High Altitude Risks. Lessons from Everest

by Marybeth Lambe MD FAAFP Snoqualmie Valley Clinic Snoqualmie Washington

Being Fully Informed on Altitude Risks

You may not have even noted the recent death of an American climber at Everest, the eleventh person to die on Everest this year. When so much news pouring in all the time, crucial, troubling; what captures you, in your own life is difficult to predict. For me, the deaths on Everest, a mountain I will never climb, were yet poignant and reminded me of how very mortal we always are, even in our moments pursuing cherished dreams as were these climbers. Their deaths, from complex and diverse cause, were principally rooted in high altitude risks. No, you may never climb an extremely high peak but knowing more about high altitude dangers may save your own life. In some terrible way, attending to the myriad dangers’ altitude illnesses can bring may have saved some of these climbers lives too; we can never know, can we? You need not fix all details of Boyle’s law, physical altitude versus pressure altitude knowledge but you would be well served to understand how vitally our bodies need oxygen, what changes occur as the human body does what it must to assuage that need, and what confusing symptoms may result. Why are you reading an article you believe directed toward those aspiring at mountain climbing? Because it is not written only for the elite climber but for almost all who may come up from sea level one way or another.

Mount Everest, received its newest name in honor of Surveyor General of India George Everest who, it is told, was mortified to have such a magnificent mountain share his name. Too much renown especially this mountain already spoken of in the two countries it boundaries as “Chomolungma,” (Mother Goddess of the Universe) in Tibet and “Sagarmatha” (Goddess’s Forehead of the Sky) in Nepalese. Everest has held a romantic ideal in our western hearts, dreams, and lore; climbers flock to achieve the summit. Idealized, and not as brutal to climb as K2 or Annapurna, Everest is still a profound challenge of a lifetime. Somehow, in the last two decades, the Nepal side of Everest has also developed some troubling overcrowding and perhaps attracting less tested climbers on the Nepal approach; climbers who can put forward the fees and try their dreams too. Nepal has been putting out permits at rates over 270 a year since 2011 (in 1996, concerns for delays engendered by overcrowding were sounded). An upswing in deaths on the descent suggesting too much time in the death zone, possibly from delays, occurred in 2011, 2012, 2013, 2017, and now 2019. These deaths show climbers walking down beyond exhausted, stopping to “rest” and never getting up again. Other deaths possibly linked to pushing a body beyond endurance too long, too hard against all judgment likewise imply being slowed in extremely high altitude with all the attendant risks. This article reviews altitude risk in general and not just for those in the extremely thin air of Mt Everest and other such peaks.

This reminds us patterns must be heeded if they are to save lives. The pattern on Everest has been there for many years now and was only interrupted in 2014 by a terrible loss of life from an ice avalanche at Khumbu Icefall killing 16 working Sherpas on their mountain. It was at this same Khumbu Icefall in 1970 that 6 Nepalese Sherpas also died in an avalanche. In 2015, no one summited as a7.8 magnitude earthquake tore through Nepal and shook Mount Everest killing 24 people on the mountain. it left devastation below. The quake killed more than 8,000 people and injured 21,000 others, leveling much of Kathmandu the surrounding rural region.

Long motionless lines of up to 200 hundred climbers at the Lhotse Face at 25,000ft, waiting even higher up as oxygen tanks empty, body heat drifts away and cerebral hypoxia makes any thoughtful decision an oxymoron. In 1996, 8 died within 36 hours of the summit. Track this data: 72 people made it to the summit in all of 1990. 234 climbers summited the peak in a SINGLE day in 2012. In 2013, on May 19th 150 climbers climbed the last 3,000 feet of the peak from Camp IV all within hours of each other, causing frequent, potentially lethal, stalls. Annual totals: In 2013 800 climbed, with 658 summiting. It may not be possible to shove more than 200-250 climbers through on a given day; more than 650 summiting all told in a season. Therefore the available good days matter tremendously. If you intend to summit into what sum will you be crushed? How spread out might the mob best survive? What can your luck be in terms of those skill levels in front of you and how quickly they can move up and over each obstacle? It matters whether you arrive in time to summit, (or not) and then descend with your life. Understanding altitude and some math may be all that keeps you from becoming another body left behind in the end. The climber on Everest is attempting, not merely the task before them, but to perform this climb and to summit through a funnel of other climbers. This setting has been present, more or less, for well over a decade; more likely for the last 20 years. A few slowdowns, such as a less inexperienced climber or someone struggling before him or her, has the potential of emptying everyone’s fuel tank, altering risk sets. Data from 2006 onward (possibly 1996 onward), save for 2014, 2015, ALL available data demands a climber build an understanding to include Nepal permits have been going out at a rate of over 270 for quite a while. They are now up at a rate of over 370-380 each year. It is not an aberration but a truth. We fool ourselves when we pretend what happened in 2019 was unusual on Everest. It had become the norm interrupted only by a 2014 killing ice event and 2015 quake. Build a plan with data that occurs regularly. See the likely death coming and find a way to see the next dawn. Don’t act as if May 2019 was rare, odd, or anything other than a building pattern. If the 2019 deaths seem something has changed, the change was years ago. Catch up, before it overtakes you. It is past time Everest climbers start seeing the long pattern, indeed plan for what the climber will do if his climbing window is further narrowed and he/she races out to ascend only to find everyone else is leaping at the same small window. Since at least 1996 when 11 climbers died, and permit numbers were high, if the few days of available summiting are chopped down by bad weather there will be a crowded scramble for the summit if the weather clears. How many years will it take to see this? Crowds contribute only one factor. Consider how one's luck depends on if the available days are cut in half if you happen to have one or several less experienced or struggling climbers directly in front of you slowing the one lane route.

 Today, the climber on Everest needs to have strict prest times in the death zone calculated for every possible crowd and delay setting he/she might face. One cannot use hypoxic judgment at the moment and the day of presummit cognition.

In 2012 a photo released from German climber Ralf Dujmovitsshows a disturbingly long line of waiting climbers who appear to be stalled in single file, waiting their return to move forward. This sneaking long motionless trail of climbers was ominous if one considered these were people waiting, waiting, waiting, all of them paused at a dangerous altitude. How soon will they become exhausted yet not recognize it and keep pushing upwards? Without reserves and possibly without enough brain support, reducing the brain’s ability to think. Any of these climbers trapped in this motionless line, did they have a plan for how to determine when to abandon the ascent and live, how to know it was safe to continue? If you didn't know this photo was almost a decade prior to the ones now circulating and documenting crowding in May 2019 at Everest in the final summit pushes, you too might believe headlines insisting crowding as a risk is new on Everest and climbers were taken by surprise. Since at least 1996, even when permits were issued at lower rates, many have cited concerns. The scope of the problem stands out more prominently when there are very limited weather windows for a climber’s burst to the summit hampered by every other climber attempting to accomplish the exact same feat. In other words, some years this risk roars to life and in some years, crowds can have room to make their way better dispersed. Also, humans have a sensitivity to gory drama. Crowding was suspected as a factor in some deaths in 2006, and more certainly the impact of an increased number of climbers without enough experience and 8,000 meter credentials began to be a was a factor in many of the Everest deaths but there were fewer total deaths on the mountain. It appears, for us to pick up data patterns, we attend to sacrifice and loss. Unbelievably terrible the way our minds attend but also true. We follow swings of danger and death but miss life-saving trends if they don't stand out. No one's injury or loss of life should be in vain. Until 1985, Nepal allowed only one expedition on each route to the summit at a time. 

