Often, at high altitude we hear complaints of gas pain and increased flatus in our infant population. Parents often wonder, are we doing something wrong? Is my child reacting to breastmilk, or showing an intolerance to certain foods? Actually there is another explanation for increased flatus and gas pain in the high-altitude region of Colorado.
The term HAFE was coined by Dr. Paul Auerbach and Dr. York Miller and published in the Western Journal of Medicine in 1981. Their discovery began In the summer of 1980, when the two doctors were hiking in the San Juan Mountains of Colorado on a quest to summit three 14ers. During their ascent they noticed that something didn’t smell right! As the pair continued to emit noxious fumes, they began to put their scientific brains to work and discovered HAFE. The symptoms include an increase in frequency and volume of flatus, or in other terms an increase in toots! We all have familiarity in watching our bag of potato chips blow up when reaching altitude or our water bottle expanding as we head into the mountains. This reaction is due to a decrease in barometric pressure. Based on Boyle’s law, decreased barometric pressure causes the intestinal gas volume to expand, thus causing HAFE (Skinner & Rawal, 2019).
To my surprise, a gas bubble the size of a walnut in Denver, Colorado (5280 ft) would be the size of a grapefruit in the mountain region of Summit County, CO (8000+ ft)! Trapped gas is known to lead to discomfort and pain. The use of simethicone may have merit in mitigating the effects of HAFE. Simethicone works by changing the surface tension of gas bubbles, allowing easier elimination of gas. This medication, while benign, can be found over the counter and does not appear to be absorbed by the GI tract (Ingold, C. J., & Akhondi, H., 2022).
While this phenomenon may not be as debilitating as high-altitude pulmonary edema (HAPE), it deserves recognition, as it can cause a significant inconvenience and discomfort to those it inflicts. As the Radiolab podcast explained in their episode The Flight Before Christmas , expelled gas in a plane or car when driving up to the mountains can be embarrassing. While HAFE can be inconvenient, it is a benign condition and a matter of pressure changes rather than a disease or pathological process. We would love to talk more about HAFE at Ebert Family Clinic if you have any questions or concerns!
A bald eagle flies toward its nest atop a bare lodgepole pine.
As always, stay happy, safe, and healthy 😊
Taylor Hollingsworth is finishing her final semester as a family nurse practitioner (FNP) student at Georgetown University. Originally from the east coast, Taylor plans to start her FNP career in North Carolina close to family. She has a passion for pediatric and family wellness and has worked as a pediatric intensive care unit nurse for 6 years! In her free time, Taylor loves to hike, fly fish, run, and spend time with her fiancé Logan.
References
Auerbach, P. & Miller, Y. (1981). High altitude flatus expulsion. The Western Journal of Medicine, 134(2), 173-174.
Health care providers and people who live at altitude often believe that living in the mountains protects from altitude related illness. And yes, there are many ways the body acclimatizes over days, weeks, months, and years, as addressed in previous blog entries. However, as a physician who has practiced in high altitude communities for over 20 years, my personal observation that we are still at risk for serious complications was reenforced by a recent publication by Dr. Santiago Ucrós at the Universidad de los Andes School of Medicine in Santa Fe de Bogotá, Colombia. His article, High altitude pulmonary edema in children: a systemic review, was published in the journal Pediatric Pulmonology in August 2022. He included 35 studies reporting 210 cases, ages 0-18 years, from 12 countries.
Consistent with our experience in Colorado, the most common ages were 6-10 years and second most common 11-15 years. I have not seen or read any reports of adults affected. Cases included two deaths, which I have also seen here.
I receive reports on any of my patients seen in urgent or emergency care. Accidents, avalanches, and suicide attempts are what we think of first needing emergency care in the mountains. However, the most common critical condition is Reentry HAPE. This is a form of pulmonary edema that can occur in children who are returning from a trip to lower altitude. Think visiting Grandma during school break. Dr. Ucrós’ review also confirms that all presentations of HAPE (classic, as in visitors, reentry, and HARPE, resident children with no history of recent travel) are more common in males by a 2.6 to 1 ratio. Analysis of time spent at lower altitude before the episode showed a range of 1.6 to 30 days with a mean of 11.3 days. Mean time between arrival and onset of symptoms for all types of HAPE was 16.7 hours. The minimum altitude change reported in a HAPE case was 520 meters (1700 feet), which is the difference between Frisco, CO (Summit County) and Kremmling, CO (Grand County, the next county over). A new form of HAPE in high altitude residents who travel to higher altitude was designated HL-HAPE in this review. A case report will be featured in an upcoming blog interview with a Summit County resident who traveled to Mt. Kilimanjaro.
