Category Archives: Altitude Science

Acclimation, Altitude Science, Health, High Altitude, High Altitude Training & Fitness, Mountaineering

Understanding the effects of nocturnal hypoxemia in healthy individuals at high altitude: A chance to further our understanding of the physiological effects on residents in Colorado’s mountain communities

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The population of Summit County, Colorado is projected to grow by 56% between 2010 and 2030. Along with adjacent Park and Lake Counties there are now over 40,000 people living above 2800 meters elevation. This is the largest high altitude population in North America. As opposed to native populations in South America, Africa and Asia who have been residing above 2800 m for centuries, the North American residents are acclimatized but not adapted. Symptoms related to hypobaric hypoxemia are notable above 2500 m.  Recognized conditions associated with altitude include central sleep apnea leading to hypoxemia (abnormally low oxygen level in the blood) which activates the sympathetic nervous system. In susceptible persons this can cause systemic and pulmonary hypertension. The incidence of this potentially devastating side effect of mountain living is unknown.  In order to better understand the potential side effects of nocturnal oxygen desaturation in healthy individuals, it is beneficial to investigate the normal physiological changes that occur during sleep, which leads to low oxygen levels in all individuals.

When the body enters the sleep state, many of the behavioral mechanisms that are active during wakefulness are blunted, and it’s been found that different sleep stages have varying effects as well.  One of the major changes is a diminished response to hypercapnia (high carbon dioxide levels in the blood) and hypoxia.  During sleep, the CO2 set point is elevated from 40 mmHg to 45 mmHg, which results in reduced alveolar ventilation.   It’s also observed that minute ventilation is reduced, which is due to decreased tidal volumes that is normally compensated for with an increase in breathing frequency during wakefulness.  Also, during sleep, there tends to be upper airway narrowing that is normal and there is reduced reflex muscle activation of the pharyngeal dilator muscle.  All of the above factors contribute to decreased ventilation during sleep. 

A lot of what is understood about the effects of nocturnal hypoxemia is due to extensive studies in individuals with underlying diseases, and these studies are not always conducted at higher altitudes.  One such study investigated the effects of nocturnal desaturation (SaO2 < 90% occurring for > 30% of the sleep study) in chronic obstructive pulmonary disease (COPD) patients without a diagnosis of sleep apnea.  The authors found higher rates of dyspnea, increasing rates of worsening COPD symptoms, poorer quality of sleep and health-related quality of life.  Another such study found that some patients with COPD experience increased transient arterial hypoxemia (TAH) during rapid eye movement (REM) sleep.   In this study, the authors observed that the study subjects experienced increased pulmonary vascular resistance (which can lead to pulmonary hypertension) and a few subjects experienced an increase in their cardiac output. The authors found that individuals could experience a decrease in this phenomena by using nighttime oxygen therapy.

Studies, such as above, do not assist in identifying healthy individuals that may need early intervention due to nocturnal hypoxemia at altitude.  What about the healthy individuals without underlying diseases?  In the study conducted by Gries and Brooks in 1996, the authors collected data from 350 patients.  Their recorded average low saturation in the study of 350 subjects was a reported 90.4% lasting an average 2 seconds.  This study was conducted at the Rainbow Babies and Children’s Hospital located in Cleveland Ohio, at an elevation of 653 feet (198 m). This is one of the largest studies done to assess normal oxygen levels observed during sleep, and the results, along with results from other studies are displayed in Table 1.  As of right now, there is no equivolent study for subjects at elevations like that of Summit County, CO, which is at an average of 9110 feet (2777 m). Aside from the normal physiological changes noted above, the rates of developing underlying central sleep apnea leading to systemic and pulmonary hypertension is unknown.  Further, there are no guidelines as to initiating treatment in patients that may be experiencing adverse effects of high altitude nocturnal hypoxemia, because there is a lack of data to establish baseline normal values observed at this elevation.  This leads to unnecessary sleep studies, and further involvement of a myriad of healthcare professionals that have no specific guideline to reference when approached by one of these patients. 

In order to further our understanding of the effects of high altitude and nocturnal hypoxemia in healthy individuals, like that of Summit County, there has to be preliminary and ongoing research in these individuals.  Dr. Chris Ebert-Santos is currently conducting an overnight pulse oximetry study, which aims to recognize which symptoms they may or may not be experiencing, that are related to high altitude or sleep disorders, so that they may receive treatment, feel better, and remain active. 

At this moment, initial study results reveal a decreased average low night oxygen saturation from that of the study conducted by Gries and Brooks.  In a sample of just 14 individuals, the average low SpOs recorded overnight is at 81.3%, which is 9% lower than that recorded by Gries and Brooks (Graph 1).  The study is also revealing a trend in lower night oxygen saturations in individuals that have lived at elevation for a longer period of time (Graph 2). These findings suggest the need to expand and build on the current study being conducted by Dr. Chris and her team at Ebert Family Clinic. If interested, you may apply in-person at Ebert Family Clinic, where you will be required to fill out a health questionnaire on your length of residence at altitude, medical history, and possible symptoms related to high altitude.  Your basic vitals will be logged at the appointment.  After the first study, you will then be rescheduled in 12 months for a follow-up overnight study to monitor for any changes.  Overall, this study is designed to help with an understanding on the potential impact of high altitude on healthy individuals that are acclimated, but not necessarily adapted, to this environment.

Robert Clower is a second year physician assistant student at Red Rocks Community College in Arvada, CO.  His undergraduate degree was in Biology, which incorporated both medical health science courses as well as independent research courses in general biology and ecology.  While attending school at the University of North Georgia, Robert served in the Army National Guard for a cumulative time in service of 8 years.  After completing his undergraduate degree, Robert gained medical experience as an operating room assistant, which included assisting support staff with surgical preparation and patient transport throughout the hospital for surgical appointments.  Outside of his studies, Robert enjoys snowboarding, hiking, snowshoeing, exercising and spending time with family and friends. 

Sources

Summit County Population Projections: Summit County, CO – Official Website. Summit County Population Projections | Summit County, CO – Official Website. http://www.co.summit.co.us/519/Population-Projections. Accessed March 3, 2020.

Tintinalli JE, Ma OJ, Yealy DM, et al. Tintinallis Emergency Medicine: a Comprehensive Study Guide. New York: McGraw Hill Education; 2020.

Gupta P, Chhabra S. Prevalence, predictors and impact of nocturnal hypoxemia in non-apnoeic patients with COPD. 52 Monitoring Airway Disease. 2015.

Lemos VA, Antunes HKM, Santos RVT, Lira FS, Tufik S, Mello MT. High altitude exposure impairs sleep patterns, mood, and cognitive functions. Psychophysiology. 2012; 49 (9): 1298-1306.

Cingi C, Erkan AN, Rettinger G. Ear, nose, and throat effects of high altitude. European Archives of Oto-Rhino-Laryngology. 2009; 267 (3): 467-471.

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

Altitude Training 101

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High elevation prompts physiologic changes in the body. As elevation increases, oxygen concentration in the air decreases; this is why some people suffer from altitude sickness when travelling to high altitude environments like Summit County, Colorado from a lower elevation. Training and/or living at elevation increases our red blood cell mass in order to compensate for the lower oxygen concentration, thus increasing our oxygen-carrying capacity. Red blood cells are like microscopic rafts that flow down the rivers of our blood vessels, picking up oxygen from our lungs when we breathe and then transporting it to all the muscles and organs that need it to function properly. For athletes, this physiologic concept can be used to their advantage in order to improve their performance. If they can train their blood cells to carry more oxygen by forcing them to grow in a more hypoxic (low-oxygen) environment, then they can have more oxygen available to their muscles to perform in any activity.