In 2012, Song Young-il, 47, of South Korea, and his friend Song Wong-bin summited at 7 AM but were forced to pause for hours just 200 meters below the summit, waiting a chance to descend back down again. They suffered snow blindness, delirium, and hypothermia as they waited four hours for more than 300 climbers to pass before they could begin their descent. They became stuck once more, this time at a common bottleneck, 'Hilary's Step', the major obstacle between the summit and South Col, 3 hours below. Climbing down, at last, Song Wong-bin collapsed and died, never making it back safely to camp alive. 3 other climbers also died after early morning summit but likewise struggling to swim down through upward throngs.

Being slowed by others is most likely when the already limited weather window is further tightened by the precarious jet streams; when a potential of six days drops to a maximum of two or three, everyone is chasing the same hope for an ascent. Slowing created by too many people amplify risks and intensity altitude illnesses. It also escalates other dangers such as hypothermia, dehydration, and others. The longer one is kept trapped at a killing elevation, the more risk exposure can occur. This is not to suggest a climber is without choice and judgment; after so many years of this phenomenon arising, with this number of permits occurring and offered to those with relative inexperienced, it is unimaginable that a climber today would be unaware of this situation which has now existed for greater than a decade. Just as one would plan for any other condition to be experienced, a game plan to deal with how to summit in the face of this situation would be paramount.

Though less died, spring climbing on Everest in 2013, was also marred by congestion with too large a number of climbers making their way to the summit In 2013 alone, 658 climbers reached the top of Everest. Eight people were killed and these deaths were felt to be related to people getting in each other’s way. Climbers made the wrong choice in the years of 1996, 2008, 2011, 2012, and 2013 yet still, some discuss decision making when crowding alters choice as if this has never been seen until this season, this Everest, these climbers who died on their descent. If the last 20 years have taught us nothing, how might lives on Everest be saved? Climbing season on Everest is, at best, a very few days shoved between treacherous, difficult to predict, and sudden storm. A climber must be positioned perfectly to take advantage of jet stream pauses and do have such luck as to be ready to capitalize on these openings for summiting. These brief windows of climate stability, of climbing opportunity, inevitably produces what is seen more and more often every spring: a hurrying hoard of climbers all pouring onto a small narrow and packed trail. There is no sometimes no room for anyone to move. This is a concern because it creates longer time periods in unsuitable extreme high altitude. Oxygen canisters are used up during extended waits, climbers and their guides stalled int the death zone between 26,000 feet and the summit.

High altitude occurs where you may not even consider. Sitting in a modern day jet as you head toward a vacation or business destination you are of course in a pressurized air cabin. It may surprise you to know however that this pressurized air is at an equivalent altitude of anywhere between 5,000 to 9,000 feet. It is not unheard of for some to complain of symptoms which are essentially mild mountain sickness developing while sitting as a passenger on a modern aircraft flying across the United States.

At sea level, we live under a blanket of air which presses against us. Many do not realize, but it is this pressure that forces air into our lungs not simply air density itself, that allows for air exchange into our bodies and blood stream. At sea level, because air is compressible, the weight of all that air above us compresses the air about us, making it denser. As you travel up in elevation, the air becomes less compressed and is therefore “thinner.” This effect can be felt as early as 5,000 feet in those who are susceptible; more often above 8000 feet. This is what makes everyone connected in a way you will see to the losses of these elite dedicated climbers which, at first view, may seem disconnected from your own life.

While altitude illnesses have many symptoms and some of the more serious forms impact lung function and even impair consciousness, altitude has early and subtle impact on judgment and overall cognition. This is critical to grasp as high altitude may impair judgment potentially before one vet has awareness alteration is taking place. The brain normally accounts for 20% of total oxygen consumption. Under the high-altitude conditions of moderate to severe oxygen limitation, mental performance is impaired. Impairment in codification and short-term memory is especially noticeable above 6,000 meters and alterations in accuracy and motor speed occur at lower altitudes

For those for whom Everest is no goal, altitude knowledge will benefit you more than you know. Make it through the Everest portion and let the later info sit with you. High altitude, is even with you on a supposed pressurized jet plane. High altitude, it turns out, is more ubiquitous than you knew.

Extreme high altitude robs your brain of oxygen and prevents clear thinking. You cannot count on any clarity of judgment as you climb toward the summit; this cannot be at the scene decision time. Thought processes and decisions must be made prior to a climb into the low O2 death zone. One must have a plan prior to arrival, not leave it to an oxygen-starved brain to sort through, if too much time has passed, no matter how close the summit, abort the mission. Overcrowding is one manner in which a body and brain are trapped longer in dangerous levels of extreme high altitude for too prolonged and too perilous a time. On Everest, this risk should no longer be a surprise to today’s climber. It happened in 1996 and then with regularity in 2008, 2011, 2012, and 2013 as well as 2017. We think of the loss of those 11 lives list this spring. Tragic, and grievous. Yet, Everest experience possessed such data of over a decade. if you are a climber who longs for summiting Everest, think and know this history. Do not imagine you can make decisions after hours in the death zone. You cannot and death will come for you.

For most of us, extremely high altitude is not a condition we will experience. I am concerned that the discussion of overcrowding almost distracts from the reality and risks of extremely high altitude. Excessive fatigue, prolonged time in the death zone, loosening of judgment, extreme drive to reach the summit only to discover at the top that one has nothing left, all of these have killed climbers on Mt. Everest especially in high permit years where climbers have had to compete with each for space on narrow and steep climbs. 2019 saw more permits from Nepal than any prior year it is true but only a small scale as it had been rising each year. in 2017 permits issued totaled 373, in 2019 the total Nepal permits were 381.

In 2012, German climber Ralf Dujmovits snapped the shot of a long line of climbers snaking in what was described as a snake of non-moving climbers, similar to the 2019 photograph, how many permits in the year of noted crowding? Nepal issued 225 permits to foreign climbers. So clearly crowding impact depends on multiple other issues. What also made 2019 crowding somewhat worse was Nepal’s decision to honor past permits which swelled 2019 numbers on mountain past permitted number of population of 381 climbers.

In 2018 the scandal of faked permits came to light. how long this may have been going on and how much it contributed to further crowding is not quite clear. Under some conditions, crowds or other causes of slowing can create bottlenecks at critical points in these extremely high altitude death zones. Such climbers cause themselves and other climbers to have dangerously prolonged exposure to extremely high altitude further increasing grim altitude risk.

However, in spite of headlines declaring this a new problem, it is not. Nor is it the major cause of deaths. Making wrong decisions, not having set calls ahead of time in the face of high altitude cognition loss and the ravages on the body, those are the same grim causes as always. Even some of the traumatic deaths incurred such as falls can be laid at the feet of altitude illness. falls are more likely in the oxygen-starved 'stumbling' brain left too long in the death zone. Some have been trying to sound the alarm for years. First remarked in 1996, one hopes the pattern, understood at least since 2011, is finally being recognized. Overcrowding needs to be planned for under certain conditions of limited ascent hours and other possibilities.