As with all cases of HAPE, the victims develop a cough, sound congested as the fluid builds up in their lungs, have fatigue, exercise intolerance, with rapid onset over hours of exposure to altitude, usually above 8000 ft or 2500m. Oxygen saturations in this paper ranged from 55 to 79%. My patients have been as low at 39% in the emergency room. Children presenting earlier or with milder cases come to the office with oxygen saturations in the 80’s. An underlying infection such as a cold or influenza is nearly always present and considered a contributing factor. Everyone living or visiting altitude should have an inexpensive pulse oximeter which can measure oxygen on a finger. Access to oxygen and immediate treatment for values under 89 can be life-saving.
The recurrence rate for all types of HAPE is about 20%. Most children never have another episode, but some have multiple. Preventive measures include slower return to altitude, such as a night in Denver, acetazolamide prescription taken two days before and two days after, and using oxygen for 24-48 hours on arrival. Most families learn to anticipate, prevent, or treat early and don’t need to see a health care provider after the first episode.
On January 26, 2023 I met with Dr. Ucrós and other high altitude scientists including Dr. Christina Eichstaedt, genetics expert at the University of Heidelberg in Germany, Dr. Deborah Liptzen, pediatric pulmonologist, and Dr. Dunbar Ivy, pediatric cardiologist, both from the University of Colorado and Children’s Hospital of Colorado, and Jose Antonio Castro-Rodríguez MD, PhD from the Pontifica Universidad Católica in Santiago de Chile.
We discussed possible genetic susceptibility to HAPE and hypoxia in newborns at altitude with plans to conduct studies in Bogotá and Summit County, Colorado.
Epigenetics slide from speaker at Hypoxia conference in La Paz Bolivia, 2022
The CDC defines epigenetics as “the study of how your behaviors and environment can cause changes that affect the way your genes work… epigenetic changes are reversible and do not change your DNA sequence, but they can change how your body reads a sequence.”1 Examples of epigenetic changes include methylation, histone modifications, and non-coding RNAs. Researchers have postulated the involvement of epigenetics in an organism’s adaptations to hypoxic high-altitude environments. After looking into this topic, I questioned if epigenetics may be the bridge to the permanent physiologic alterations in organisms living at high altitudes.
Hypoxia Inducible Factor-1 (HIF-1) is a nuclear transcription factor activated in hypoxia states, and regulates several oxygen-related genes. The role of epigenetics, specifically methylation of HIF-1 in the expression of the erythropoietin gene, in states of hypoxia was researched. Erythropoietin was chosen due to it being a widely known protein that stimulates erythropoiesis in states of hypoxia. It was confirmed that HIF-1 binds to a HIF-1 binding site (HBS) on the erythropoietin enhancer and will induce transcription of erythropoietin.2 CpG methylation in the HBS interferes with HIF-1 binding, thus inhibiting the activation of transcription of erythropoietin.2 They also found that there were several other oxygen-related genes that were susceptible to similar epigenetic changes.2 Another study investigating HIF-1 and its binding to HIF-1 response element (HRE) upstream to a target gene confirmed the potential for epigenetic changes, specifically methylation. They found that this HIF-1 binding site has a CpG dinucleotide, making it inherently susceptible to methylation.3 To clarify, the most notable epigenetic change is the methylation of cytosine located 5’ to guanine, known as CpG dinucleotides.3 Again, they reported that methylation of the CpG island in the HIF-1 binding site upstream of the target gene, erythropoietin, was negatively correlated with its expression.3
Furthermore, research on epigenetic changes in rats exposed to long and short-term intermittent hypoxic environments and their room air recovery treatments suggests there is a long-term effect in rats exposed to long-term intermittent hypoxia.4 Rats were exposed to short-term (10 days) and long-term (30 days) intermittent hypoxia resembling obstructive sleep apnea oxygen profiles.4 The short-term hypoxic rats treated for 10 days at room air reversed their altered carotid body reflexes including hypertension, irregular breathing, and increased sympathetic tone. While the long-term hypoxia rats treated for 30 days at room air did not have a reversal of altered carotid body reflexes.4 There were similar results in reactive oxygen species (ROS) and antioxidant enzyme (AOE) levels. The long-term hypoxia rats had increased levels of ROS and decreased AOEs in their recovery periods compared to the short-term hypoxia rats.4
Erythropoietin is not the only oxygen-related gene that is affected. For example, a study looked at the methylation profiles of Tibetan and Yorkshire pigs under high-altitude hypoxia. IGF1R and AKT3 were two notable differentially methylated genes found to have high expression and low methylation levels in Tibetan pigs that suggest a role in adaptation to hypoxic environments.5 Both genes are responsible for cell proliferation and survival.5 Tibetan pigs are known to have become physiologically adapted to their high-altitude hypoxic environment over generations and epigenetic changes were verified in the genome-wide sequence ran in this study.5 This study alludes that epigenetics is not only a bridge but may be a part of the permanent physiologically selected adaptations to ensure survival at high altitudes.