There is a modern training model that some athletes have adopted called “Live High, Train Low”. This means that the athlete performs high intensity training sessions at a lower elevation, but maintains general training and living at higher altitude. Your body begins making metabolic changes immediately when exposed to high altitude and hypoxia, but it can take a couple weeks for the maximum effect. Expert Dr. Gustavo Zubieta-Castillo, who spoke in La Paz, Bolivia at the 7th Annual Chronic Hypoxia Conference that Dr. Chris attended in 2019, claims that it takes him about 40 days to build up his hematocrit to be back to functional in La Paz which is situated at nearly 12,000 ft. All in all, the goal of living and/or training high, while including high intensity sessions at lower altitude, is to give your body enough time to build up some acclimatization to the hypoxic environment. Several studies in the last 25 years have taken various groups of athletes and placed them on different training regimens over 4 weeks. Some would live at low altitude and also train low, some trained low and lived high, and others trained high and low while living at high altitude. One study completed in 2008 concluded that athletes who either live high and train low, or live high while training low and high, showed about a 1.4% improvement in sea level endurance performance.

How high is too high, and how low is too low?

Snowshoeing above 9000 ft., Summit County, Colorado.

It was found in this same study, that there is in fact a “sweet spot” for implementing the “Live High, Train Low” paradigm. If subjects were living lower than 1800 m, there was not a significant improvement in athletic performance. On the other hand, if subjects were living too high, they could not adequately recover from training and therefore did not show improvement because their bodies struggled to keep up with the hypoxic environment. The best elevation to live and/or train at in order to increase RBC (red blood cell) production, RBC mass, and oxygen-carrying capacity is between 2100 m-2800 m, or about 7000 ft-9000 ft.

What does this mean for athletes in Summit County who live high and train high?

Great news! There are still major benefits to those who live and train in Summit Country, as well as for people who visit the mountains and train while they are in town. This is because of a physiologic process called autophagy. Autophagy is described as our cells’ process of degrading old proteins and damaged cell parts. This is a normal process that modulates cell survival, is important for cell renewal, and is also a promoting factor of exercise performance from altitude training.

When exposed to a hypoxic environment, our cells produce adaptive responses that ramp up autophagy and cell renewal elements. These responses include factors that promote skeletal muscle growth, boost skeletal muscle capillary concentration, and enhance coronary arteries (the arteries that feed your heart). Living and training at altitude is good for your heart and it can help build muscle while decreasing body fat mass. It also shows significant increase in cardiac output and strength of your heart stroke.

However, excessive exercise and especially excessive exercise at altitude can prove harmful to our skeletal muscle. It has been observed in male subjects running 20 km that the excessive exercise induces autophagy too much which leads to degradation of muscle protein, damage, and eventual loss of skeletal muscle all together. Therefore, just as there is a sweet spot for altitude training, it is also a good idea to monitor training in order to maximize the benefits of training in a place like beautiful Summit County.

So, how should I be training if I live in Summit County or if I am visiting for some time?

I had the pleasure of speaking with Mary Scheifley about this particular strategy. Mary is the owner of Peak One Fitness, a 24-hour gym in Frisco, Colorado (9000 ft.). She has over 20 years of experience in fitness and athletic training. She competed semi-professionally in mountain bike racing, and continues to bike today as well as cross-country ski, snowboard, weightlift, hike, and anything else that keeps her active. She loves Frisco and has found that being outside and active is almost spiritual. She is passionate about fitness and nutrition, and she works extremely hard to tailor her training regimens to each of her clients based on their individual needs or goals.

Cardio machines at Peak One Fitness, Frisco, Summit County, Colorado

When she trained people in Denver, she typically was running high-intensity aerobic classes. However, here in Frisco, she prefers to focus on strength and only include high-intensity interval training (HIIT) in short spurts. She believes that you don’t need to be over-exerting your body to see a positive response. She has a client who lives near sea level for most of the year where her main training regimen includes Cross Fit. When she comes to Frisco though, she can see a significant decrease in BMI and body fat index in just two months of lower-intensity training. Though frustrated that she cannot run on the treadmill as fast or as long as she can at home, by the end of her stay in Frisco, this client understands that difference of the elevation and appreciates the process that Mary provides for her.

Mary recognizes that fitness is not “one size fits all”. She typically likes to start people out at 80% of their maximum heart rate when exercising, but there are factors that may change this. Her clients that live in Summit County have already been acclimatized to the elevation so she can add a little to their 80% max heart rate because for them, 80% may feel like 70%. On the flip side, if you are visiting from sea level, she may have to decrease your 80% of maximum because of the hypoxia at elevation. Other factors that play a role in how Mary develops her training regimens include age, the client’s goals, their previous fitness level, and their overall reaction to altitude.

I also asked Mary about her experience with competition and professional athletes. Personally, she could tell that her endurance was superior to her competition when she raced at altitude against bikers from Denver. She also noticed that when she was in Denver, the racers there were stronger and bulkier than her. She also has experience training athletes who are preparing for competitions such as the Leadville 100 or who are professional skiers who tell her that it is more beneficial for them to come to altitude about 3 weeks prior to competition in order to prepare rather than just training at lower altitude. This is because their body will better adapt if they give it a little more time before competition while training.

At the end of the day, whether you are training for a competition, or just trying to stay healthy, being at altitude can pose challenges as well as benefits to our bodies. The following are some tips from Mary on maximizing your workouts at altitude without compromising your health and wellness.

Mary’s tips for athletic training and exercising at high altitude:

  • Increase water intake, even before you come to elevation. You should be drinking at least 3-4 liters of water per day.
  • Increase caloric intake. At altitude you are burning more calories than at sea level, and if you are wanting to train you need to fuel your body appropriately. Especially increase protein intake.
  • No alcohol. If you enjoy one drink here and there you should be fine, but if you are wanting to train at a high level alcohol should not be on the menu.
  • Add electrolytes. In addition to increasing water, you need to make sure you are replenishing your body with the salts it requires.
  • Take it slow. Maybe start with some yoga or moderate stretching before moving into running or HIIT classes. You may need to decrease your level of training by 20%.
  • Consider spending a night in Denver before heading up the mountain to Summit County. Dr. Chris has expressed this frequently to travelers and visitors of Frisco; it gives your body a chance to acclimatize prior to ascending to 9,000+ feet.
  • Don’t expect to be at your “home” level of endurance or fitness. Do not get discouraged if you cannot run your typical 7-minute mile, or you can’t easily warm up with a set of 10-15 squats. Your body needs to adjust, and you may need to just take it easy in the altitude. Ultimately, have fun and enjoy the beautiful outdoors!

Sarah Brzecezk is a 2nd year Physician Assistant student attending Midwestern University in Glendale, Arizona. She graduated from Northern Arizona University in Flagstaff, AZ with a Bachelor’s in Biomedical Sciences and then worked as a medical assistant in Internal Medicine prior to starting PA School. She is passionate about healthy eating and maintaining a physically active lifestyle, and she hopes to specialize in Orthopedics when she graduates this Fall. During her 6 weeks at elevation in Frisco, Colorado, she has enjoyed numerous hikes, two hut trips, yoga classes, and running in the gorgeous outdoors. Her goal as a provider is to help others overcome injury and illness in order to return to physical activity and athletics, enabling them to combat chronic illness and stay healthy for their future years.