Climbers and Sherpas might also get trapped in subsequent storms or run the risk of avalanche, severe temperature drops or extreme storms. Imagine these further delays in extremely low oxygen settings. In prior years, where overcrowding and inexperience also showed limited mobility, data confirms climbers descending without any reserves; stopping to ”rest” and never getting up again. From summiting Mount Everest, after a prolonged delay and not recognizing the dangers as they slowly trudged up with only the goal to summit before them. Years of this data, of death due to being slowed down in a death zone. Summiting, descending, pausing, and then death. How has the calculation of this possibility not sunken deeper into the list of ways the mountain can kill?

A study released in December 2008, "Why Climbers Die On Mount Everest" by Massachusetts General Hospital. "Factors most associated with the risk of death were excessive fatigue, a tendency to fall behind other climbers and arriving at the summit later in the day. Many of those who died developed symptoms such as confusion, a loss of physical coordination and unconsciousness, which suggest high-altitude cerebral edema, a swelling of the brain that results from leakage of cerebral blood vessels. Symptoms of high-altitude pulmonary edema, which is involved in most high-altitude-related deaths, were surprisingly rare."Among climbers who died higher than 8,000 meters above sea level, 56 percent succumbed on their descent from the summit and 17 percent died after turning back. Only 15 percent died on the way up or before leaving the final camp.

Yet, there is an even larger message here. You do not need to be in the high death zone of extreme altitude. Attempting 8000 meter plus peaks may not be in your glory dreams, understanding the risks of altitude may save you more than you might imagine. Broader truths have a way of doing that. Consider how the recent sad deaths of the 11 people on Mount Everest this spring 2019, seemed to focus on what has long been available, and review of eyewitness accounts of previous overcrowding complaints over the years all advance understanding that indeed an Everest climber should be well appraised of how best to alter plans and stay safe given what has been known for many years about excessive permits and high altitude illnesses.

The Matterhorn faced similar problems with overcrowding. Though a much lower peak at 14,692 feet over 500 people had died on this mountain over the years; so many that the Matterhorn has its own graveyard. Too many climbers were adding stress points that elevated risks and contributed to fatalities. In the 1990s yearly death rates were at (or exceeded) exceeding 24 deaths annually. many steps were instituted, and have had to be reimplemented again in 2015 and beyond but improved safety and reduced causality has been the result.

Nepal has not, so far, chosen to reduce the number of permits. in a country of such poverty where a single permit costs 11,000 dollars once can imagine the conflicts of interest and need. Add to that the infiltration of scam permits, how difficult it has been for Sherpas and other indigenous people to receive appropriate funds, respect, and expectations, and climbing on Everest remains problematic. The climber, as always then must consider more deeply what should he decide while still possessing the capacity for sound reason?

Grueling and unforgiving are likely the kindest words one could say about Everest and altitude in general. Other climbers have barely escaped alive, suffering grievous effects from frostbite, heart attack, retinal and brain hemorrhage. Summiting 29,000 feet even with pressurized oxygen, is to climb into a death zone. Elevations above 25,000 feet are heights at which the body simply cannot sustain itself and begins to break down and fall apart. The majority of deaths for climbers occur during descent. Protecting remaining mental and physical assets then is of paramount importance. Some post-summit trauma is also due to extreme fatigue with unsteadiness, poor judgment contributing to falls and other injury. The climber may have slipped on the ladder, gone into a crevice but it was too many hours awaiting his turn to the summit that killed him or her. making the poor choice to pursue past all hours even when time was slipping away, afternoon closing in. that was when death was sliding in; it had only not yet pounced. Later, as the climber struggled down, weary beyond thought, legs ataxic, death arrived with a fall but it was only death delayed. The fatality, the slip, the stumble, the crash was already written and waiting. If you use all your fuel and courage going up, you crash and abandon your own body in the attempt to get down. if you have ever made the more forgiving error of hiking or running through all your strength and then, belatedly, having to drag yourself back on breath and steam itself, you will know how easy it is to burn all in a fevered thrill of a dream, of a summit push. the experienced climber does not betray his body and has safeguards to prevent this in place. We know how common it is more climbers to meet their end on the descent; dramatically witnessed wherever humans seek the highest peaks. K2 is well known as a mountain that, even if you make it to the top, will likely kill you before you make it safely back down. One in four climbers who successfully summit K2 will not survive the descent. Everest, the world's highest peak at 29,029 feet, has a very favorable fatality rate of somewhere close to 6 percent. Annapurna, in central Nepal, is a far more dangerous mountain to climb, with a fatality rate of over 38 percent. Annapurna rises to 26,545 feet and is the 10th highest peak in the world. For every three climbers who summit, one person dies. The ratio is about 34-38 deaths per 100 safe returns on Annapurna.

K2 (Chhogori) is also known as the Savage Mountain, on the Pakistan-China border. It is the world's second highest peak at an altitude of 28,251 feet and second only to Everest in height being only 777 feet shorter than Everest. Yet K2 is far more perilous and deadly to climb with 1 in 4 climbers perishing at a death rate of 30 percent.

This year, 2019, Naga Parbat took two beloved climbers onto its slope and ended both their lives. Tom Ballard died alongside his friend Italian climber Daniele Nardi on Naga Parbat. There, in the Pakistan Himalayas, Tom died, not terribly far from where his own mother, Alison Hargreaves, sleeps forever on the slope of K2 where she perished in 1995. Tom Ballard was but a small boy when she left first to successfully summit Everest and then to try K2. Naga Parbat is still considered the third most dangerous 8,000-meter peak after Annapurna and K2. Prior to 1990, Nanga Parbat had an astonishing death rate of 77 percent. While the odds are better now, they did not allow Alison Hargreaves son to escape the fate of so many on these treacherous peaks. Two generations, mother and son, killed by two ferocious mountains. 

The United States has two deadly mountains of its own in Denali and Mt Washington. Terrible winds, unstable weather are two of the reasons these mountains have such a dangerous reputation.

Altitude is ruthless. Altitude kills, and it does so no matter your fitness or fame. The losses on Everest each year are mind-numbing and so grievous. We hear of them and are stunned. We should be just as tormented by the deaths that go unheralded. The skier, the hiker, the trekker. Deaths occurring at much lower altitude in the young, the novice, the experienced, the happy couple, the solo tourist, the young man away for a quick weekend, the teenager seeing the upper forest for the first time. Anyone, everyone bears a risk. No one is exempt and yet, all--from the marvelously fit (especially the fit it turns out) to the couch potato sort, we all have the danger that took the lives of those Everest climbers. That is not the most vital message. This is: No one need die of High Altitude Illness. The tragedy is High Altitude death is avoidable. Don't be a victim. Do not die while surrounded by the beauty of the high hills.

There are also tales of astonishing survival in these against all odds. I had the privilege to be acquainted with Lincoln Hall, an Australian who summited Everest in May of 2004, after a failed attempt in 1984. Lincoln returned to summit Everest in 2006. In that attempt, Lincoln reached his goal but suffered High Altitude Cerebral Edema, became disoriented and was acting irrationally. The Sherpas with him struggled to bring him down but eventually, they became exhausted themselves. When Lincoln collapsed, at last, the Sherpas radioed in with the terrible news that Lincoln appeared to have no vital signs. His grieved friends back at camp asked only that the Sherpas please raise a cairn of stone. There were no stones at that spot so the exhausted Sherpas left Lincoln rest as he was in silent and frozen death. His wife was radioed and told he had passed on. Or so it seemed. Lincoln Hall, left for dead at an elevation of over 26,000 feet for 12 hours in the killing zone where oxygen is too thin to keep anyone living and where cold murders anyone who dares stay long even with an oxygen tank... through a dark night, Lincoln Hall lay where he had fallen. And so, as the next team summited in the morning, they came upon the most unexpected sight. That team, a party of four climbers, Dan Mazur, Andrew Brash, Myles Osborne, and Jangbu Sherpa spotted a man perched in the dawn light, atop the 3,000-foot Kangshung Face. Lincoln sat on this 3,000-foot cliff, which looks down over the entire Tibetan Valley; this man, terribly frostbitten somehow alive, turned to them and said, "I imagine you're surprised to see me here." The climbing team abandoned their own dreams of ascent to bring Lincoln back down to camp.