In conclusion, research demonstrates a variety of epigenetic changes that are taking place in these high-altitude hypoxic environments. The research suggests that they may likely be tissue-specific as well. There are definite knowledge gaps in the exact roles that epigenetics may play in hypoxic environments and gene expression. There is room for more research and identifying alterations to epigenetics to improve human physiologic adaptations to hypoxia.
2. Wenger, R.H., Kvietikova, I., Rolfs, A., Camenisch, G. and Gassmann, M. (1998), Oxygen-regulated erythropoietin gene expression is dependent on a CpG methylation-free hypoxia-inducible factor-1 DNA-binding site. European Journal of Biochemistry, 253: 771-777. https://doi.org/10.1046/j.1432-1327.1998.2530771.x
3. Yin H, Blanchard KL. DNA methylation represses the expression of the human erythropoietin gene by two different mechanisms [published correction appears in Blood 2000 Feb 15;95(4):1137]. Blood. 2000;95(1):111-119.
4. Nanduri J, Semenza GL, Prabhakar NR. Epigenetic changes by DNA methylation in chronic and intermittent hypoxia. Am J Physiol Lung Cell Mol Physiol. 2017;313(6):L1096-L1100. doi:10.1152/ajplung.00325.2017
5. Zhang B, Ban D, Gou X, et al. Genome-wide DNA methylation profiles in Tibetan and Yorkshire pigs under high-altitude hypoxia. J Anim Sci Biotechnol. 2019;10:25. Published 2019 Feb 5. doi:10.1186/s40104-019-0316-y
Emily Paz is a third-year medical student at Rocky Vista University College of Osteopathic Medicine and is looking forward to pursuing a career in orthopedics. She is from the central coast of California and earned her Bachelor of Science degree in General Biology from the University of California San Diego. She worked in an emergency department as an EMT after her undergraduate education which reaffirmed her passion and curiosity for medicine. In her free time, she enjoys snowboarding, practicing Muay Thai, cooking, and spending time with family and friends.
Does altitude increase or decrease risk of strokes? As one review put it, “Due to limited literature, lack of large series, and controlled studies, the understanding of stroke at high altitude is still sketchy and incomplete”. What is clear is that stroke at high altitude can often be misdiagnosed (or underdiagnosed), due to the similarity of initial presentation with high altitude cerebral edema (HACE). Both conditions present with imbalance or ataxia, and both can present with focal neurological deficits. There are few large urban populations at high altitude (Addis Ababa in Ethiopia is 7,726 ft), so medical providers have fewer resources. Without the ability to perform neuroimaging with a CT scan or MRI in a timely manner a diagnosis of HACE vs. stroke could be uncertain. HACE often causes global cerebral dysfunction, differentiating it from an early stroke before the onset of focal symptoms can and often does prove challenging.
While the prevalence of strictly hemorrhagic and ischemic strokes at high altitude remains murky, it is known that exposure to high altitude can result in conditions such as TIA, cerebral venous thrombosis (CVT), seizures, and cranial nerve palsies. Most of the research that has been done on strokes is focused on “moderate” and “high” altitudes, as opposed to “very high” or “extremely high” altitudes. As such, there is very little research on populations living at 3500m or higher. There was at least one tangible piece of evidence indicating that the higher the elevation, the earlier the mean onset of stroke – Dhiman et al. (2018) found that at an elevation of 2,000m, the mean age of onset of stroke was 62 years. The age decreased to a mean of 57.9 years at 2,200m in another study (Mahajan et al. (2004)). Yet another study (Razdan et al. (1989)) found 10.9% of the patients in their sample suffered strokes aged < 40, though this was at an altitude of only 1,530m. Some reports suggest higher stroke prevalence at higher altitudes, and at a strikingly young age – between age 20 and age 45.