References

Zhang, Y., & Chen, N. (2018). Autophagy Is a Promoter for Aerobic Exercise Performance during High Altitude Training. Oxidative medicine and cellular longevity, 2018, 3617508. doi:10.1155/2018/3617508

Brocherie, F., Millet, G. P., Hauser, A., Steiner, T., Rysman, J., Wehrlin, J. P. & Girard, O. (2015). “Live High–Train Low and High” Hypoxic Training Improves Team-Sport Performance. Medicine & Science in Sports & Exercise, 47(10), 2140–2149. doi: 10.1249/MSS.0000000000000630.

Stray‐Gundersen, J. and Levine, B.D. (2008), Live high, train low at natural altitude. Scandinavian Journal of Medicine & Science in Sports, 18: 21-28. doi:10.1111/j.1600-0838.2008.00829.x

Acclimation, Altitude Science, Asthma, Child Growth & Development, Doc Talk, Health, High Altitude, Medicine

Dr. Chris’s HAPE Cheat Sheet

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Inflammation and altitude can cause low oxygen. Inflammation is commonly caused by viral infections such as colds or influenza, but can occasionally occur with bacterial infections such as strep throat or pneumonia. Low oxygen, or hypoxia, is the result of fluid collecting in the air sacs of the lungs, called pulmonary edema.

There are three types of high altitude pulmonary edema (HAPE).

  1. Classic HAPE, recognized for over a century. occurs in visitors to altitudes above 8000 ft (2500m) beginning during the first 48 hours after arrival. Symptoms include cough, congestion, trouble breathing, and fatigue, all worse with activity.
  2. Re-entry HAPE occurs in people who are living at altitude, travel to lower altitude, and develop symptoms during the first 48 hours after returning home
  3. High Altitude Resident Pulmonary Edema (HARPE) is a recently recognized illness that occurs mostly in children who have an underlying respiratory illness and live at altitude, with no recent history of travel. They have oxygen levels below 89 and lower but do not appear toxic. They are fatigued but rarely have increased work of breathing.
Parents are often worried their children won’t wear a canula for oxygen, but they don’t typically mind.

Treatment of HAPE is oxygen. There may also be signs of asthma or pneumonia which are treated with bronchodilators and antibiotics. Most people with pneumonia at altitude do NOT have hypoxia. All three types of HAPE can reoccur, but typically not with every arrival at altitude or viral illness. Many of these patients are told they have pneumonia again and again, or severe asthma, and are treated with inhalers and steroids. Usually, this adds nothing to their recovery.

A chest x-ray may show typical infiltrates seen with pulmonary edema, but in mild or early cases, can look normal. There is no blood test for HAPE. Oxygen should be used continuously at a rate that raises the oxygen saturation into the 90’s. Length of treatment may be as short as 2 days or as long as ten days

Most importantly, owning a pulse oximeter and measuring oxygen levels in anyone at altitude with symptoms of cough, congestion, fatigue and trouble breathing with exertion can keep people out of the ER and ICU. HAPE can rapidly progress to respiratory failure and death if not recognized and treated expediently.

Acclimation, Altitude Science, Health, High Altitude

Effects of High Altitude on Appetite and Weight Loss

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It’s no secret that people living in high elevation areas such as Summit County seem to be healthier than the general population. But aside from the active lifestyles of many people who choose to live in the mountains, could there be other effects from living at high altitude that result in healthier outcomes?

Several studies have been conducted to examine the association between living at high altitude and weight loss. The overall findings suggest simply ascending to a higher altitude generally results in a reduction of weight. Whether this is due to relative low pressure hypoxia or increased physical activity is another question examined by researchers. Overall, a higher energy expenditure and decreased appetite have both been seen in those living at higher altitudes. One study found that those living below 500 m elevation on average had a 4.6 times higher risk of obesity compared to those living above 3000 m while controlling for differences in exercise, diet, and lifestyle.

Leptin is a hormone produced by the body that results in suppression of hunger. When our bodies secrete more leptin our hunger decreases. Multiple studies have shown that when people not acclimated to altitude are brought to higher elevation, leptin increases and appetite decreases. One such study took ten obese males to altitude and allowed them to eat as much as they would like and also did not allow them to exercise more than their regular amount during the study. After one week the study found the males consumed on average 730 calories less than what they usually ate at lower altitude. This resulted in a 3 pound weight loss over one week, and on average, they kept two pounds off after returning to their base altitude a month after the one week study was completed.

Leptin levels were increased for a time after returning to lower elevation and appetite remained lower than their baseline.

A follow-up study looked to determine exactly what factor of altitude causes this increase in leptin and used a hypobaric chamber to simulate a hypoxic environment similar to Mt. Everest. Subjects in this experiment lived in low oxygen conditions for 40 days and had an average of 16.7 pounds of weight loss and consumed 1,347 fewer calories. This study helped to suggest hypoxia as the driving factor for increases in leptin at altitude, and also showed an increased effect with the higher elevations.

Another possible factor leading to higher rates of weight loss at altitude could be linked to an increase in basal metabolic rate. Basal metabolic rate, or BMR, is the amount of energy or calories humans burn each day without accounting for exercise or general physical activity. In the same study that measured appetite and leptin levels in obese men brought to altitude for one week, BMR was also measured. These measurements showed an increased BMR at the end of one week at altitude and a return to baseline BMR two weeks after returning to lower altitude. This means that people tend to burn more calories just by being at a higher altitude, even without increasing exercise. This increased burning of calories paired with decreased appetite are likely the main driving forces between the weight loss seen in those newly introduced to altitude and lower weights and BMI’s seen in those that have lived at altitude for a long time.

With these findings of weight loss and overall decreased appetite when coming to altitude, it is important for visitors from low altitudes to be aware of these changes and plan appropriately. First of all, in order to avoid unintended weight loss, those new to the mountains should be aware of just how much they are eating. Apps such as MyFitnessPal are great for tracking your calories and can even factor in exercise such as hiking and skiing that may be causing you to burn extra calories. Based on your BMR and exercise, you can see just how many calories you should be eating to maintain your current weight. It is also essential to be aware of the kinds of food you are eating. In the studies showing decreased appetite, it was also shown that study subjects had a decreased likelihood of choosing carbs in their diet. Carbohydrates are an excellent source of energy and should be a main staple of the diet for anyone coming to altitude, especially if they plan to partake in any of the great outdoor activities places like Summit County have to offer. Good examples of healthy carbs include fruits, vegetables, nuts, and whole grains like quinoa, oats, and brown rice.

Ultimately, ascent to higher altitudes has been shown to cause a decrease in appetite, increase in basal metabolic rate, and an overall decrease in body weight. Some of these factors return to closer to baseline after acclimatization, but this can take weeks to months depending on the person. Anyone who is traveling to higher altitudes or who has recently moved to a higher altitude should take good notice of their general nutrition and calorie intake to make sure they are giving their body the fuel it needs to succeed in these unique conditions.

Mitch Tiedke is a physician assistant student at the Red Rocks PA Program in Arvada, Colorado. He grew up in Oak Grove, Minnesota and achieved his undergraduate degree in Genetics, Cell Biology, and Development, with a minor in Public Health from the University of Minnesota-Twin Cities. He has previously worked as a personal care assistant for developmentally delayed adults and as a nursing assistant on a pediatric oncology, GI, and med/surg inpatient unit. In his free time he enjoys hiking, snowboarding, biking, and movies.