Mr. Hall taught me, besides something of climbing, and a nickname I shall not reveal--he spoke most of the need for careful judgment. He had turned back on an earlier 1984 ascent try. Lincoln Hall was the rarest of men. he died from the cruelest fate at the age of 56 years from, of all things, mesothelioma. He had been exposed through inhaled asbestos fibers incurred while building cubby houses with his father in the early 1960's. Before he died, Lincoln Hall strove to educate others about the insidious dangers of altitude illness, especially High Altitude Cerebral Edema. He survived this condition which claims over 50 percent of its victims but the coma he was in and the frostbite it caused as he lay in the extreme cold, resulted in him losing a toe and the tips of eight fingers.

Lack of oxygen robs the brain of sound judgment and the ability to react with speed or agility. At such altitude, the body is burning itself up. Everyone is coughing, unable to consume adequate calories, sleep is impossible; it is if everyone is slowly dying while at this extreme high altitude. At Everest, once at the death zone, it is vital to begin to summit, or begin to get the heck down to where the body can begin to heal from such punishment. Recent congestion and a relatively new phenomenon of inexperienced climbers buying into Everest as permits are available to any buyer heighten this deadly traffic jam. Crowds slowing movement make the death zone slow further. Altitude kills when trapped at these heights. But climbers know this yet are greedy to the summit. What is worth the price of risking death? No one need die from Altitude illnesses. Not even the famous and certainly not you. Not if you are wise and well informed.

What is Good About Altitude?

While so very few will ever come upon the extreme high-altitude rigors of Mt. Everest, there are dangers and lessons of high altitude which resonate for many even at lower altitudes of 8000-10,000 feet. Research has long noted those at higher elevation have less incidence of obesity, less incidence of Type II diabetes and heart disease. Colorado had a 19.8 percent obesity rate, the second lowest in the country.

Many studies suggest those living long term at high elevation have much lower cardiovascular mortality. However, simply moving to an elevated lifestyle is unlikely to change your own heart risk. Moving late in life to altitude can sometimes increase heart risk in some. Unfair, isn't it?

Sometimes, when the elderly move from sea level to the long-term high altitude they increase their risk of certain conditions. Though this piece principally concerns acute altitude illnesses, let's spend a few minutes on the peculiarities of the benefits of long term

Why is this? The reasons are complex. Those already living at elevation may come from a certain genetic group. Scientists note many living at altitude for a long period adopt a very active lifestyle. Is it then the altitude or the exercise? Likely both. Other data shows those living an entire lifetime at altitude have gradual accumulated exposure to high levels of UV radiation. Ultraviolet radiation increases by about 10 percent with every 300 m increase in altitude and may profoundly influence cardiovascular mortality. Protective effects of ultraviolet radiation are mediated by the higher concentrations of Vitamin D, probably by reducing the risk of thrombus formation. The increased cardiovascular and cerebrovascular risk may result from Vitamin D deficiency due to the related increase in parathyroid hormone, which increases insulin resistance and is associated with diabetes, hypertension, and inflammation. Another impact that could take a lifetime to benefit is reduced air pollution. Decreasing air pollution with increasing altitude may represent another potential contributing factor to the CHD mortality reduction. The relationship between exposure to air pollution (short- and long-term) and cardiovascular events has been demonstrated by epidemiological studies. Mechanisms may include enhanced coagulation (thrombosis), acute vasoconstriction, a propensity for arrhythmias, and systemic inflammatory responses promoting progression of atherosclerosis. Elderly moving from sea level to altitude though run the risk of higher rates of pulmonary hypertension, increased respiratory infections and emphysema rates. All those newly arrives and those long-established have a higher incidence of skin cancers.

The irony of altitude is that regular life at altitude, once adjusted to it--is actually probably HEALTHIER at reasonably high altitude. Life spans may be longer. Many studies seem to bear this out. But we must leave all this tantalizing research behind and focus on only one aspect. What happens when we take a human from low altitude and thrust him in those first few days up to his altitude? What are the major risks and dangers? Therefore, when speaking of high-altitude risks, we are describing, sudden new movement from low (e.g sea level) to new high altitude (e.g 8,000 feet). How can we make anyone better aware of the risk of progression from mild acute mountain sickness to cerebral edema and, gosh forbid death and how to avoid death in every single person? Why do so many fail to heed the warning signs that could have spared them?

I work in the field of wilderness medicine, and I am often contacted regarding the use of medications for those traveling to high-altitude. I spend most of my time being sure to teach about the various forms of altitude sickness. Some people may call in prior to travel from Seattle to a ski vacation in the mountains of Colorado or before flying to Cusco at an altitude of 11,200 feet.

The mountains have a beauty and attraction that is undeniable to so many of us. Some travel to the higher peaks of Colorado to ski and hike. Others trek the trails of Machu Picchu or scale other technical climbs solo or with teams of friends. We all have our private reasons. The tragedy though of reading about, not only the deaths of those near the pinnacle at Everest of hikers in Colorado --unexpectedly and unaware-- that altitude too would be their death. To learn of an acquaintance who refused a call, assured everyone that being such a great runner, Cuzco would not be a challenge. At age 27 years, the details never made it back but he died of an altitude illness that never should have felled him. Altitude illnesses go by this dangerous common grouping in which one form, is mild and reversible as long as one treats acute mountain sickness with respect. For some reason, the most serious forms of altitude sickness are not well known among many. My job in wilderness medicine is NOT to just cheerfully hand out Diamox and other medicines--though of course, I DO. It is to also keep people alive in truth. I hope you take the time to read this dreadfully long piece and share the details herein. Learning the more serious forms of High-Altitude Illnesses may save your life and another person, even those you love.

If You Read Nothing Else Read This!

Yes, mild altitude sickness is rather frequent if you travel to altitude. At least 25 percent of those will complain of headache, some nausea, and hangover symptoms w/in 4-6 hours if arriving suddenly at 8,500 feet from sea level. At higher altitude, it will strike up to 85 percent. Taking Diamox also known as Acetazolamide is effective at prevention--up to 75 percent effective in some studies. Less so for those going abruptly and quickly up Kilimanjaro. The benefits against such profound altitude is less impressive.

  Other medicines such as steroids (Dexamethasone) are helpful but are not routinely advised. Many other medicines have been reviewed, including higher dose Ibuprofen at 600 mg three times a day. Gingko Balboa studies are not conclusive, nor can one make conclusions regarding Gingko Balboa. This is not a medicine review, this is a RISK review. As such I will not review HAPE and HACE medications such as

 The trap, the worry, the tragedy is this: these very symptoms of nausea, headache, loss of appetite, crankiness, and fatigue are not merely trivial symptoms to be medicated and pushed through. They are also red flag warnings to be analyzed, carefully considered before any progression. Not enough is said about the truth: if one ignores such symptoms carelessly, one risks enacting a chain of events in the body and precipitating serious sequelae that can lead to brain, cardiac, pulmonary injury, consequences, and death. Death? Excuse me: Yes...To your death. The symptoms ignored may have been an alert of impending high altitude cerebral edema or high altitude pulmonary edema. Consider how it is often the young fit male who pushes himself is the one who often risks and dies at extreme altitude.