Student presentation on stroke at altitude at Colorado Medical Society meeting 2022
There have been mixed results on the effect that altitude has on strokes. One systematic review study found 10 studies displaying an increase in stroke prevalence with higher altitude, 5 other studies showing that altitude was actually protective against stroke, and 2 studies in which the results were ambiguous. This study and other sources alluded to the fact that poorer stroke outcomes at higher altitude may be due to polycythemia and increased viscosity of blood. Specifically, Ortiz-Prado et. al noted that “living in high-altitude regions (>2500m) increases the risk of developing thrombosis through hypoxia-driven polycythaemia which leads to a hypercoagulation unbalance”, which was associated with increased risk for stroke. Ortiz-Prado et. al noted that most of their info came from “very few cross-sectional analyses”. These analyses did find “a significant association between living in high-altitude regions and having a greater risk of developing stroke, especially among younger populations”. When the effects of altitude on stroke were broken down by race (Gerken, Huber, Barron, & Zapata, 2022) it was found to be protective in some populations (Whites, African Americans), but detrimental in other populations (Hispanics, Asian-Pacific, and American-Indian). Going back to the work of Ortiz-Prado et. al, altitude increased the risk of stroke at elevations above 3500m, when the time spent at this elevation was at least 28 days, and more so in younger persons (below the age of 45). At lower elevations, between 1500m and 3500m, increased / easier acclimatization and adaptation to hypoxia seemed to offer protective effects against the risk of stroke. Chronic exposure to hypoxia at high altitude triggers adaptive / compensatory mechanisms, such as higher pulmonary arterial flow and improved oxygen diffusing capacity. Ortiz-Prado et. al concluded that a window of ideal elevation seems to exist – below an altitude of 2000m the adaptive mechanisms do not seem to be sufficient to yield a protective effect – however, above 3500m, adaptive mechanisms may actually become maladaptive (excessive polycythemia & blood stasis), yielding a higher risk for stroke. A lack of any adaptation (i.e. in altitude naïve persons) was even more detrimental at such high altitudes, with the authors concluding that “above 3500–4000m, the risk of developing stroke increases, especially if the exposure is acute among non-adapted populations” (Ortiz-Prado et. al, 2022).
Strokes are more common in males compared to females, and this held true at altitudes of 3380m, 4000m, and 4572m. In addition to the standard vascular risk factors such as hypertension, smoking, and diabetes, the higher incidence of polycythemia in persons living at high altitude is thought to play a role. One study (Jha et al. (2002)) found that 75% of the patients in their sample who had suffered strokes had some form of polycythemia – this was at an altitude of 4270m. (Dr. Christine Ebert-Santos of Ebert Family Clinic in Frisco, Colorado at 2743m suspects everyone who lives at altitude has polyerythrocythemia as more accurately described by Dr. Gustavo Zubieta-Calleja of La Paz, Bolivia at 3625m.)
Only about 2% of the world’s population resides at what is considered “high altitude”. Given the current world population (over 8 billion, 5 million), that is still over 160,100,000 people. The sheer number of people that may be at increased risk of stroke is all the more reason for us to act, and act soon, to get more research done. This is further exemplified by the fact that “cerebrovascular events or stroke is the second leading cause of death worldwide, affecting more than 16 million people each year” (Ortiz-Prado et. al). Guidelines need to be implemented to assist in the diagnosis and treatment of stroke at high altitude, to help differentiate it from related conditions such as HACE, giving patients the standard of care that they need and deserve. While a fascinating topic, stroke seems to be delegated to the sidelines in the mountains, cast aside by culprits such as HAPE, HACE, altitude sickness, and hypoxia. More research, more resources, and more funding need to be funneled into understanding stroke at higher altitudes. Overall, it is clear living at or even exposure to higher altitudes can result in a multitude of neurological symptoms, and that a higher incidence of stroke may yet be one of them.
Ortiz-Prado E, Cordovez SP, Vasconez E, Viscor G, Roderick P. Chronic high-altitude exposure and the epidemiology of ischaemic stroke: a systematic review. BMJ Open. 2022;12(4):e051777. Published 2022 Apr 29. doi:10.1136/bmjopen-2021-051777
Gerken, Jacob (MS), Huber, Nathan (MS), Barron, Ileana (MD, MPH-S), Zapata, Isain (PhD). “Influence of Elevation of Stroke and Cardiovascular Outcomes”. Poster presented at a conference in Colorado, in 2022.