References

Buchzik, B. (2014). Hypobaric hypoxia causes body weight reduction in obese males, double-blinded, placebo-controlled study. European Respiratory Journal, 44(58). Retrieved from https://erj.ersjournals.com/content/44/Suppl_58/P3650.short

Lippl, F. J., Neubauer, S., Schipfer, S., Lichter, N., Tufman, A., Otto, B., & Fischer, R. (2010). Hypobaric Hypoxia Causes Body Weight Reduction in Obese Subjects. Obesity, 18(4), 675–681. doi: 10.1038/oby.2009.509

Palmer, B. F., & Clegg, D. J. (2013). Ascent to altitude as a weight loss method: The good and bad of hypoxia inducible factor activation. Obesity, 22(2), 311–317. doi: 10.1002/oby.20499

Rose, M. S., Houston, C. S., Fulco, C. S., Coates, G., Sutton, J. R., & Cymerman, A. (1988). Operation Everest. II: Nutrition and body composition. Journal of Applied Physiology, 65(6), 2545–2551. doi: 10.1152/jappl.1988.65.6.2545

Voss, J. D., Masuoka, P., Webber, B. J., Scher, A. I., & Atkinson, R. L. (2013). Association of elevation, urbanization and ambient temperature with obesity prevalence in the United States. International Journal of Obesity, 37(10), 1407–1412. doi: 10.1038/ijo.2013.5

Acclimation, Altitude Science, Health, High Altitude, Medicine, Surgery

Increased Risks of Orthopedic Surgery at Altitude

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With orthopedic surgeries becoming more common at higher altitudes, it is important that we understand the increased risks of surgery at higher elevations. Patients locally (Eagle, Summit, Pitkin, Grand, Lake and other high-altitude counties in Colorado) and those that travel from all over the world to undergo surgery by our orthopedic surgeons are at an increased risk for complications post-surgery. Patients that have surgery at a lower altitude and return to higher elevations post-surgery are also at higher risk for post-operative complications. These risks are higher for everyone having surgery at altitude regardless if you live at higher elevations or are from sea level.

High altitude is defined as 8-12,000 feet. However, increased surgical risks are seen starting at 4000 feet. There are no differences for increased risk if you are acclimated to the altitude (live here) or are visiting. The increased risk of surgery at high altitude is the same for all.

High altitude increases the coagulation state of blood (clotting ability) and hyperventilation (breathe out more than you breathe in), and oxygen saturation of blood and tissues is 10% lower at high altitude compared to low altitudes, leading to a hypoxic state. The hyperventilation state promotes the hypercoagulable state which causes the immune system to respond with a pro-inflammatory state. Acclimation does occur, we adapt, are able to breathe easier and function normally as our bodies make more red blood cells to compensate for the lower available oxygen in the air. However, the hypercoagulability of blood remains, because the hyperventilation state is sustained at high elevations (even if you live here). At high elevations there are physiological differences in pulmonary circulation (blood through the lungs), heart function, and fluid imbalances which induce dehydration that accompanies blood changes contributing to the increased risk of surgery at high elevations.

Risk factors for blood clots from orthopedic surgery for the general population include: decreased mobility or sitting around more, length of surgery (greater than 4 hours increases blood clot risk), joint replacements, smoking, diabetes, and other illnesses.

In general, there is a 40-60% chance of a blood clot following knee or hip replacement surgery. At altitude that risk doubles. There is a 3.8 times greater risk of thromboembolism (blood clots) for knee surgeries at high elevations. Total shoulder replacement surgery also demonstrates a 2-times greater risk of pulmonary embolism at altitude or 39.5%, compared to a 15% chance at sea-level. For rotator cuff repair of the shoulder, there is also an increased risk for blood clots. There is a 1.4-times greater risk for pulmonary embolism (blood clot in the lungs) for lumbar fusions at high altitude. Higher elevation is an independent risk factor for blood clots which lasts up to 90 days post orthopedic surgery.

Anesthesia at high altitude has its own risk. The sustained hyperventilation state at high altitude also leaves the patient more vulnerable to hypoxia and pulmonary edema with anesthesia. These risks can be minimized, however remain elevated for surgeries requiring general anesthesia above 4000 feet.

For patients returning to high altitude following surgery at lower elevations, there exists multiple risks due to hypercoagulable state, increased inflammatory response, and hyperventilation that higher elevations induce. Acclimatization to high altitude is lost within 2 days of being at a lower elevation and can take 3-4 months to achieve again. In as little as 2 hours after arriving at high altitude, the body initiates the above changes and this puts the post-operative patient returning to altitude at risk for a multitude of complications: dehydration, thromboembolisms, hypoxia, atelectasis, and pulmonary edema.

I recently spoke with a patient that grew up in Leadville (10,151 feet) and lives in Summit County (average of 7947 feet). She underwent hip surgery (twice) in Denver. Upon returning to Summit County, she developed high altitude pulmonary edema (HAPE) both times. When she underwent an ankle surgery in Edwards, the surgeon prophylactically treated her for high altitude sickness given her previous history. She did not develop HAPE, but was hypoxic and required oxygen therapy following surgery for a few days. She is a prime example that even those living their entire lives at altitude are susceptible to these increased risks from surgery.

These risks can be minimized by drinking plenty of fluids, using compression socks (TED hose) or sequential compression devices (SCDs), blood thinners (aspirin, Eliquis, or the like), doing ankle pumps and glute squeezes, and getting up and walking around every 1.5-2 hours for 10-15 minutes, all of which help decrease the likelihood that patients will experience blood clots following orthopedic surgeries.

To reduce respiratory or lung related complications it is important to do deep breathing exercises or incorporate the use of an inspirometer post-surgery, use supplemental oxygen if necessary, as well as continue to do these exercises after returning from a lower elevation for at least 2-3 weeks.

High altitude is an independent risk factor for orthopedic surgery complications. However, these increased risks have been seen in trauma patients and other surgical patients as well. The hyperventilation state, hypercoagulability, and elevated inflammatory response are not isolated to orthopedic patients, but exists in everyone living at and visiting higher elevations.

— Jessica Guthrie, BSN, RN

References

Cancienne, J., Diduch, D., & Werner, B. (2017). High altitude is an independent risk factor for postoperative symptomatic venous thromboembolism after knee arthroscopy: A matched case-control study of Medicare patients. Arthroscopy: The Journal of Arthroscopic and Related Surgery 33(2). https://dx.doi.org/10.1016/j.artho.2016.07.031

Damodar, D., Donnally, C., Sheu, J., Law, T., Roche, M., & Hernandez, V. (2018). High altitude an independent risk factor for venous thromboembolisms after total hip arthroplasty. Journal of Arthroplasty 33(8), 2627-2630. https://doi.org/10.1016/j.arth.2018.03.045

Damodar, D., Vakharia, R., Vakharia, A., Sheu, J., Donnally, C., Levy, J., Kaplan, L., & Munoz, J. (2018). A Higher altitude is an independent risk factor for venous thromboembolisms following total shoulder arthroplasty. Journal of Orthopedics 15(4). https://doi.org/10.1016/j.jor.2018.09.003

