea of acclimatization is the key principle. Can you talk about what that means and how you go about that when you start off on any type of climb?

Mandelbaum: Acclimatization is really like everything we talk about; it's about concepts, technique, and technology. First, for the concepts of preparing and acclimatization, you have to acclimatize physically, which is getting in shape, and then also physiologically. It takes training.

We have a variety of approaches. We've learned over time that we prepare using a high-high-low approach. You sleep high, you train high in a low-intensity wave, and then you go to low altitude and train in a high-intensity wave. The high-high-low approach is something we've learned over time in preparing people for altitude.

As you get closer to the climb, you have to think about the issues of acclimatization and how long it takes to go to a certain altitude. For every kilometer, it takes 11.4 days to acclimatize to an altitude. When you go to 8800 meters, it takes 88 days to acclimatize. You never reach full acclimatization, but that's the physiologic adaptation that you see. You have to consider the training, nutrition, fluids, progression, and medicine you can take.

Hydration and the Five-Layer Rule to Avoiding Hypothermia

Glatter: That brings, in terms of going up the mountain, the issues of hydration and fighting hypothermia. Can you speak to that a little bit? What are those principles?

Mandelbaum: Again, you're only as strong as your weakest link. Let's talk about hydration. When you're climbing, you have to drink 4 or 5 quarts of fluid per day just to stay ahead of the game. You have to think nutritionally. In terms of carbohydrates, the recommendation is about 70% overall.

You have to have the right clothes in terms of not sweating too much because when you do, you have a tendency to become hypothermic. You have to think about multiple layers. I like the five-layer rule. You have to think about putting it on, taking it off, and having lightweight layers that are protective of wind and the environment.

These details are incredibly important. If you have everything right and, all of a sudden, you're sweating so much that you become hypothermic, then you lose the game as well.

Everyone Is Prone to Altitude Sickness

Glatter: I think it's important for everyone to be aware that anyone who is traveling to altitude is at risk, regardless of fitness level, age, prior medical history, and prior travel to significant altitude. There are risk factors that we see. Maybe you could talk about who is prone to get altitude illness. Let's jump into discussing mountain sickness.

Mandelbaum: The first issue is that everybody is prone. I don't care what your maximum oxygen capacity is. It has a lot to do with the rate of ascent. The recommendations are to start under 10,000 feet when you start climbing. Never go above that. If you fly somewhere, don't start at that level. Start under 10,000 feet and then progress from there.

You should never progress more than 1000 feet per day for 3 days in succession. On the fourth day, you should rest at that altitude. Those variables about the rate of ascent are key to acclimatization overall. Where you sleep is also key.

I've been around people who I thought were the best athletes—much better than me—who couldn't acclimatize early on to some of the climbs because of these variables. It has to do with the physiologic makeup and things we don't fully understand within our bodies, such as our hemoglobin type and so on.

Glatter: There are certain things we can do, such as avoiding alcohol, sedatives, and being smart while we're climbing. Obviously, for nutrition, you talked about eating more carbohydrates to gain more energy.

Moving on to mountain sickness, what are the first symptoms someone might experience?

Mandelbaum: The first thing you feel is a headache. You were telling me earlier about the first time you went up the Jungfrau and you felt that headache. You feel your heart rate go up, maybe you don't feel quite well, and your stomach is upset. Why is that happening?

Your heart rate is going up, you have vasoconstriction of your GI vasculature. The pulmonary vasculature begins to vasoconstrict as you go there. You get that headache and you begin to not feel well, including fatigability and some shortness of breath. Those are the cardinal, early features of acute mountain sickness.

Glatter: We talk about cerebral blood flow being one of the causes of the headache, physiologically. We see increases in blood flow, which has been measured through different ultrasound techniques and even by transcranial Doppler.

Medications to Help You Ascend

Glatter: Now, getting to the medications, there have been multiple studies published.^[1-3] We often look to Diamox (acetazolamide) or dexamethasone—and ibuprofen—for people who've had a history of altitude illness.^[1,2] It's something that is quite attractive and may have fewer side effects. Can you speak on that?

Mandelbaum: I've tried either and both. Diamox and ibuprofen work by different mechanisms.^[1] Diamox is a carbonic anhydrase inhibitor and secretes more carbonate. Trying to keep up with the respiratory alkalosis in a preventive way, for me, has been successful. I would say that about 70%-80% of the time, Diamox is successful as a preventive.

Ibuprofen is more for that headache you described.^[3] It can be very helpful as an anti-inflammatory and make you feel more comfortable. Sometimes it makes your stomach even more upset in the big scheme of things, so you weigh the two overall.

Glatter: If you had to recommend one or two things that you're going to take away from mountain sickness before you start climbing, would you tend to go with dexamethasone or Diamox as your go-to?

Mandelbaum: I would probably start with the Diamox as the first step. It depends on where we're going. Are we going to Mount Whitney at 14,500 feet, Kilimanjaro at 19,300 feet, or Everest at 29,000 feet? Again, it depends on the details.

High-Altitude Cerebral and Pulmonary Edemas: Descend to 3000-4000 Feet

Glatter: Got it. Mountain sickness morphs into something called high-altitude cerebral edema (HACE), and that's always a dangerous thing. Could you talk about that and the dangers?

Mandelbaum: First, how do we identify that a patient, or you or one of your party, has it? It's really about that headache. It gets more intense and you begin to see more nausea and some vomiting. You see ataxia. The last phase on the spectrum of severity is the coma. After the confusion and bad headaches, that's what you begin to see.

In that setting, you have to think about dexamethasone immediately. The most important thing is getting the climber down to 3000-4000 feet once you identify symptoms of HACE.