Born in Salt Lake City, Utah, Piotr Poczwardowski has also lived in Upstate New York, Florida, and Colorado (where he spent the 13 years prior to moving to Glendale for PA school). While attending the University of Denver, he volunteered at a nearby hospital Emergency Department, and also participated in a study abroad program in Italy. After earning a degree in Psychology, he worked as both a Primary Care Medical Scribe and Neurology MA. His main hobbies include skiing, watching movies, hiking, swimming, playing video games, reading, and playing ping pong.Piotr has also volunteered at the Sky Ridge Medical Center Emergency Department and secured a job as a Primary Care Medical Scribe after graduating from the University of Denver in 2018. Piotr is now attending Midwestern University’s PA program in Glendale, AZ.
Louie was excited to get out on the slopes after spending Thanksgiving with family in Vermont. He got tired early and felt his breathing was harder than usual, leaving early to go home and rest. As a competitive skier he thought that was strange. But he was getting over a cold. He could not have imagined that in 24 hours he would be in the emergency room, fighting for his life.
Louie experienced a dangerous condition, set off by altitude, and inflammation from his “cold”, that caused his lungs to fill with fluid. His oxygen saturation was 54 % instead of the normal 92, he had been vomiting and feeling very weak and short of breath. His blood tests showed dehydration, hypoxemia and acute kidney injury. His chest x-ray looked like a snowstorm. He was transferred to Children’s Hospital in Denver and admitted to the intensive care unit.
The diagnosis of Re-entry HAPE was confirmed by echocardiogram showing increased pressures in his lungs. He improved rapidly with oxygen and low altitude.
Re-entry HAPE is not rare, affecting several Summit County children every year. Many do not come to medical attention because after their first episode parents carefully monitor their oxygen and have a concentrator available in their home when they return from travel.
Medical providers may not be aware of this risk, expecting that children living at altitude are acclimatized. (See previous blog entry on Acclimatization vs. Adaptation, April 17, 2019) Re-entry HAPE seems to occur mostly in children between the ages of 4 and 15. Inflammation, such as a viral respiratory infection, seems to play a role. Trauma may also predispose a returning resident to Re-entry HAPE, as described in our blog post from February 5, 2018, Re-entry HAPE in High Altitude Residents.
Louie agreed to share his story on our blog to help educate medical personnel and families living in the mountains about this dangerous condition. Further research will help define who is at risk. The University of Heidelberg recently published an article on the genetics of pulmonary hypertension (HARPE is the New HAPE) and is interested in testing families here who have had more than one person affected by HAPE.
You do not have to be a surfer to have surfer’s ear, but what is it exactly?
Not to be confused with swimmer’s ear surfer’s ear or exostosis of the ear auditory canal is when there is the presence of multiple benign boney outgrowths. It is quite common in individuals who have repeated exposure to cold water or wind, which typically ends up being those who surf waves in the pacific.
So now that we know what surfer’s ear is, how can we tell if we have it?
The diagnosis of Surfer’s ear is made by visual exam with an otoscope by a medical provider. Generally, there are no symptoms of Surfer’s ear unless there are multiple bony outgrowths, or the ones present are occluding your ear canal. In those cases, you may experience ear infections as these outgrowths can narrow the ear canal causing water and debris to become trapped and cause an infection. When there is significant occlusion of the ear canal typically 90% or more conductive hearing loss may occur.
What is the treatment for surfer’s ear?
A great preventative tool, to decrease the occurrence of these bony outgrowths is to wear ear protection like ear plugs when you have exposure to cold water or earmuffs when exposed to cold winds. As mentioned above, when there is only a few and/or small boney outgrowths there tends to be no associated symptoms and in those cases no need for treatment. In those, however, that continue to have exposure to cold water/winds, have several boney outgrowths and/or significant occlusion the only definitive treatment is to have those bony outgrowths removed surgically, this is typically done by an Ear, Nose, and Throat specialist.
References
Surfer’s ear. UCI Health Otolaryngology. https://www.ucihealth.org/medical-services/ear-nose-throat-ent/hearing-ear-disorders/surfers-ear. Accessed October 11, 2022.
Weber PC. Etiology of Hearing Loss in Adults. UpToDate. https://www.uptodate.com/contents/etiology-of-hearing-loss-in-adults?search=surfers+ear§ionRank=1&usage_type=default&anchor=H9&source=machineLearning&selectedTitle=1~150&display_rank=1#H9. Published March 15, 2022. Accessed October 11, 2022.
Gabriela Rodriguez Ortega is a second year Physician Assistant student at Red Rocks Community College in Arvada, CO. She grew up in South Florida and received a Bachelor of Science in Biomedical Sciences and Bachelor of Arts in Psychology from the University of South Florida (Go Bulls!). Prior to PA school, she held many positions in the medical field including ENT medical assistant/scribe, pharmacy technician and ER medical scribe. In her free time, she enjoys spending time with family and friends, running, hiking, roller skating and playing guitar.