Donnally, C., Vakharia, A., Sheu, J., Vakharia, R., Damodar, D., Shenoy, K., & Gjolaj, J. (2019). High altitude is an independent risk factor for developing pulmonary embolism, but not a deep vein thrombosis following a 1 to 2 level lumbar fusion. Global Spine Journal 9(7) 729-734. https://doi.org/10.1177/2192568219828349

Tyson, J., Bjerke, B., Genuario, J., & Noonan, T. (2016). Thromboembolic events after arthroscopic knee surgery: Increased risk at high elevation. Arthroscopy: The Journal of Arthroscopic and Related Surgery 32(11), 2350-2354. https://dx.doi.org/10.1016/j.arthro.2016.04.008

Wani, Z. & Sharma, M. (2017). High altitude and anesthesia. Journal of Cardiac Critical Care 1(1), 30-33. https://doi.org/10.1055;s-0037-1604203

Acclimation, Alcohol at Altitude, Altitude Science, Doc Talk, Health, High Altitude, Medicine

Doc Talk: The Art of Saving Vacations

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In 1986, Dr. David Gray was asked to join a team of rafters on an exploration of the Yangtze River in China. Their goal, simple: to reach the undiscovered source of the Yangtze river and raft all the way down. Although simple is quite the understatement. The Yangtze River is the 3rd longest river in the world, and the source of the river is at approximately 19,000 feet (5791 m) above sea level. 

Dr. Gray, a young physician at the time, agreed to join the mission after being told by the mission frontman, Ken Warren, that “we want you there for trauma”. Dr. Gray, however, had an inkling that the high elevation could present some interesting challenges. He consulted with two pulmonologists, but at the time, understanding of treatment at high altitude was limited–he got little advice. With eagerness and reassurance that he would “have the final say on all things medical”, he began the mission. 

The team was comprised of an eclectic group of gentlemen. From 4 Chinese Olympic athletes, to a camera man from National Geographic, the crew set forth to uncharted territory. The took a bus up the first 14,000 ft, and they learned quickly about the effects of altitude. “Everyone was sick. I’m treating headaches with narcotics, treating vomiting with phenadrine, and guess what I had for pulmonary edema: lasix!” Despite the chaos, everybody improved and the crew trudged forward. 

In their slow ascent, there came a point when the snow was nearly six feet deep — vehicles were no longer an option. The rest of the mission would be on foot. On foot, with yaks carrying their gear, the crew moved up the glacier to what they presumed was the source of the river. The photographer from National Geographic, David Schippe, had not been doing well. As the mission progressed, Dr. Gray could hear crackles in the base of his lungs through a stethoscope and sent him down to receive medical attention. This was a case of  high altitude pulmonary edema (HAPE); he was diagnosed with pneumonia.

The rest of the crew reached the presumed source, “Tigers Leak Gorge”, which turned out to be one of the many Yangtze tributaries. On their decent down on “duckies”(blow-up rafts), they stopped at base camp and found David Schippe, the photographer that was supposed to have headed back to receive medical care. Their next checkpoint was at 11,000 ft; it was 600 miles away and they had no choice but to continue down with Schippe alongside. 

Unfortunately, this would be David Schippe’s last journey. “On the second day, Schippe started coughing; he gets very sick, and is put on IV. I said, ‘we need the helicopter,’ but there was no helicopter; that was all a lie. [Ken] had a short-wave radio, but he used the money for the emergency helicopter to pay his mortgage.” Dr. Gray, feeling the weight of this terrible deception, knew this would be the end of Schippe’s life.

We buried him on the river.

Dr. Gray distinctly remembers Ken Warren, the expedition leader’s announcement of their crew member’s death.

He said, ‘Dave’s dead. Suck it up, or you could be next.’

That was confirmation to Dr. Gray that this mission was not being run with any regard for crew safety. When they got to their checkpoint, Dr. Gray said “adios”. 

And so went Dr. Gray’s introduction to Altitude Medicine.

Fast forward to today, in a local brewery, Dr. Gray, equipped with the wisdom of 20 years of practice in Summit County, Colorado, after 25 years of Emergency Medicine in Corpus Christi, Texas, shares some of the essential knowledge for working in the hypoxic conditions of high altitude. An advocate for accessible and affordable health care, much of his practice involves bringing his medical services straight to his patients.

Has anything changed about what you put in your medical bag since you first started doing mobile health care?

No. I had a select group of medications I use that cover almost everything. I get an antibiotic prescription, so I can hand them their ZPak (my “go-to” medication).  I carry ventil, decadron, nubain (a synthetic narcotic) — it has some narcotic antagonist effects, so you have to be careful if you put someone on opioids on it, because it’ll put them in immediate withdrawal — Benadryl, and epinephrine.

First case of HAPE in Summit County?

He was from Scotland or somewhere in the British Isles. I sent him to the hospital, he gets in the ambulance, spends two days in the ICU in Denver, and $30K later, they send him back up!

Dr. Chris mentions that even physicians in Denver aren’t always familiar with high altitude care, and can order extensive testing for symptoms that are classic presentations of high altitude pulmonary edema. 

I got a guy from Austin; he was in his late 40’s. He had pulmonary edema, and  his O2 sats were maybe in the 70s. I said, ‘you need to go to the hospital, get out of the altitude, and go to Denver.’ He said, ‘I don’t want to leave my family, do I have to leave?’

I told him, ‘I’m going to work with you, but you have got to do everything I say. I’ll be back in the morning to give you another dose of decadron and you don’t get to sue me if this doesn’t end well.’

I see him the next day, give him another shot of decadron. He was one of the first people I allowed to stay at altitude. I wouldn’t leave anybody with that treatment if I couldn’t get him up to the high 70s.

Dr. Gray typically puts these patients on oxygen full-time at approximately 5 liters, monitors them closely, and finds patients’ oxygen saturations will typically go up into the 90’s.

I got confident with what I was doing.

He also makes a point that it’s essential to re-check vitals in these patients and to pay attention to symptoms. Too often, patients present with an acceptable oxygen saturation, around 93, and end up coming back hypoxic:

The oxygen can present normal initially because patients are hyperventilating! The respiratory muscles cannot maintain that work of breathing, and later, their oxygenation will drop! 

Dr. Gray and his own family have had their own experience with re-entry HAPE, as well:

We were back in Texas for a few weeks. I took them to the [alpine slide] back in Breckenridge, and Dillon (Dr. Gray’s son), who always got headaches, comes up to the car and throws up a bunch of red vomit. I told his sister, ‘Please tell me he drank a red soda before this.’ (He had.) Then we go home and he’s just feeling bad. I just figured, it’s his headache, or it’s a viral bug, then luckily, I put him in bed with me. At about 10 pm that night, he was coughing so much it was keeping me up. I put a stethoscope on him, and it was like a washing machine! His oxygen was 38!

I put him on five liters of oxygen and he quit coughing. The cough reflex was there because the lungs were trying to do anything to get more oxygen!

It’s not that the pulmonary edema was getting better quickly, necessarily; it took about three days for him to get better.

“It ain’t about water; it’s diet.”

What I believe happens when you come two miles in the sky as abruptly as people do: most Americans are dehydrated anyways. When they get here, the body goes into defense mode. It shunts blood and oxygen into your heart and kidneys and consequently … away from your stomach. Then, they (visitors) eat restaurant portion meals and greasy steaks on vacation. That’s why vomiting is sometimes the primary symptom. 

What I tell people is if you stop in a restaurant on your way up here, choose high carb, low fat, low protein meals — carbs are easy to transport through the system. Choose smartly, eat half of what they put on your plate, and take the rest home. The last meal should be at 5 pm. 