Glatter: Absolutely. I think descent is the definitive treatment and we always want to stress that. Certainly, the other measures and dexamethasone can help.

Moving on to the next syndrome, high-altitude pulmonary edema (HAPE). That could start in a very subtle way, too, with a little shortness of breath, but it can progress significantly. Can you comment on that?

Mandelbaum: Interestingly enough, Robert, in this spectrum, this claims more lives than cerebral edema or acute mountain sickness. Pulmonary edema is from vasoconstriction of the pulmonary circulation. That causes, first, shortness of breath, exercise intolerance, and lastly, a dry cough. Those are the cardinal features of HAPE.

When you have those symptoms, as you just said, you have to descend rapidly, get below 3000 or 4000 feet, and then you'll begin to see some of these symptoms abate.

Ginkgo Biloba, Hyperbaric Sleeping Tents—Are They Worth the Hype?

Glatter: There are some people who talk about natural remedies. I'm not sure what your position is on Ginkgo biloba or cocoa leaves. Some people are more homeopathic. Are there any data to support the use of these?

Mandelbaum: I haven't seen any data, but I haven't seen any downsides. For those who want to be homeopathic, I don't see the downside in those situations, but I don't see the upside either. There haven't been any great studies.

Glatter: There is also some thought about sleeping in tents before you ever go on your trip, sort of at a normobaric hypoxia before departure to high altitude. Do you have any thoughts about that? Have you ever heard of anyone doing such a thing?

Mandelbaum: We've worked with athletes in terms of these hyperbaric tents. Considering the concept of sleeping high, this affords you that opportunity. If you're from New York City and want to do one of these climbs, that will help with some of the acclimatization. It's not going to get you all the way there, but it may help early on to build your red blood cell population.

Mount Everest—An Anarchic 'Deathtrap'

Glatter: Let's move on to Everest now and some of the issues that we've seen in the news.^[4] Thinking about that big picture that we discussed earlier, of people lined up to summit and all the dangers of overcrowding—let's dive into this. What is really the root cause of what we're seeing happen on Everest?

Mandelbaum: It's really anarchy overall. For the government of Nepal to give 381 permits is a set-up for failure. We are back to the idea that not preparing is preparing to fail. This situation of nearly 400 people at base camp with no order, organization, permits, or screening of who's best, who is or isn't experienced, who the guides are, or what their qualifications are, is really set up for disaster, and that's what we've seen.

Glatter: In terms of developing a governing body that we talked about earlier off camera, including the United States taking the lead and developing a federation with bylaws that would behoove everyone to increase safety for the sport and to have some law and order, so to speak...

Mandelbaum: I grew up with the International Olympic Committee, the United States Olympic and Paralympic Committee, the Fédération Internationale de Football Association, and other international organizations that do just this. It's about prevention, maximizing performance, and taking care of problems when they occur. There needs to be some type of international organization.

This is a multinational group of climbers who are there. We have to think about who is going to lead this type of federation, which develops criteria for all of the climbers, the climbing organizations, how many permits, what grade, watches the weather, and puts out various issues about things that we just spoke about. I think that's key to do better for the sport.

Glatter: I think we're going to see a lot more deaths and suffering if we don't act on your recommendations. There has to be something done very quickly, because that scene that we saw this year was such a wakeup call to everyone. It's really a deathtrap.

Mandelbaum: It's a tremendous deathtrap. Imagine hundreds of people sitting in this death zone, at 28,000 feet with no oxygen or running out of oxygen, and they can't move one way or the other. It's really an anarchic, random environment with the most stressful conditions. We've got to do better from a medical standpoint and from a sports organizational perspective.

Glatter: The Nepalese government needs to be aware of this. Their desire to take permits and the economic benefits that they're reaping may be coming at a significant cost.

Mandelbaum: Very much so. This is like many other issues we're dealing with in our world. As physicians, we have a role in this. Obviously, these are very medically related challenges that we have to think about. We have to organize ourselves and be part of this.

Final Eloquent Words

Glatter: Bert, if you could give us five key takeaways from our discussion for our audience, I'd really appreciate that.

Mandelbaum: I think the most important thing is that this is about details. We are only as strong as our weakest link. I love the expression, which is from the British military, of the eight Ps:

Proper prior planning and preparation prevents piss-poor performance.

Glatter: That's quite eloquent.

Mandelbaum: It's the takeaway message here because it really is about that. It's a lot of those details of training, nutrition, fluids, progression, and being studious and understanding. That's why it's such an interesting topic.

Glatter: Absolutely. I want to thank you for your time, Bert. This has been very instructive and very enlightening. I think your thoughts on this subject are incredible. Thank you again for joining us.

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References

1. Gertsch JH, Lipman GS, Holck PS, et al. Prospective, double-blind, randomized, placebo-controlled comparison of acetazolamide versus ibuprofen for prophylaxis against high altitude headache: the Headache Evaluation at Altitude Trial (HEAT). Wilderness Environ Med. 2010;21:236-243. Source
2. Sridharan K, Sivaramakrishnan G. Pharmacological interventions for preventing acute mountain sickness: a network meta-analysis and trial sequential analysis of randomized clinical trials. Ann Med. 2018;50:147-155. Source
3. Lipman GS, Kanaan NC, Holck PS, Constance BB, Gertsch JH; PAINS Group. Ibuprofen prevents altitude illness: a randomized controlled trial for prevention of altitude illness with nonsteroidal anti-inflammatories. Ann Emerg Med. 2012;59:484-490. Source
4. Schultz K, Gettleman J, Mashal M, Sharma B. 'It was like a zoo': death on an unruly, overcrowded Everest. The New York Times. May 26, 2019. Source

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