Monthly Archives: May 2021

Altitude Science, Exposure, Health, High Altitude, Mountaineering

Nail Abnormalities at High Altitude

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With summer just around the corner, more people will be hitting the mountains for some high altitude hikes and 14ers. There have been numerous anecdotal findings of mountaineers with changes to their fingernails after ascending the world’s tallest peaks, with the most common abnormalities being Mees’ lines, Muehrcke’s lines, and Beau’s lines. While the peaks in Colorado do not compare to those of the Himalayas, there is always a chance, albeit very low, that you may notice some changes to your nails after a high altitude expedition.

Both Mees’ lines and Muehrcke’s lines are types of leukonychia, which means “white nails”. Mees’ lines present as a single horizontal white band, sometimes multiple, located in the nail plate and are non-blanching. Throughout history, Mees’ lines have been associated with drug toxicity, such as from arsenic or thallium.4 Additionally, there are many systemic diseases that have been associated with Mees’ lines in which the body is experiencing high amounts of stress, such as with myocardial infarction, sickle cell crisis, and tuberculosis.4

Mee’s lines

One case report, “Mees’ lines in high altitude mountaineering”,  by Avinash Aujayeb details how a 27-year old man developed Mees’ lines after he traversed high altitudes in the Pakistani Karakorum range, attempting to scale a summit of 7031 meters.1 He acclimated to altitude at a camp located at 4000 meters,  and stayed for a total of 21 days. No medications were used for acclimatization. In his attempt to reach the summit, he became extremely fatigued and hypothermic, and turned around at 6900 meters. Upon return to sea level, he lost about 17 pounds of weight. Six weeks after his expedition, he developed non-blanching horizontal white lines on his nails, consistent with Mees’ lines. The lines eventually moved distally and completely disappeared. While the paper does not go on to hypothesize the cause of this man’s development of Mees’ lines, it seems reasonable that they appeared due to the stress the man endured as evidenced by his need to turn around early from fatigue and hypothermia, and likely hypoxia given the extreme altitude.

Muehrcke’s lines present as a pair of horizontal white bands located in the nailbed, the skin beneath the nail plate, making them blanchable (unlike Mee’s lines which are located within the nail itself). Muehrcke’s lines usually present on the 2nd, 3rd and 4th fingers, and typically spare the thumb. Historically, these lines are most associated with hypoalbuminemia as seen in a protein-losing condition of the kidney called nephrotic syndrome.4 They have also been found in disease states of systemic immunosuppression, such as in HIV, where the metabolism of the body is stressed and has decreased ability to make proteins. 4

Muehrcke’s lines

The discovery of Muehrcke’s lines was first published in the British Medical Journal in 1956 by Robert C. Muehrcke.4  In the paper, he details a study in which he compared 750 adult patients and healthy volunteers who had normal serum albumin against 65 patients known to have chronic hypoalbuminemia.  He saw that the pair of white horizontal lines were only in those with the chronic hypoalbuminemia, most specifically those with a serum albumin below 2.2 g/dL.4 Once these patients were treated and their albumin concentrations increased, the lines disappeared after a few weeks. He thought the findings suggested that Muehrcke’s lines were from an albumin deficiency due to poor nutrition.

In a letter to the editor of High Altitude Medicine and Biology, authors Windsor, Hart, and Rodway describe the presence of Muehrcke’s lines on Mount Everest after a 38 year old with no significant medical history noticed their appearance a few weeks after he had returned to sea level.3 There were two parallel horizontal lines under the nails of his 2nd, 3rd, 4th, and 5th digits, sparing the overlying nail. They believe the development of these nail findings were indeed from hypoalbuminemia , however do not believe it was from a nutritional deficiency as Muehrcke first described, because the climber had been healthy throughout his expedition and he maintained good nutrition.3 They attribute the findings to peripheral edema, which is a common finding in high altitude mountaineers. With this edema, fluid levels in the tissues increase. The authors believe this may have inhibited the growth of the nailbed, which then resumed with return to sea level.