Also, alcohol is a mild diuretic at best! The real issue is that it’s a respiratory depressant! If you need to drink on this trip, drink in the morning!

Who gets acute mountain sickness? 

Young fit males. They come up here with a resting pulse of 52 beats per minute. A well-exercised person can’t get their heart rate up to counteract hypoxia. Then they ignore their symptoms because that’s what athletes do. As for athletes, I’ve given up on that. They go 100%, and they are not going to hold back.  

Another point that Dr. Gray emphasized was the seasonal factors: 

We see a marked difference in acute mountain sickness in Winter and Summer. You are by necessity in a hyper-metabolic state in the cold. Your body is working hard using oxygen to stay warm.  Plus, people are overusing muscles they haven’t used all year. In the summer, they come up in cars and ‘meander’ up. In the winter, they fly and ascend within hours. [Ages ago], you didn’t see any altitude sickness because they came on donkeys! Very slowly! 

And if you’re not sick by day two, you probably won’t be.

By the age of 50:

Everyone who lives here should sleep on oxygen. If you haven’t been here for generations, you need to be on night time supplemental oxygen. The only exception to this is in COPD patients due to oxygen deprivation driving respiration and CO2 retention.

I tell full-time residents, ‘you need an oxygen concentrator.’ It’s a night time problem. During the day, you’re ventilating. At night, you go into a somnolent state and your breathing goes down.

Muscles are healthier when you use them, that goes for the heart too. We (Summit county residents) are hyper-dynamic, cardiac-wise. If you supplement with oxygen at night, you keep the process of pulmonary hypertension from developing. 

Advice to the Traveler

Diamox: it changes your acid base chemistry, acidifying your serum, which, essentially, turns you into your own ventilator. Some people are aware of their increased respiratory depth and it may bother them. 125 mg twice a day, beginning two days before travel. Any dose greater than that will just increase side effects. 

The Water Issue: you can’t make up for chronic dehydration during the day. The biggest loss of fluid from the human body is insensible loss – moisturizing the air you breathe! Altitude also produces diarrhesis, as well as a lot of intestinal gas. The poor bacteria in your GI are also hypoxic.

Talking Altitude Medicine with Dr. David Gray

Dr. Gray opened his own practice in Breckenridge, CO caring primarily for travelers. With the motto “We save vacations,” he expresses a true passion for the demographics of the population and practice at high altitude. He developed his practice by networking closely with local ski industry workers, from lifties to ski shop employees, and provides fee for service immediate care to his patients. 

Autumn Luger is a physician assistant student at Des Moines University. She grew up in the small town of Bloomfield, Nebraska where the population of cattle vastly outnumbered humans. From there, she moved on to study biology and chemistry and eventually receive her bachelor’s degree at the University of Sioux Falls in South Dakota. She enjoys leisurely running, competitive sports, hikes in beautiful locations, attempting to bake, thrift shopping, and expressing creativity through art. Since being in Summit County, she has discovered some new interests as well: snowshoeing, hot yoga, and moonlit hikes.

Acclimation, Alcohol at Altitude, Altitude Science, Doc Talk, Genetics, Health, High Altitude, High Altitude Training & Fitness, Medicine, Mountaineering

Doc Talk: Nutrition & Oxygen as Preventative Medicine

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Dr. C. Louis Perrinjaquet has been practicing in Summit County, Colorado’s mountain communities since the 80’s, when he first arrived as a medical student. He currently practices at High Country Health Care, bringing with him a wealth of experience in holistic and homeopathic philosophy, such as transcendental meditation and Ayurvedic medicine, as well.

This past week, Dr. Chris managed to sit him down over a cup of coffee in Breckenridge to talk Altitude Medicine. And not a moment too soon, as PJ is already on his way back to Sudan for his 11th trip, one of many countries where he has continued to provide medical resources for weeks at a time. He’s also done similar work in the Honduras, Uganda, Gambia, Nepal, and even found himself out in the remote Pacific, on Vanuatu, an experience overlapping Dr. Chris’s own experience spending decades as a physician in the Commonwealth of the Northern Mariana Islands.

Experience is everything when it comes to High Altitude Health. I asked PJ if there was any such thing as a “dream team” of specialists he would consult when it came to practicing in the high country: more than any particular field, he would prefer physicians with the long-served, active experience that Dr. Chris has in the mountain communities.

Complications at altitude aren’t always so straight-forward. Doc PJ sometimes refers to the more complex cases he’s seen as “bad luck”, “Not in a superstitious way,” he explains, but in “a combination of factors that are more complex than we understand,” not least of all genetics and hormones.

At this elevation (the town of Breckenridge is at 9600’/2926 m), he’s seen all cases of High Altitude Pulmonary Edema (HAPE): chronic, recurring and re-entry. The re-entry HAPE he sees is mostly in children, or after surgery or trauma, which Dr. Chris speculates may be a form of re-entry HAPE.

He’s seen one case of High Altitude Cerebral Edema (HACE), a condition more commonly seen in expeditions to even more extreme elevations (see our previous article, Altitude and the Brain). In this case, “a lady from Japan came in with an awful headache, to Urgent Care at the base of Peak 9 … she lapsed into a coma, we intubated her, then flew her out.”

How common are these issues in residents?

It’s probably a genetic susceptibility. More men come down with HAPE at altitude, or estrogen-deficient women. Estrogen may protect against this. When I first moved up here, we used to have a couple people die of HAPE every year! The classic story is male visitors up here drink on the town after a day of skiing, don’t feel well, think it’s a cold, and wake up dead. A relatively small number of the population up here has been here for decades. Most move here for only 5 – 10 years; even kids [from Summit County] go to college elsewhere, then move away.

In addition to hypoxia, severe weather and climate are also associated with extreme elevation. Do you observe any adverse physiological responses to the cold or dryness, etc. at this elevation?

Chronic cold injury probably takes off a few capillaries every time you’re a little too cold.

At this, Dr. Chris chimes in, “People who have lived here a long time may have more trouble keeping their hands and feet warm.”

Do you have any advice for athletes, or regarding recreation at altitude?

Don’t be an athlete up here very long. Don’t get injured. You can train yourself to perform a certain task, but that might not be healthy for you [in the long term]. Really long endurance athletes – that might not be good for your health, long-term. I see chronic fatigue often, they kinda hit a wall after years: joint issues, joint replacement, …

We’re observing a relatively recent trend with many high altitude and endurance athletes subscribing to a sustainable, plant-based diet. We’ve also encountered a lot of athletes consuming vegetables and supplements rich in nitrates to assist with their acclimatization. Do you have any experience with or thoughts on these techniques?

Eat a lot of fruits and vegetables, not a lot of simple carbohydrates, not a lot of refined grains. Eat whole grains. I’ve been vegan for a while; it’s been an evolving alternative diet.

Do you ever recommend any other holistic or homeopathic approaches to altitude-associated conditions, healing or nutrition?

Why don’t you get some sleep? Eat better? Don’t drink? Pay attention to your oxygen? Sleep with air? … If you’re over 50 and plan to be here a while, you might sleep on oxygen. I can’t imagine chronic hypoxia would benefit anyone moving here over 50. It may stimulate formation of collateral circulation in the heart, but we’re probably hypoxic enough during the day. It might benefit athletes that want to stimulate those enzymes in their bodies, but even that would be at a moderated level, not at 10,000 ft.