If you read only one piece of this, remember this part above. Altitude illness is often the hangover symptoms commonly noted in the first 4-6 hours and extending up to the first 2 days upon arrival at high elevation. That does not give you carte blanche to assume, "Oh well, mountain sickness...tough it out, keep going..” Think and note if you (or the person you are observing is getting better as they should? If you (or the person observed) is NOT improving, DO something. Go down in altitude, seek medical advice, keep reading. Just do NOT ignore. Bad things happen.

The other mistake is assuming symptoms which arise more than two days after arrival at elevation simply must be acute mountain sickness. This is not altitude illness until proven otherwise. Normally by 48 hours, the human body has been working hard to make physiologic adjustments as you will see below. The kidneys are making acid-base changes in conjunction with your lungs. The bone marrow is hard at work creating more red blood cells pushed along as it too works with the kidneys. The kidneys you see do so much more than just filter your blood and release urine. Kidneys are amazing; these master manipulators, paired organs in your body are also secreting--among other chemicals, erythropoietin [EPO], a chemical that encourages more oxygen-carrying red cells. The kidneys also determine how much sodium, acid, bicarb (base) the bloodstream should hang on to as it adjusts to the rate of your breathing and how much carbon dioxide your lungs are blowing off as you pant in the thin air of high elevation

Telling yourself to ignore body signals of stress and pushing through either early altitude symptoms OR late NON-altitude symptoms are both risky patterns and not a good idea at all!.

The value of reading what is detailed below is that if you are planning on traveling to high altitude in the future you may be surprised whose life you save.

Acute Mountain Sickness on Jets, Really?

Yes, those susceptible can develop symptoms of acute mountain sickness in modern pressurized jet cabins where air pressure is kept at about 5,000 to 10,000 feet equivalency. Some actually will develop mild headache, nausea, loss of appetite and you thought it was simply that you didn't like flying? This non-sea level status of oxygen pressure is why those with significant lung disease may need to carry oxygen with them. it is also why you may notice your sleep apnea is more pronounced on board a long flight. While such mild "elevation" equivalent aboard a jet is VERY UNLIKELY to develop into a serious form of altitude illness it does show you altitude issues matter and more often than you might guess!

Altitude in Real Life More Commonly

In major skiing locales in the United States, serious forms of altitude illness are generally recognized, and emergency treatments promptly instituted, though sometimes the ill have retreated to a hotel room, unaware how ill they actually are becoming, especially in regions such as Colorado where skiers arrive in winter regularly. This can be serious and has been fatal. People have died while hiking in the USA while ascending rapidly in our own mountains at higher altitudes in more remote settings. Risks increase internationally, especially where tourists are not watched so protectively. So much is accessible and many travel now to South America and visit in high altitudes of Peru or Ecuador. Others consider Kilimanjaro which requires no extreme climbing skill; never considering altitude risks.

My Own Foolish Experiences

I misunderstood high altitude problems when I began hiking as a teenager at elevations over 16,000 feet. Like many I meet now, I incorrectly believed altitude illness to be only a matter of terrible inconvenience. Even, later on during one memorable rapid rescue mission, I was enlisted for in which I developed a case of pulmonary edema I told no one. Still stubbornly, believing altitude to be nothing more than a terrible inconvenience. Such a notion is a grave mistake, one often fatal. Altitude can kill you if you assume this. Altitude is NOT simply a problem to be surmounted by training and preparation, or some perfect combination of medicines. Nothing can save you from the worst forms of altitude illness, nothing but being taken down the mountain before you die. Misunderstanding this, or being unaware of the graver forms of this illness, a mulish belief that toughness prevails, that is the tragedy that befalls those on Everest and it also kills others everywhere.

It doesn’t help that all forms of altitude sickness, the milder and the deadly, bear similar names. The common habit of causally naming all variations of ailments brought on by high elevation as “Altitude Illness,” even the forms that are terribly fatal, such informality is unfortunate. Neither you nor I was in charge of naming these ailments but what can we do now? Just this: don't let the unimaginative naming be the reason you or someone you can know confuse the vital information below. Unimaginative naming should never be a reason for people to die in ignorance on some high elevation saying "Wait, all altitude illnesses are not the same?!" They are NOT and need different response and attention. One can overlap into another meaning all symptoms bear close attention. Good, now you already know what took me absurd years to grasp.

Because, even now, on mountains, ignorant of warning symptoms of dangerous altitude illnesses, people die without ever being alerted to signs that should have saved their life. This article may raise your odds tremendously. Just knowing you may be at risk is the first step. Many believe being fit, and trained, means they needn't even worry about altitude illness. Wrong. Please show them and call them back to read!If we don't give ourselves a chance to become educated, to accept our prior beliefs were false, we can't save ourselves. We can't help anyone.

In the United States, serious forms of altitude illness are often recognized in emergency treatments instituted. people have lost their lives from altitude illnesses in skiing, hiking, and climbing. Almost all these deaths were avoidable. Risks increase internationally. This is because of increased altitude, far-flung locales, language barriers, and more limited access to emergency medical care. So many beautiful regions in the world are now accessible. Vacationers and trekkers in international locales such as the Alps, in Peru, Ecuador, or Kilimanjaro due not realizing basic altitude knowledge would save them a terrible and unexpected death far away from those they love.

At sea level, we live under a blanket of air which presses against us. Many do not realize, but it is this pressure that forces air into our lungs not simply air density itself, that allows for air exchange into our bodies and blood stream. At sea level, because air is compressible, the weight of all that air above us compresses the air about us, making it denser. As you travel up in elevation, the air becomes less compressed and is therefore “thinner.” This effect can be felt as early as 5,000 feet in those who are susceptible; more often above 8000 feet. This is what makes everyone connected in a way you will see to the losses of these elite dedicated climbers which, at first view, may seem disconnected from your own life.

What Causes Altitude Illness? All about Oxygen Spacing

Altitude illnesses are caused by the failure of the body to adapt quickly enough to the reduced oxygen at increased altitudes. At higher altitude, oxygen molecules are spaced further apart in the atmosphere. Barometric pressure drops, the higher one climbs. As this pressure falls, oxygen molecules are less closely bound and slide further apart.

Air is made up of nitrogen, oxygen, and argon with traces of other stuff in it. Nitrogen is about 78 percent, oxygen is 21percent, and argon is 1 percent, those percentages stay constant no matter what the elevation.

At sea level, the concentration of oxygen is around 21 percent, the barometric pressure averages 760 millimeters of mercury. At Everest base camp, at 17,600 feet oxygen molecule concentration is already only at 50 percent of sea level. At Everest’s peak at 29,029 feet, the oxygen saturation—or effective oxygen- the oxygen concentration is only at 33 percent of sea level.

Higher altitudes don’t alter the atmospheric O2 concentration. However, it does decrease the number of oxygen molecules per breath. When you climb in altitude you move from 21 percent concentration to lower and lower percent concentrations as lower air pressures let the oxygen molecules drift apart.