Another nail finding from high altitude mountaineering is called Beau’s lines, which are an indented groove across the span of the nail horizontally, beginning at the base of the lunula. The lines result when nail formation is temporarily halted during episodes of stress, and usually present several weeks after the stressful incident.2 They are generally caused by local trauma to the nail, extreme temperatures, and toxicity from chemotherapy.4

Beau’s lines

There was a prospective study completed by authors Bellis and Nickol in High Altitude Medicine and Biology where the study participants were completing a research expedition in eastern Nepal in April and May of 2003.2 The maximum altitude reached varied from 5,142 to 6,476 meters and the length of stay of each individual also varied. The study found Beau’s lines developed in 1 out of 56 participants at 4 weeks, however by 8 weeks, 17 out of the 52 (or 33%) developed Beau’s lines. The authors hypothesized that the changes were possibly due to the hypoxic as well as hypobaric environment which could diminish the activity of the nail matrix. However, they did acknowledge the fact that there were other factors that could have resulted in the Beau’s lines, such as extreme cold conditions and possible injuries to the fingers due to the nature of the work of the researchers. No participants reported frostbite or any damage to the hand, however at night temperatures dropped as low as negative 20 degrees Celsius.

Clubbed fingers

These nail abnormaltities are less likely to be found during expeditions within the United States unless hiking in Alaska, which has Denali, the tallest peak in the US at 20,310 meters. Outside of Alaska, the tallest peak is Mount Whitney in California, which pales in comparison at 14,505 meters. Most of the case reports completed on these nail findings were from several week-long expeditions in the Himalayas. However, condition you may already be aware of is clubbing of the fingers. This presents as a bulbous enlargement of the fingertips caused by chronic hypoxia. During my five-week visit here, I have anecdotally heard from two different Summit County residents that they have many healthy and young friends with clubbed fingers. Unfortunately, I was unable to find any research on the prevalence of clubbed fingers among individuals living at high elevations, but I believe it is something that deserves to be looked into deeper. 

References

  1. Aujayeb, A. (2019). Mees’ lines in high altitude mountaineering. BMJ Case Reports, 12(3), 1. doi:10.1136/bcr-2019-229644
  • Bellis, F., & Nickol, A. (2005). Everest Nails: A prospective study on the incidence OF Beau’s lines after time spent at high altitude. High Altitude Medicine & Biology, 6(2), 178-180. doi:10.1089/ham.2005.6.178
  • Windsor, J. S., Hart, N., & Rodway, G. W. (2009). Muehrcke’s lines on Mt. Everest. High Altitude Medicine & Biology,10(1), 87-88. doi:10.1089/ham.2008.1079
  • Zaiac, M. N., & Walker, A. (2013). Nail abnormalities associated with systemic pathologies. Clinics in Dermatology,31(5), 627-649. doi:10.1016/j.clindermatol.2013.06.018

Makenna Schmidgall is a second-year physician assistant student at the Midwestern University Physician Assistant Program in Glendale, Arizona. She grew up in Gilbert, AZ, but left her desert home to attend New York University in the Big Apple where she earned a bachelor’s degree in Global Public Health/Biology. During her junior year of college, she began working as an ER scribe in multiple emergency departments of the Mount Sinai Health System in New York, NY. She enjoys gardening, hiking and playing with her new Labrador retriever puppy “Piper”.  

Acclimation, Altitude Science, COVID-19, Health, High Altitude, Pandemic, Technology

HAST: the High Altitude Simulation Test

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Maybe you are planning to ski or hike a 14er. Taking a leap of faith and moving out of the city and into the mountains. Or maybe it’s just taking a flight in a pressurized airplane cabin. Maybe you just spent 10 days in the hospital with rib fractures and are now anxious to return home to 9000 feet in elevation. You could be an individual that is worried you will miss out on that incredible work retreat to a beautiful mountain sanctuary due to your apprehension about your Chronic Obstructive Pulmonary Disease COPD.

Wouldn’t it be nice to know how you would respond to altitude prior to reaching your destination, so you could be better prepared?   

There is such a test. It is called HAST: High Altitude Simulation Testing. This test can simulate 8000 feet in elevation, in the safety of a doctor’s office at lower elevations.  HAST is a diagnostic test that can effectively calculate an individual’s supplemental oxygen needs prior to traveling to high altitude. The California Thoracic Society recommends that individuals diagnosed with severe airway disease, cystic fibrosis, neuromuscular disease, kyphoscoliosis, individuals who have been hospitalized for acute respiratory illness within the last 6 weeks, individuals with previous air travel intolerance, COPD, or cerebral vascular disease would benefit from a HAST prior to traveling to altitude (Corby-DeMaagd, 2020).