We’re onto something here: Dr. Chris has seen a lot of benefits in some of her patients sleeping on oxygen. If you haven’t already heard, Ebert Family Clinic is currently deep in the middle of a nocturnal pulse oximeter study, where subjects spend one night with a pulse oximeter on their finger to track oxygen levels as they sleep. This will provide more data on whether certain individuals or demographics may benefit from sleeping on oxygen.

In the case of pulmonary hypertension, probably 50% of people who get an electrocardiogram may experience relief from being on air at night. Decreased exercise tolerance when you’re over 50 might be a good case for a recommendation. I don’t think we ever have ‘too much oxygen’ up here; ‘great levels of oxygen at night’ are about 94%. Humans evolved maintaining oxygen day and night [in the 90s], same with sodium, potassium, etc., at a fairly narrow tolerance.

Are there any myths about altitude you find you frequently have to clarify or dispel?

Little cans of oxygen! it’s predatory marketing! It’s so annoying! We’re littering the earth and taking people’s money for ‘air’! Just take some deep breaths, do some yoga for a few minutes … sitting for 30 minutes at an oxygen bar might help. There’s no way to store oxygen in your body, so within 15 minutes, it’s out, but the effects might last, but it gives a false sense of security. 

Also,

IV fluids! DRINK WATER! Or go to a place where you can get real medical care. Most vitamin mixtures, or ‘mineral mojo’, is not real. First of all, don’t get drunk! Drink way less. Dr. Rosen, a geriatric psychiatrist, sees a lot of older guys with MCI (mild cognitive impairment), they’ve had a few concussions, have a drink a day and have lived at altitude for a while. He sees more of these guys here than at low altitude. It’s part of my pitch for guys to sleep on oxygen and minimize alcohol. We don’t have the science to take one or two drinks a week away, but just add oxygen.

Do you have to change the way you prescribe medications due to altitude? Has anything else changed about your practice after moving to altitude?

I don’t [prescribe] steroids as much. Even if it’s rare, I don’t think [steroids] are as benign as other doctors. I avoid antibiotics if possible.

Do you yourself engage in any form of recreation at altitude? How has the altitude played a role in your own experience of this?

I didn’t exercise much until I was 40. [Now] I trail run in the summer, which I think is better than road running (‘cave man’ didn’t have completely flat pavement to run on for miles and miles). In the winter, I skin up the mountain almost every morning; [also] mountain biking. 

Ease in to exercise gradually. Exercise half an hour to an hour a day, but do something every day, even if it’s 10 minutes. And don’t get injured.

Doc PJ also has a handout he most often refers his patients and visitors at High Country Health to, here.

robert-ebert-santos

Roberto Santos is from the remote island of Saipan, in the Commonwealth of the Northern Mariana Islands. He has since lived in Japan and the Hawaiian Islands, and has made Colorado his current home, where he is a web developer, musician, avid outdoorsman and prolific reader. When he is not developing applications and graphics, you can find him performing with the Denver Philharmonic Orchestra, snowboarding Vail or Keystone, soaking in hot springs, or reading non-fiction at a brewery.

Acclimation, Alcohol at Altitude, Altitude Science, Doc Talk, Health, High Altitude, High Altitude Training & Fitness, Medicine, Mountaineering

High Country Healthcare’s Guide to Altitude and Acclimatization

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Welcome to Summit County! At the high elevations of the Colorado Mountains, everyone is affected by altitude to some degree. As you go to higher altitudes, the barometric pressure decreases, the air is thinner and less oxygen is available. The air is also dryer and the ultraviolet rays from the sun are stronger. At elevations of 8,000 plus feet your body responds by breathing faster and more deeply, resulting in shortness of breath, especially on exertion. Many people develop mild symptoms of headache, nausea, trouble sleeping, and unusual tiredness, which we call acute mountain sickness or AMS. These symptoms usually go away in a day or two. If symptoms are severe, persist or worse, you should consult a doctor. A short visit to a physician may save the rest of your vacation.

A more serious condition is called high altitude pulmonary edema or HAPE. This condition is recognized by a wet cough, increasing shortness of breath, and the feeling of fluid building up in your lungs. Other symptoms may include disorientation or confusion. If you feel any of these symptoms developing you need to seek medical attention immediately. HAPE is easy to treat but can be life threatening if left unattended.

The effects of high altitude can be decreased by following these recommendations:

  • Increase Fluid Intake – drink two or three times more fluid than usual, water and juices are best; adequate hydration is the key to preventing altitude illness. You should drink enough fluids to urinate approximately every two hours.
  • Avoid alcohol and minimize caffeine on your day of arrival and one to two days thereafter; be very careful if consuming alcohol, and remember, at this altitude, you may be much more sensitive to the effects of alcohol and sedatives (caffeine and alcohol are dehydrating).
  • Decrease salt intake – salt causes your body to retain fluid (edema), which increases the severity of altitude illness.
  • Eat frequent small meals high in carbohydrates, low in fat, and low in protein.
  • Moderate physical activity and get plenty of rest.
  • Medications and oxygen can help you feel much better. Diamox is a prescription drug which prevents the unpleasant symptoms for many people. Recent experience suggests that a small dose of Diamox suffices: 125 mgs in the morning before you arrive at altitude, again that evening, and each morning and night for two days after arrival. It is generally a well tolerated medicine with few side effects. It should not be taken by anyone who is allergic to the sulfa class of medicines. Some people may experience a tingling sensation in their fingers, toes and around their mouth. You may also notice a subtle change in your sense of taste; especially carbonated beverages may taste flat. As with any medication, take only as directed and discuss any potential side effects with your physician.
  • Studies have shown that spending 1 -2 nights at a modest altitude of 5000 – 6000 feet decreases symptoms when you go higher.
  • The effects of the sun are also much stronger at high altitudes, even in cold weather! Be sure to use sunscreen of at least SPF 15 to avoid sunburn.
  • Have fun and enjoy the mountains!

**This was taken from a handout provided by Dr. C. Louis Perrinjaquet at High Country Healthcare in Summit County, Colorado.**

Acclimation, Altitude Science, Genetics, Health, High Altitude, High Altitude Training & Fitness, Medicine, Sickle Cell

Sickle Cell Anemia at Altitude: a Case Report

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Martin, a 27-year-old African American male, presents to a rural mountain hospital with complaints of left upper quadrant abdominal pain. Martin arrived at altitude (9,400 feet) two days ago from Oklahoma City after a 12-hour drive. Shortly after arriving to his condo in the mountains, Martin developed a dull aching pain to his left upper quadrant. The pain is constant but radiates to his L flank intermittently. Martin tried snowboarding today but had to end his day early because the pain became too severe. Martin cannot identify any aggravating or relieving factors and states that ibuprofen “didn’t even touch the pain.” Martin denies associated nausea, vomiting, diarrhea, constipation, urinary symptoms, fevers, chills, enlarged lymph nodes, or fatigue. His medical history is significant sickle cell trait without active disease. He has a negative surgical history, takes no daily medications, and has no known allergies. *

Differential diagnoses considered include kidney stones, pancreatitis, gastritis, diverticulitis, splenic enlargement, an infarcted spleen, or mononucleosis. Laboratory tests ordered include a complete blood count, reticulocyte count (indicator of immature red blood cells production), lactate dehydrogenase (an indicator of red blood cell destruction), haptoglobin (a binding protein that binds free hemoglobin after red blood cell destruction), a complete metabolic panel, and a urine analysis. A CT scan of the abdomen with contrast was also ordered and performed. 