At Everest Base Camp on the Khumbu Glacier, which lies at an altitude of 17,600 feet (5,400 meters), oxygen levels are at about 50 percent of what they are at sea level. That drops to one-third at Everest's summit,

ALTITUDE RISKS CONSIDERATIONS

1.    Those who are physically fit are as equally at risk as anyone else.

2.    Those over 50 years of age may have a slightly decreased risk.

3.    The risk may be higher if you are extremely active on your 1st day at altitude. Intense exercise can accelerate the forces described below.

4.    Rapid Great Height: Any person ascending 3500 meters (11,5000 feet) in one day is at high risk. For this reason, a plane flight inbound to high elevation is a common high risk.

5.    Rapid height compounded with sleeping high: Any person ascending more than 500 meters a day and sleeping at height if above 10,000 ft without time to acclimatize [So called "sleeping high"]

6.    Certain genetic linkages make people more susceptible. Two genes identified in Chronic mountain sickness include: ANP32D and SENP1

7.    Individuals who have previously had altitude illnesses are more at risk when they return to high elevations: a) Prior history altitude illness and ascending 9,000 feet in a single day b) Any person with a history of high-altitude cerebral edema is at risk at abrupt altitude in general.

8.    Children do not have a higher risk, but it may be difficult to recognize symptoms in very young children.

9.    Any person with current respiratory illness or other health problem making it hard to breathe normally are at higher risk.

10. Use of alcohol may increase risk.

11. Dehydration may increase risk HOWEVER drinking extra fluid does not prevent acute altitude sickness and too much water may upset your normal salts. Hyponatremia carries its own risks.

12. Use of Diamox/ acetazolamide used as a preventative does not mask more serious altitude illness. Therefore, the use of Diamox does NOT increase the risk for serious forms of altitude illness.

13. Dexamethasone (4 mg 2-3 times a day) started before ascent can also prevent high-altitude pulmonary edema, as well as cerebral edema and mountain sickness, it can cause abnormal mood swings in some and therefore has more risk than Diamox/ acetazolamide.

GOLDEN RULES

I.    If you feel unwell, you have altitude sickness until proven otherwise.

II.    Do not ascend further if you have symptoms of altitude sickness.

III.    If you are getting worse then descend immediately. 

What Elevations Matter?

Altitude sickness can occur in some people as low as 5,000 feet but grave symptoms do not usually occur until over 10,000 feet. Still, dangerous and potentially fatal forms of altitude illness have occurred in those at relatively low elevations. Even if traveling to 6,000 feet one should be aware of all forms of this condition.

What is Occurring in the Body?

You naturally feel breathless at higher altitude—this is NORMAL. You will take more frequent breaths to get enough oxygen, especially if you are very active right away. Your body hyperventilates to perform this feat, the lungs blow off carbon dioxide and the acid-base balance in the bloodstream changes. Given a few days (normally about 48-72 hours), the kidneys can rebalance the disturbed acid-base balance in your bloodstream but this takes time. If you do not have the option of gradually ascending then the altered acid-base status creates problems in the body. In addition to altered blood acidity levels, the body is trying to adapt to changed lung pressure, electrolyte levels, and fluid and salt balance too. The blood vessels in the brain distend to absorb more oxygen. While we know everyone at altitude likely has some brain swelling, only SOME get more dramatic swelling –the reason why remains unclear.

In addition to swelling, small vessels in the brain may leak, and all of this will most likely cause migraine-like headache in acute mountain sickness. (Migraine and AMS are NOT identical, however) Acute Mountain Sickness and its nauseating headache can go on to the very dangerous high-altitude cerebral edema. This likely occurs as swelling progresses and pressures increase.

The etiology of high-altitude pulmonary edema is an example of when the lung is starved of oxygen. How this 1st progresses is not exactly known. We do know however that as the lungs sense low oxygen and blood vessels constrict, damaging substances are released which have the inadvertent effect of creating inflammatory fluid release. These initially, very small fluid pockets in the lung arise, further impairing oxygenation. These, in turn, create inadequate regions of lung circulation. As the lungs sense regions of poor oxygen exchange and circulation, they shut these regions down causing further swelling and problematic perfusion. If uninterrupted by rescue to a lower altitude, this confused feedback loop becomes a devastating downward spiral as greater regions of pulmonary dysfunction occur resulting in fluid flooding the lungs and an inability to exchange oxygen with the bloodstream.

A similar effect may be the cause of high-altitude cerebral edema. When the brain tissue is exposed to variable oxygen, small vessels may respond with spasm or a similar release of chemical agents which can cause fluid release through inflammation and small vessel damage. This may be the reason postulated for increased cerebral pressure, and the concept of mild brain swelling. In either condition of pulmonary or cerebral edema, the failure to get the victim down to lower altitude will likely result in progression and death. When we, as rescuers, are trapped on the mountain with such an ill individual, our only other recourse our emergency measures to reduce edema with medications and to artificially provide oxygenation and atmospheric pressure with rescue devices. These are extreme measures and you can prevent yourself from such a critical situation by recognizing symptoms and yourself or others that suggest crossing over from acute mountain sickness into more serious possibilities. These are described below. You can, under certain situations, also give your body advantages to adjust to the altitude more gradually.

At very high altitude, such as over 21,000 feet, there is no acclimatization, only debilitation. In such a prolonged oxygen-deprived atmosphere, working to capacity, lactic acid, and other waste products build up in the muscles, which produce weakness and fatigue. Humans are not meant to live in such conditions.

Sleeping at Altitude

Many believe that altitude symptoms are intensified if rapid ascend is compounded with sleeping at high-altitude as well. This is given rise to the notion of “Climb high, sleep low”

Mountaineers at very high altitude have a long had an eerie observation of fellow tent mates breathing erratically and slowly in sleep. Many suspect early in extreme high-altitude defect of increased breathing rate and loss of carbon dioxide, as a result, creates an increased base versus acid state in the body. At night with the loss of carbon dioxide/ acid drive, the brain responds with a type of central sleep apnea. Further studies have shown complex sleep patterns and the physiology remains to be clear but overall early extreme high-altitude sleep combined with rapid ascend contributes to difficulty in the body making quick adjustments. It is for this reason that sleeping combined with rapid ascend creates additional altitude illness risks. Those who already have sleep apnea, obstructive or central, need to be aware this may be compounded at high altitude.

Forms of Altitude Illness

There are three main types of high-altitude illness. There are methods and techniques to reduce the risk of all three forms. Knowledge of potential symptoms and signs and awareness of yourself and possible traveling companions are vital. Paramount is the understanding that potential high-altitude pulmonary edema or high-altitude cerebral edema needs immediate attention to do its potential fatal nature.

 1)Acute Mountain Sickness: This is the most common form of the condition. It is often mild and short-term.

 2) High Altitude Pulmonary Edema (HAPE): This condition causes your lungs to swell with fluid, which can be fatal. More likely to occur at extremely high altitudes over 12,000 feet.

3)High Altitude Cerebral Edema (HACE): This condition causes your brain to swell with fluid, which can be fatal. Like HAPE this is most often seen at very high altitude but can occasionally occur at lower elevations.

There are three main types of high-altitude illness. There are methods and techniques to reduce the risk of all three forms. Knowledge of potential symptoms and signs and awareness of yourself and possible traveling companions are vital. Paramount is the understanding that potential high-altitude pulmonary edema or high-altitude cerebral edema needs immediate attention to do its potentially fatal nature.