This test is performed by obtaining a patient’s blood pressure, heart rate/rhythm, and oxygen saturation at baseline. Once baseline vitals are complete the patient is monitored while breathing in a mixture of gases containing approximately 15.1% oxygen, simulating the FiO2 at an elevation of 8,000 feet. A patient;s oxygen saturation levels can be recorded by an arterial line (large IV in the wrist) monitoring the patient’s arterial blood gasses, or by an oxygen monitor attached to the patient’s finger or on a nasal cannula. This allows the physician to screen for hypoxia, arrhythmias, or other significant symptoms. If the patient becomes symptomatic, the oxygen levels are reassessed while providing the patient with supplemental oxygen to identify exactly how much oxygen would be needed to keep the patient comfortable at a higher altitude.  This test on average takes 2 hours to complete (Corby-DeMaagd, 2020).  

According to Mark Fleming, the supervisor of the Pulmonary Physiology Services at National Jewish Health in Denver, Colorado, for an individual to receive a HAST they would need a referral from a provider.  National Jewish Health is one of the few facilities in the nation that provides this service. Most patients that request this test in the state of Colorado are pilots that have had a recent ailment and need a work clearance prior to being exposed to the airplane cabin pressure, those that are interested in relocating to the mountains, planning on a high-altitude vacation and currently on supplemental oxygen, or those with a history of pulmonary embolism or lung resections.  Fleming states that they are anticipating an increase in High Altitude Simulation Testing being needed for patients that have recovered from COVID-19.  

However, there may be a vulnerable population that is not receiving the benefit of this test. Newborn babies that are delivered at 5000 feet but must return home to 8500 feet. Those that have experienced a chest trauma and must return home to altitude. Or maybe even those that have experienced an invasive surgery that involved the lungs, chest, spine, or abdomen.  These are all individuals that would benefit from knowing if they would need oxygen once they return back to elevation. Hopefully as people continue to heal from COVID the word will spread that this test is available to the public for those that are concerned about journeying to altitude.

Amanda Bergin is currently in her second year of her Family Nurse Practitioner Program for the Rural and Underserved at Regis University. She is a member of the class of 2021 and will be graduating in August. She started her medical career as a corpsman in the United States Navy and after the completion of her service, she returned to school to complete her bachelor’s degree of Science in Nursing at the Denver School of Nursing.  Amanda currently lives in a rural mountain community with very limited healthcare, and dreams to help her community start a family practice clinic. In her free time, she loves spending time with her family, fishing, camping and raising dairy goats.

Acclimation, Alcohol at Altitude, Altitude Science, Athletic Training, Health, High Altitude, High Altitude Training & Fitness

Effects and management of altitude on pre-existing cardiac conditions

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As someone with family history of cardiac illness and a personal history of both supraventricular tachycardia (SVT) and high blood pressure, I have always tried to manage my modifiable risk factors through a healthy diet and exercise. Over the past year or two, most of my exercise has been in the form of running, since it is more conducive to the schedule of a physician assistant student during COVID restrictions. However, in the past I have been a regular rock climber and soccer player. Through my own personal experience I have noticed that when I stick to a healthy diet, not giving in to my sweet tooth, and keeping up with regular exercise that my episodes of SVT are less frequent. However, recently I traveled up from Denver, Colorado for a rotation at the Ebert Family Clinic in the mountain town of Frisco, and in the first two days at high elevation experienced an episode of SVT for the first time in nearly 6 months.

In my first day at over 9000 feet, I experienced a slight headache after a full day seeing patients, but did not think much of it or even consider it to be a side effect of the altitude. I spent my first day at altitude without exercising but I decided that on day two I had acclimated enough to go for a short run. Midway into my run, and shorter of breath than I expected, I experienced an episode of SVT that lasted for about 2-3 minutes and forced me to sit for several more minutes to catch my breath. Catching my breath afterward took slightly longer compared to my normal episodes, which made sense to me given the reduced availability of oxygen, but it did lead me to wonder if the altitude was a contributing factor to precipitating an episode of SVT after several months without one.

About one year ago, High Altitude Health interviewed Dr. Peter Lemis, a cardiologist in Summit County, Colorado about his thoughts and findings practicing cardiology at elevation. The discussion included questions about arrhythmias at altitude and Dr. Lemis stated that “studies have shown that cardiac arrhythmias are increased initially, but people become acclimated after about 3-5 days and the risk returns to baseline”. However, Dr. Lemis also states that the studies may not have been conducted for a sufficient length of time due to his personal experience of seeing a great deal of both atrial fibrillation and atrial flutter in his own practice. He states that the hypoxia leads to an increase in arrhythmias, but that for atrial arrhythmias, patients may experience relief from them when placed on nocturnal oxygen. Dr. Lemis also notes that “many people have central apnea during sleep at altitude due to the brain’s blunted response to high CO2 and low O2”, which can be a risk factor for the development of heart problems. The use of Diamox can be helpful in acclimating to altitude due to making “your blood a little acidotic which increases your respiratory drive” and the use of nocturnal oxygen can also help with acclimatization to altitude.