Martin’s results showed an elevated white blood cell count, sickled cells on his blood smear, mildly elevated reticulocyte count and lactate dehydrogenase, low haptoglobin, and an elevated bilirubin. The remainder of his blood work was unremarkable. The CT scan showed a 40% infarction of his spleen. Martin was treated with oxygen, fluids, and IV pain medication and was promptly transferred to a larger hospital at lower elevation. 

What caused all of this to happen? 

Sickle cell anemia (SCA) is a mutation of the HBB gene that affects the development of normal hemoglobin, the major oxygen transporting protein in the body. SCA is an autosomal recessive genetic disorder which means that two copies of the abnormal gene have to be passed on from both parents in order for the disease to be active in the offspring. So, in other words, if both parents are carriers of the abnormal gene, their offspring have a 25% chance of developing the active disease and a 50% chance of becoming carriers themselves. 

http://www.healthnucleus

The hemoglobin protein is made up of four subunits, 2 alpha-globin and 2 beta-globin. Sickle cell carriers will have a mutation of one of the beta-globin units, resulting in no clinical manifestations of the disease. These individuals live normal lives and are virtually unaffected by the mutation, as seen in Martin’s case. Individuals with active disease will have a mutation in both of the beta-globin subunits, creating sickling of their red blood cells. Sickling of red blood cells makes them less flexible in maneuvering through the vasculature, ultimately resulting in a blockage of blood flow to various tissues in the body. This is cause of severe pain that many individuals experience when in crisis. Sickled cells are also more prone to destruction leading to an anemic state and are inefficient oxygen transporters. 

https://www.flickr.com/photos/nihgov/27669979993

The sickle cell mutation is typically found in certain ethnic groups which is thought to be related to the protective quality of sickled cells from the development of Malaria. The ethnic groups most likely to be affected include African Americans, Sub-Saharan Africans, Latinos, Indians, Individuals from Mediterranean descent, and those from the Caribbean. 

But if Martin was a carrier without active disease, why did he develop sickle cell anemia?

Individuals with the sickle cell trait can cause their cells to sickle under extreme stress including during strenuous exercise, severe dehydration, and when at high altitude. The resulting consequence is the manifestation of all of the symptoms of active disease. Although Martin had never had any symptoms related to his sickle cell trait, he was now in full sickle cell crisis that required immediate intervention. 

What are the implications? 

Individuals from any of the ethnic groups listed above should be tested for the sickle cell trait to ensure they are not carriers. A carrier must exercise extreme caution in ascending to high altitude, should stay well hydrated, and avoid strenuous exercise to prevent the development of a sickle cell crisis. 

*Case scenario is not based on any individual patient rather a compilation of varying presentations seen in the emergency department. 

Liya is 3rd year Doctor of Nursing Practice Student attending North Dakota State University. She lives in Breckenridge, Colorado and works as a registered nurse in the Emergency department. Liya was born in Latvia and moved to the United States in 1991 with her family. She grew up in the Washington, DC area until she moved to Colorado in 2012.  She is passionate about helping immigrant families and other underserved individuals gain access to basic healthcare services. She hopes to work in Family Medicine in a federally qualified health center in the Denver metro or surrounding areas. In her spare time, Liya enjoys hiking, snowboarding, biking, and camping. 

References

Adewoyin A. S. (2015). Management of sickle cell disease: A review for physician education in Nigeria (sub-Saharan Africa). Anemia, 2015. doi:10.1155/2015/791498

American Society of Hematology. (n.d). Sickle cell trait. Retrieved from https://www.hematology.org/Patients/Anemia/Sickle-Cell-Trait.aspx

Mayo Clinic. (2018). Sickle cell anemia. Retrieved from https://www.mayoclinic.org/diseases-conditions/sickle-cellanemia/symptoms causes/syc-20355876

U.S National Library of Medicine. (2019). Sickle cell disease. Retrieved from https://ghr.nlm.nih.gov/condition/sickle-celldisease#inheritance

Yale, S.H,, Nagib, N., & Guthrie, T. (2000). Approach to the vasoocclusive crisis in adults with sickle cell disease. American Family Physicians, 61(5), 1349-1356. Retrieved from https://www.aafp.org/afp/2000/0301/p1349.html

Acclimation, Alcohol at Altitude, Altitude Science, Child Growth & Development, Health, High Altitude, High Altitude Training & Fitness, Medicine, Mountaineering, Technology

The Legacy of the Mountain Guru: Prof. Dr. Gustavo Zubieta-Castillo

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We’ve published a series of accounts from Dr. Chris’s recent attendance at the 7th Annual Chronic Hypoxia conference in La Paz, Bolivia , conducted by Dr. Gustavo Zubieta-Castillo. He is one of the world’s leading experts of altitude medicine and Dr. Chris’s collaboration and contact with him has added literally phenomenal insight into our own high altitude research.

Dr. Chris “en Teleférico” with fellow altitude researchers Vanessa Moncada, Diana Alcantara Zapata, Dzhunusova G. S., Oscar Murillo, and Alex Murillo. Photo courtesty of Dr. Zubieta-Castillo.

There is something literarily romantic about the scientists who are compelled to remind you, “I’m not crazy!” Dr. Zubieta-Castillo has held soccer games at 6,542 m (21,463′), proving the remarkable adaptability of the human body. He maintains a high altitude training lab, called the Chacaltaya Pyramid, at 5,250 m (17,224′). In his recent video (below), he illustrates the connection between longevity and elevation, where citizens of the highest cities in South America live to be well over 100.

It’s notable that a city known for its wine at 2,790 m (9,153′), called Chuquisaca, boasts some of the oldest residents. Not surprisingly, our research has led us to some speculation on the relationship between alcohol and the body at altitude. Additionally affirming is Dr. Zubieta-Castillo’s father, nicknamed “El Guru de la Montaña”, who began his legacy of altitude research and medicine by examining the hearts of dogs at altitude (sound familiar? See our article on Dogs at Altitude), as well as Dr. Zubieta-Castillo’s own testament that asthma can be and has been treated by altitude (see Asthma at Altitude).

His latest correspondence with Dr. Chris and their mutual colleagues reads like letters written by history’s greatest scientists, beginning,

Dear Colleague Scientists:

The 7th Chronic Hypoxia Symposium, thanks to your outstanding participation was a great success !! We shared great scientific, friendship and enthusiasm from 16 countries, along with travel and conferences in fascinating environments, all at high altitude.

The letter ends with an invitation to all colleagues to contribute their own research to the first chronic hypoxia-dedicated issue in a top medical journal, so be on the lookout for Dr. Chris’s contribution (which we will be sure to share here).

The video below is a fascinating look into some of Dr. Zubieta-Castillo’s latest research, including his theories and recommendations on conditioning humans in space with hypoxia, a dissertation that was initially dismissed as irrelevant, then subsequently published. Enjoy!

robert-ebert-santos

Roberto Santos is from the remote island of Saipan, in the Commonwealth of the Northern Mariana Islands. He has since lived in Japan and the Hawaiian Islands, and has made Colorado his current home, where he is a web developer, musician, avid outdoorsman and prolific reader. When he is not developing applications and graphics, you can find him performing with the Denver Philharmonic Orchestra, snowboarding Vail or Keystone, soaking in hot springs, or reading non-fiction at a brewery.