Symptoms of the Major Forms High Altitude Illness

Acute Mountain Sickness (AMS)

AMS is very common at high altitude. Acute mountain sickness goes by many names, in South America, it is called “Soroche” and some people, unfortunately, believe all altitude illnesses are no more serious than acute mountain sickness. This sickness can progress into cerebral edema which is a medical emergency and requires evacuation to lower altitude. There are other medical maneuvers that can be used additionally if this illness progresses but they are not to be used with the notion of continuing climbing or ongoing travel. This is not a discussion of emergency measures for the treatment of HAPE or HACE, except in passing. The major thrust of this discussion is an awareness that some forms of altitude sickness are extreme, dangerous and how to recognize such a progression.

Mild acute mountain sickness may feel as though you have a case of early flu with simply feeling generally unwell. Often you will notice a pounding type headache (headache is not always present), loss of appetite, queasiness, weariness or fatigue, shortness of breath with exertion, poor sleep, and the occasional feeling of dizziness. Acute mountain sickness occurs anywhere from 2-24 hours after arriving at altitude. Symptoms that suddenly appear after someone has been well for at least 48 hours at altitude should not be ascribed to acute mountain sickness. In such a case where a person has been well and not been experiencing early symptoms--always look for another cause for delayed unusual changes.

If you are curious, there is a diagnostic score sheet for acute mountain sickness called “The Lake Louise Score” but this is principally for research purposes. The intent is to look for symptoms as described above within two days of arrival. The worry is to always consider whether a person may be developing more serious altitude illness.

Worrisome signs for more moderate to severe mountain sickness include any difficulty walking, slowed thinking or confusion, sluggishness, increased headache, or vomiting. Any of these are suggestive that cerebral edema may have begun. If you are observing another, we often suggest asking that person to walk several steps to see if their gait is steady and firm. If it is not, or if they have difficulty comprehending your request, or seem very withdrawn or otherwise acting abnormally; this has gone beyond what you might expect of acute mountain sickness and needs rapid attention.

Can I Avoid Mild Mountain Sickness?

The best way to reduce your chances of mild mountain sickness is very slow ascent which allows your body to adjust naturally.

We also advise avoiding alcohol the 1st night at high-altitude. Alcohol seems to complicate the body’s adjustment. The mechanism may involve the way in which alcohol interferes with normal sleep. For this reason, it may be wise to avoid all sleeping agents which may also act to suppress oxygen levels in the blood as you sleep.

Avoiding overexertion, the 1st few days of your arrival at altitude.

Since about nutrition and fluids are advisable. However myths about ingesting large quantities of water are not smart, nor have they been born out.

Medication: Diamox is not a replacement for this good advice but is helpful for many as a preventative. Diamox is a mild diuretic and is a sulfa-based medication (can often be used even in those who are sulfa allergic) which asked by speeding the body’s acid-base processing at the kidney level. If started 24 hours prior to arrival to altitude and continued the first 2 days at altitude, Diamox has been found to be overall at least 75 percent effective in preventing Acute Mountain Sickness.

How exactly acetazolamide increases minute ventilation, improves arterial blood gases, possibly decreases the production of cerebrospinal fluid, and reduces the symptoms of AMS remain poorly understood. The drug is a carbonic anhydrase inhibitor that causes a bicarbonate diuresis, resulting in metabolic acidosis. This bicarbonaturia ultimately lowers the cerebral spinal fluid (CSF) bicarbonate concentration, thereby lowering the CSF pH and stimulating ventilation. Membrane-bound carbonic anhydrase isoenzymes are present on the luminal side of almost all capillary beds including the brain and can be inhibited by low doses of acetazolamide leading to local tissue retention of CO2 in the order of 1–2 milliliters Mercury.

The most common side-effects of acetazolamide are digit and lip tingling, change in taste of carbonated beverages and occasionally vision changes and loss of appetite and nausea.

Persistent Mild Acute Mountain Sickness Treatment

If your symptoms remain mild the first two days in spite of the use of Diamox, and limited activity which should you next consider?

• Most importantly, NEVER go to a higher altitude if you have AMS.
• If at all possible, descend to a lower altitude and continue rest at a minimum. Descent to 1000 feet lower generally suffices.
• If you have been taking a dose of Diamox at 125 mg every 12 hours. Depending on symptoms, the dose sometimes increased to 250 mg twice a day. However, this also increases the side effects of tingling in digits. nausea, fatigue This medicine also increases sunburn risk. It IS a mild diuretic. Odd side effect: Makes soda pop taste flat
• Under doctor’s supervision or discussion, other interventions include use of dexamethasone and/or oxygen.
• The headache of AMS improves with rest and with medications such as ibuprofen (Motrin) or acetaminophen. The use of ibuprofen itself has been studied to reduce acute mountain sickness but the dose required is at 600 milligrams every eight hours and the benefit is preventive/ prophylactic.
• If symptoms have persisted into the third day, seek evaluation and alternative or secondary diagnosis. e.g dehydration, hypothermia, other. Do not force plain water. Hyponatremia is a risk
• Seek immediate evaluation if any of the following symptoms below.

Acute Mountain Sickness can be a warning sign and progress to high high-altitude pulmonary edema or high-altitude cerebral edema. These latter two conditions--- HAPE and HACE---can be fatal within hours.

HAPE [High Altitude Pulmonary Edema]

No one can predict who will get HAPE. There are, however, known risk factors. Your risk for HAPE increases with the following:

• A fast rate of ascent and the altitude attained. The incidence of HAPE is 1 in 7 people in those climbing to 18,000 ft in 2 days, only 1 in 50 who take 7 days, and 1in 500 who climb to only 14,000 feet in 4 days.
• Vigorous exercise
• Some evidence reported those with chest infections or even common cold before an ascent at higher risk
• There is also a genetic component thus positive family history of other family members w/ HAPE may increase your risk.

Symptoms of HAPE Note Again: Impact of gradual ascent reduces the incidence profoundly

1. Incidence: 1 of 7 people climbing to 18,000 feet in 2 days, only 1 in 50 who take 7 days, and 1 in 500 who climb to only 14,000 feet in 4 days.
2. Shortness of breath at rest if present is HAPE till proven otherwise
3. Normally begins at least 2 days after arrival at elevation (are exceptions
4. Wet cough
5. Chest tightness
6. Wheezing
7. Fever
8. Rapid heart rate
9. Bloody or frothy sputum
10. TREATMENT: DESCEND Immediately, pressurized Gamow bag, O2, nifedipine, phosphodiesterase-5 inhibitors (sildenafil, tadalafil, vardenafil

Always be alert to shortness of breath at rest. It is never normal for yourself or a traveling companion to be breathless while at rest even on the summit of the tallest mountain. If this symptom appears, take it as a sign of probable HAPE --and treated with its serious fatal hazard. Those that have ignored this symptom have died.

Symptoms include wet cough, fever, frothy spit, rapid heart rate, bringing up bloody sputum. Another symptom’s survivors have described include a feeling of impending suffocation at night when trying to lay down or rest. Some have had such severe oxygen deprivation from the pulmonary edema, they may become confused or combative. This form of pulmonary edema may begin shortly upon arrival at high-altitude or, more typically, 2-3 days later. Often times, the affected person will be noticed to be more breathless than all those around him, certainly with exertion but also at rest which is the key indicator.