In March of 2021, the journal of Frontiers in Medicine published an article titled Nocturnal Heart Rate and Cardiac Repolarization in Lowlanders with Chronic Obstructive Pulmonary Disease at High Altitude: Data from a Randomized, Placebo-Controlled Trial of Nocturnal Oxygen Therapy by Maya Bisang, Tsogyal Latshang, Sayaka Aeschbacher, et al. This study compared COPD patients at altitude with and without oxygen therapy at night and COPD patients not at altitude without oxygen looking at QT interval, heart rate, and SpO2. The results of the study found that without oxygen use at altitude patients experienced an increase in heart rate, a lengthened QT interval, and naturally, a lower SpO2 at night compared to those at altitude who utilized oxygen and those that were not at elevation. This study was observing patients that had COPD. The results could potentially be relevant to younger patients without COPD, like myself, but would need further research.

I also looked into information regarding high blood pressure at altitude and found some helpful information from the Institute for Altitude Medicine. They state that for patients visiting altitude with a history of hypertension (HTN), even if it is well controlled on pharmacotherapy, may still experience a temporary increase in blood pressure at altitude. “One explanation for this is due to the higher levels of adrenaline or stress hormones in your body due to lower oxygen levels,” as they describe. Their research has also found that increases in blood pressure at altitude generally return to base line after 1-2 weeks. In order to help manage HTN at altitude they recommend ensuring that blood pressure is well controlled at sea level, reducing salt from the diet, remaining on any medications for HTN, checking blood pressure at altitude, and observing for symptoms of HTN that would need medical care such as headache, dizziness, chest pain, or shortness of breath.

Through my research regarding effects of altitude and the possible role of them in my recent episode of SVT, I have found that altitude can have several different impacts on cardiac function that definitely could have played a role in triggering an episode. Coming to altitude, I likely had an increase in blood pressure to compensate for the reduced availability of oxygen that increased strain on my cardiac muscle. I may have had EKG changes overnight related to decreased responsiveness of my central nervous system to CO2 levels. I also had an increased risk of arrhythmia based on coming to elevation. It is possible that any or all of these effects could have contributed or triggered my episode of SVT. Thankfully, after almost a month of staying at altitude I have adjusted more and have not experienced another episode. I have continued to exercise after a short break to allow more time to acclimate, but I have not pushed myself as hard.

I have learned that no matter how healthy you are or what your risk factors are, there are important steps to stay healthy when coming to altitude. If possible, at least one day at an intermediate altitude can help your body begin to adjust to the change. Drinking plenty of water to stay hydrated and avoiding alcohol can lead to a more comfortable stay and more rapid acclimatization. Meeting with a healthcare provider could also allow you to start a prophylactic course of Diamox or supplemental oxygen use. Utilizing a personal pulse oximeter allows you to monitor your SpO2 level and determine if nocturnal supplemental oxygen could be useful as well. If you have risks for cardiac conditions or already have a diagnosis of heart disease, these recommendations are even more important to prevent poor outcomes including myocardial infarctions due to reduced oxygen availability. Finally, it is important to remember that traveling to altitude is not a benign choice and a discussion with your healthcare provider is important to be sure that your personal risks are appropriately managed so that you can enjoy your trip to high elevation.

Justin Frazier is currently in his second year of PA school at Red Rocks Community College in Arvada, CO, a member of the class of 2021 graduating in November. He attended Appalachian State University in Boone, NC for his undergraduate degree majoring in Cell and Molecular Biology with a double minor in Chemistry and Medical Humanities. During his undergraduate he worked for two and a half years as a CNA at a local nursing and rehabilitation facility. After completing his undergraduate degree he started working as an EMT for almost a year before transitioning to work in a family medicine office where he worked as a Medical Assistant until starting PA school. He enjoys working in a primary care setting where he can help to keep people healthy throughout their lives and wants to pursue a career in pediatrics after graduating this year. He enjoys hiking, camping, rock climbing, and spending time with his wife and young son.