The 8th Chronic Hypoxia Symposium is recently took place in La Paz, Boliva, and I had to pleasure of hearing Dr. Jorge Luis Velez’ presentation on altitude, obesity, and COVID-19 survival rates. Dr. Velez is an intensive care doctor and the head of critical medicine at Pablo Arturo Suarez Hospital in Quito, Ecuador, as well as being a professor at the Central University of Ecuador. With Quito being the second highest in elevation capital in the world at 9,350 feet, Dr. Velez understands the effects of altitude on the human body.
Dr. Velez conducted a study among 340 unvaccinated adult patients with severe COVID-19 infections requiring intubation. Of the 340 patients, 45% were obese, 43% were overweight, and 12% were of normal weight. The results of the study showed that obese patients had significantly reduced mortality rates and higher rates of successful extubation when compared to the overweight and normal weight groups. Successful extubation is commonly described as extubation without the need for re-intubation within 72 hours. Obese patients were found to have a 31.17% mortality rate and an 81.03% rate of successful extubation. Overweight patients were found to have a 40.14% mortality rate and a 73.00% rate of successful extubation. Patients of normal weight were found to have a 48.72% mortality rate and a 53.85% rate of successful extubation.
These results are surprising given that obesity is a widely accepted risk factor for high severity COVID-19 infections and increased mortality. Other factors that may have contributed to the increased survival rates of obese patients with severe COVID-19 infections is that in their study, the obese patients happened to be on average younger and a higher proportion of males. Despite variables in age and sex, Dr. Velez still concludes with statistical significance that “patients with obesity had a 52% less probability of dying in relation to those of normal weight.”
Despite this emerging research, we still recommend maintenance of a healthy weight and lifestyle, as the effects of a healthy weight have been extensively researched and proven to be beneficial for a heart health, joint health, mental health, sleep, the digestive system, and more.
Family Nurse Practitioner Ana Sofia Bedoya administering the new bivalent COVID-19 vaccine to Dr. Chris in her office at Ebert Family Clinic in Frisco, CO.
Looking for other ways to protect yourself from COVID-19?
The new bivalent vaccine uses the same technology with upgraded protection against the omicron variant. The vaccine is the best way to reduce risk for you and your family during the holiday season, as well as protecting from reinfection if you’ve already had COVID-19.
References
Luis Velez, J., 2022. Altitude Promotes Better Survival Rates in Critically Ill Obese Patients with COVID-19.
Artime, C. A. A., & Hagberg, C. A. H. (2014, June). Tracheal Extubation. Respiratory Care, 59(6), 991–1005. https://rc.rcjournal.com/content/respcare/59/6/991.full.pdf#:~:text=Successful%20extubation%20is%20dependent%20on%20two%20factors%3A%20the,a%20planned%20extubation8%3B%20however%2C%20this%20definition%20does%20not
Cameron Santiago is a second-year Physician Assistant Student at Red Rocks Community College in Arvada, CO. He grew up in Colorado Springs and received his undergraduate degree in Biology from Colorado State University. Prior to PA school, he was an inpatient phlebotomist and urgent care technician. In his free time, he enjoys fishing, hiking, and spending time with his dogs and family.
It took ten years for me to convince high altitude experts that children living in the mountains get high altitude pulmonary edema (HAPE) without leaving home. My observations were published in 2017 in the Journal of High Altitude Medicine and Biology,
High-Altitude Pulmonary Edema in Mountain Community Residents
This week Dr. Jose A Castro-Rodriguez MD PhD ATSF discussed HAPE in children at the 8th World Hypoxia conference in La Paz including the now renamed high altitude resident pulmonary edema (HARPE) in his presentation.
Dr. Castro-Rodriguez emphasized the importance of recognizing the three forms of HAPE, including reentry HAPE when children return to the mountains from vacation, since these can be life threatening.
My work has been cited in articles by pulmonologists Deborah Liptzin and Dunbar Ivy from Children’s Hospital of Colorado and geneticist Christine Eichstaedt and her team at the University of Heidelberg.
At Ebert Family Clinic we give every patient/family a free pulse oximeter. The ability to measure the oxygen saturation of anyone with cough, congestion, or fatigue can facilitate early treatment with oxygen and prevent visits to the emergency room, hospital and intensive care unit.