Most of those who have pulmonary edema will continue to be suffering from additional symptoms of acute mountain sickness. On top of the symptoms of acute mountain sickness, they will develop a progressive cough which gets worse, wet sputum with pink or white frothy results. Heart rate may be very fast, the lips may turn blue. They are often so breathless they are unable to take in any food or fluids. Many people confuse this condition with a chest infection but if you are at altitude you must always consider this first and immediately get down to lower altitude and seek medical care. As rescuers, we provide extra oxygen and/or increase the air pressure around a victim with a Gamow bag in an effort to reverse the underlying cause of HAPE which is a lack of oxygen, but these measures are our only used as temporary substitutes to getting someone rapidly down the mountain. In addition, you may see, under emergency conditions certain medicines used by trained doctors. Those might include Nifedipine, a drug to open up the blood vessels in the lungs and reduce the high pressure in pulmonary vessels. Another medicine also used includes Sildenafil (Viagra), that works by a different means to also open up the blood vessels in the lung. Dexamethasone, a medicine used for many treatments in altitude illnesses is often provided too but all of these drug treatments are used as a temporary measure; the successful treatment is descent.

 High Altitude Cerebral Edema (HACE)

This altitude illness, High Altitude Cerebral Edema, has a 50 percent mortality rate once, coma has occurred. Incidence is 1 out of 100 to 200 people after2 days after ascending past 13,100 - 16000 feet in 1 percent of people who ascend to heights of 10,000 feet or above get high-altitude cerebral edema. High-altitude cerebral edema has been seen in someone at an altitude of just under 7000 feet.

All of the same risk factors that contribute to acute mountain sickness or high-altitude pulmonary edema also increase the risk for this condition. Some researchers believe those more likely to get high-altitude cerebral edema are those who have continued to climb while enduring and ignoring acute mountain sickness. This makes it particularly important to be aware that acute mountain sickness is not a benign illness.

Ignoring Acute Mountain Sickness and continuing to ascend can be fatal. Moderate Mountain Sickness can progress to Cerebral Edema

Symptoms of HACE

1. Develops in those after 2 days at elevation
2. Headache (sometimes progressive or beyond the expected two days of AMS)
3.  Weakness
4.   Disorientation
5.  Loss of coordination
6. Decreasing levels of consciousness
7.  Loss of memory
8.   Hallucinations and Psychotic behavior
9.    Coma
10. TREAT by descending immediately, O2, Dexamethasone

High-altitude cerebral edema causes confusion, clumsiness, and/or stumbling. Some of the first signs may be odd or uncharacteristic behavior observed in your travel mate. People have described early signs including laziness, excessive dramatic emotion or even unexpected violence. Common signs include what appears to be a drunken stumble or difficulty walking a straight line. Drowsiness and loss of consciousness occur shortly before death.

Consider and Beware: Those who are affected by the above ailments may not realize that there is a problem! Be alert to potential danger signs in your companions and educate them so they can keep an eye out on you.

Other Forms of Altitude Illness

There are other types of high altitude dangers and illnesses beyond these major three. For example, sudden vision loss occurs due to High-Altitude Retinal Hemorrhage (HARH) which can cause eye damage. However, this article strives to remind readers that altitude sickness is not always being. It must be treated as a potentially progressive condition which can—if not heeded—lead to irreversible changes that require emergent action lest death occurs.

Mimics of Altitude Illness, or Worsen Altitude Risks AKA More Killers.

Finally, all hikers, skirts, climbers understand the many mimics of acute mountain sickness which can include hypothermia, dehydration, asthma, pneumonia, heart attack, hypoglycemia, and exhaustion. If you have been well and it has been over three days since you are at your final elevation, without troublesome headache, consider other serious conditions. Even the fittest climbers at Everest have died from hypothermia, unsuspected dehydration, and likely heart disease. In addition, as described above, many believe the person who insists on pushing through early mountain sickness is the same human who raises his risk for serious fatal forms of altitude illnesses. Cold, dehydration, lack of oxygen, fierce drive all serve to harm our best ability to use the reason that would keep us alive and allow us another day to climb again. Never keep going either out of the belief you might ruin the planned excursion for others. Bringing down a dead companion is not a kindness. Hiking, trekking, skiing, bouldering, climbing, technical climbs all are wonderful activities done in the most beautiful settings imaginable. Be sure you understand the varieties of challenges altitude presents to some of us so you may continue to enjoy the spiritual and physical joys of the hills for years to come.

SUMMARY

Remember! The best way to safeguard your health and avoid altitude illness is to move to high altitudes gradually, giving your body time to adjust and adapt to lower oxygen levels. This is especially critical for those living at sea level.

When planning to go above 8000 feet, you should try never to climb more than 1000 feet per day especially if you suspect you are developing altitude-related symptoms.

Most experts recommend prophylaxis with medications for travelers who plan an ascent from sea level to over 3000 meters (9840 feet) in one day, particularly for those with a history of acute mountain sickness. Both Acetazolamide and/or Dexamethasone starting 12-24 hours before high altitude exposure and continued three to four days prevent sickness.

Dexamethasone CAN cause troublesome side effects however including insomnia, mania, anger, rage reactions, irritability, loss of appetite, extreme hunger to name but a few. Test this and Diamox at sea level to be aware of any side effects and discuss thoroughly with your provider for best safety but be aware medicines can have different impact when taken at altitude and when under stress.

When planning your high altitude adventure remember to stay in touch with your body and your fellow trekkers! It is tempting to continue exercise assuming that you are simply tired, dehydrated, have low blood sugar, or low core temperature. Do not make the mistake of treating altitude sickness by drinking water, eating, or putting on more clothing. The mountain adventurer who misunderstands or mistreats altitude sickness and continues to climb could be risking serious or life-threatening consequences. Be safe, be prepared, and when in doubt, do not climb higher!

Remember the Golden rules. They will save your own or someone else’s life

1.     If you feel sick at altitude, assume it is altitude illness until proven otherwise. Some forms of altitude sickness can kill

2.     If you are suffering from altitude illness symptoms do not ascend further Never climb higher even if convinced it is only “Mild Altitude Sickness”

3.     If symptoms continue to worsen after resting at a certain altitude, continue to descend immediately. Ignoring ongoing altitude sickness is stupid and potentially a death sentence. Live to see altitude another day.

Remember these additional guides as well

1.     Share warning signs with traveling partners and never travel alone

2.     Avoid overexertion early on as you are ascending.

3.     Whenever possible, ascend slowly. The best prevention against all severe high altitude illness is to first acclimatize by spending a few days at 6,500 to 10,000 feet while taking day hikes from that altitude. Then, climb higher slowly: no more than 1,000-1,600 feet (300-500 meters) daily after passing 10,000 feet (3,000 meters).

4.     Sleep low when possible This means: Get over high passes or summit climbs quickly and then descend

5.     Caution with use of alcohol or sedatives. Avoid if possible.

6.     Rethink your trip if ill with pulmonary infection

7.     Be more aware if you have prior altitude illness

8.     Consider discussion with a mountain specialist regarding preventative medication.

9. Enjoy the mountains safely. It isn't hard once you learn enough about altitude.

10. The single best treatment for all forms of high-altitude sickness: get down off the mountain.

Remember to be informed before going to elevation. There are a variety of altitude illnesses including acute mountain sickness, pulmonary edema, cerebral edema, retinal 

Enjoy the hills!--Marybeth Lambe MD FAAFP