I recently received first prize for a poster presentation on HARPE at the fall Colorado Medical Society meeting, and second prize for a poster on Trauma and HAPE.
For more information about HAPE, HARPE and Trauma-related HAPE, see previous blog entries.
References
Ebert-Santos C. High-Altitude Pulmonary Edema in Mountain Community Residents. High Alt Med Biol. 2017 Sep;18(3):278-284. doi: 10.1089/ham.2016.0100. Epub 2017 Aug 28. PMID: 28846035.
Giesenhagen AM, Ivy DD, Brinton JT, Meier MR, Weinman JP, Liptzin DR. High Altitude Pulmonary Edema in Children: A Single Referral Center Evaluation. J Pediatr. 2019 Jul;210:106-111. doi: 10.1016/j.jpeds.2019.02.028. Epub 2019 Apr 17. PMID: 31005280; PMCID: PMC6592742.
Liptzin DR, Abman SH, Giesenhagen A, Ivy DD. An Approach to Children with Pulmonary Edema at High Altitude. High Alt Med Biol. 2018 Mar;19(1):91-98. doi: 10.1089/ham.2017.0096. Epub 2018 Feb 22. PMID: 29470103; PMCID: PMC5905943.
Eichstaedt CA, Mairbäurl H, Song J, Benjamin N, Fischer C, Dehnert C, Schommer K, Berger MM, Bärtsch P, Grünig E, Hinderhofer K. Genetic Predisposition to High-Altitude Pulmonary Edema. High Alt Med Biol. 2020 Mar;21(1):28-36. doi: 10.1089/ham.2019.0083. Epub 2020 Jan 23. PMID: 31976756.
HAPE can affect long term locals too. There is no specific test to diagnosis HAPE leading to delayed treatment or improper treatment, including death.
HAPE is defined as fluid accumulation in the lungs when an individual spends about 48 hours at elevations of 8,200 feet or higher. This can occur when 1) tourists who are not accumulated to high altitudes appropriately 2) locals who re-enter high altitude after being at lower elevation for a period of time or 3) long term residents who develop an illness.
What are the signs and symptoms you ask? Exhaustion, dyspnea on exertion, productive cough, tachypnea, tachycardia, low oxygen saturation levels, and crackles upon lung assessments are the most common to be seen. These are very generic symptoms and resemble many other diseases, such as pneumonia and asthma, leading to misdiagnosis and improper treatment.
How is HAPE treated?
The answer is simple, oxygen. The body is being deprived of oxygen and is unable to feed our cells. By giving oxygen (either through an artificial source or returning to lower elevation) and allowing the body to rest, the body is able to meet its demand for oxygen and symptoms resolve. If one receives oxygen and symptoms do not improve, there is most likely an underlying cause that is contributing to the symptoms unrelated to HAPE.
A pulse oximeter is the easiest way that one can monitor their oxygen levels at home. This device can be purchased over the counter, relatively inexpensive, and easy to use. By placing the pulse oximeter on one’s finger, the device will read the individual’s oxygen level which should be greater than 90% (when at altitude). The heart rate will also be recorded which tends to be between 60-100 beats per minute when at rest for adults.
References
A new mechanism to prevent pulmonary edema in severe infections. Lung Disease News. (n.d.). Retrieved September 2, 2022, from https://lungdiseasenews.com/2015/01/14/researchers-discover-a-new-mechanism-to-prevent-pulmonary-edema-in-severe-infections/
Bhattarai, A., Acharya, S., Yadav, J. K., & Wilkes, M. (2019). Delayed-onset high altitude pulmonary edema: A case report. Wilderness & Environmental Medicine, 30(1), 90–92. https://doi.org/10.1016/j.wem.2018.11.002
Fixler, K. (2017, October 12). Colorado doctor: Health effects of living in mountains unknown to medical establishment. SummitDaily.com. Retrieved September 2, 2022, from https://www.summitdaily.com/news/summit-county-doctor-makes-a-case-for-high-altitude-disorder-that-affects-even-the-acclimated/
I had the honor of interviewing Andrew Breithaupt who recently retired from US Customs and Border Protection in the Department of Homeland Security where he served as an Air Interdiction Agent piloting multiple types of aircraft. He currently serves as a Lieutenant Colonel on active duty for the US Army, stationed in Minneapolis, MN. He began Army flight school in 1992 to become a helicopter pilot, ultimately qualifying in 4 different types of Army helicopters including the UH-1H, OH-58, AH-1, and the AH-64 Apache for which he became an Instructor Pilot training new Army aviators at Fort Rucker, Alabama. Later he began his transition to fixed-wing aircraft in the civilian community. After nearly 10 years of Army active duty and multiple overseas tours, he was selected to enter service for US Customs and Border Protection where he served as a federal law enforcement agent for over 20 years, retired in December of 2021. He holds his commercial pilot license for single engine & multi-engine fixed wing as well as rotorcraft with instrument privileges and aircraft type ratings. He has over 30 years of aviation experience and more than 2,500 hours of flight time over his career. I sat down to chat with him about his accomplished career and learn more about his aviation and altitude expertise.
In army flight school, specifically aeromedical training, he was taught the effects of aviation on the body. One of the first lessons they learned in their training was how to recognize the early warning signs of hypoxia. These include shortness of breath, dysphoria, nausea, vomiting and lightheadedness. This type of training is often done in altitude chambers, so trainees can experience these effects before they are in the air, including how aviation can affect your vestibular senses. A position change as simple as looking down to change a radio or instrument can completely disorient a pilot due to the change in direction of the fluid within the inner ear against the cilia. This can lead to the sensation that the plane has rotated and flying sideways. They are taught to trust their instruments because an overcorrection can lead to what they teach in flight school as a “death spiral.” The training is often done in a Barany Chair and simulates vestibular senses experienced during flight.
Elevation in Summit County, Colorado ranges from 7,947 feet to 14,270 feet, the highest peak being Gray’s Peak. With people living as high as 11,200 feet, as Andrew does at his home in Blue River located south of of Breckenridge, CO. Andrew shared some very interesting aviation altitude requirements which might surprise some. He spent much of his career operating non-pressurized helicopters and Federal Aviation Regulations prohibited him from going between 10,000 feet to 12,000 feet for more than 30 minutes without oxygen. When flying above 12,000 feet, pilots are required to have supplemental oxygen regardless of the amount of time spent at that elevation depending on the category of aviation being conducted such as commercial operations. This is according to the CFR (Code of Federal Regulations) Part 135 which governs commercial aircraft operations. How interesting is it that pilots have these regulations, yet many people who live in Summit County or those summiting 14ers (peaks at 14,000 ft. or above) are at or above these elevations with no supplemental oxygen on a daily basis. When flying private aircraft, CFR part 91.211 specifies flight crew can fly without pressurization or supplemental O2 below 14,000 feet and passengers below 15,000 feet.
While in the Army, Andrew would rarely operate aircraft above 8,000 feet and would typically not have supplemental oxygen on board. They were trained to begin descent immediately if they were to notice the early signs of hypoxia. Keeping a pilot’s license requires strict annual or even semi-annual FAA physicals and continued training to ensure their bodies can withstand the effects of aviation. As you can imagine those holding these licenses are some of the most fit men and women in the country. Andrew rarely felt the effects of altitude even with altitude changes as great as 8,000 feet coming from sea level. He would typically remain at these elevations for two hours or less piloting non-pressurized aircraft.
To give some perspective, when you hop on a commercial flight for your next adventure these planes typically fly around 28,000 to 36,000 feet of elevation. When beginning the ascent, the aircraft pressure stabilizes at 6,000 to 8,000 feet, approximately when the dreaded “popping of the ears” is felt. Supplemental oxygen and quick donning masks are required on all these aircraft in case depressurization were to occur due to the rapid hypoxia which would occur at such high altitudes.
Andrew moved to Summit County in November of 2021 from Stafford, VA with his wife and five sons ages 24, 22, 19, 14, and 11. Andrew and his family spent a significant amount of time in Summit County for snowboarding and skiing competitions and quickly fell in love with the area prior to spending the last 5 years living in Stuttgart, Germany. This is when they decided one day, they would become full-time residents of the county. They moved here for the “people, climate and lifestyle,” a combination I am learning is hard to beat outside of Summit County. With ski and snowboard season right around the corner, he and his family are excited to get back out on the slopes. Andrew currently travels between his home in Blue River and Minneapolis for his position in the Army. With each trip back he feels his body more quickly adjust to the altitude changes. Thank you for your service Andrew, and welcome to the community!
Ellie Martini grew up in Richmond, VA and is currently a second-year Physician Assistant student at Drexel University in Philadelphia, PA. She completed her undergraduate degree at The College of William and Mary in Williamsburg, VA where she received her BS in Biology. Before PA school she worked as a rehab tech and medical scribe at an addiction clinic. In her free time she enjoys hiking, biking, group fitness, traveling and spending time with friends and family.
