Category Archives: High Altitude

High Altitude Training for Better Sea Level Performance

High altitude training has become very popular among endurance athletes over the past few years. This trend has developed due to emerging evidence that chronic exposure to altitude improves overall performance at sea level. There have been multiple peer reviewed studies proving that physiologic changes which occur with high altitude training are beneficial for low altitude performance. The physiological changes that occur in response to decreased oxygen availability include increased erythropoietin response, leading to an increase in red blood cell production. These physiological changes lead to an improvement in oxygen carrying capacity and the delivery of oxygen to muscles. The ability to store iron is also increased. Even though these physiological responses appear to have beneficial effects, they can also be detrimental. Some studies have indicated a “detraining effect” associated with long term high altitude training. The low oxygen available at high altitude impairs the ability to train at high intensity, which can in turn negate the improvement in VO2 max.

Given the most recent data collection, the mantra of “Live High, Train Low” has been adapted. The idea behind this thought process is that the athlete is able to gain all of the beneficial physiological changes of training at high altitude, while still being able to train at high intensities at a lower elevation. In order to gain the highest advantage from high altitude training, a series of clinical guidelines has been published. The guidelines state that the optimal altitude at which to live and train is between 2000-2500m. Although altitudes about 2500m provide the beneficial physiologic effects previously stated, they are also associated with negative effects such as decrease in quality of sleep. The guidelines also recommend all training performed at altitude to be of low intensity, and to reserve high intensity workouts for lower altitudes. Furthermore, it is recommended that in order to maximize the benefits of altitude training, one should remain at altitude for a minimum of 21 days. Finally, it is recommended to compete either within 48-72 hours after returning to sea level or to wait approximately 14 days before competing.

Altitude training is nothing new to the elite athlete. This has been a tool used by many top athletes over the years in order to gain as much advantage as they can on the day of a competition. It is these specific guidelines which have been recently been published that give more precise strategies to optimize sea level performance. It is, however, always important to keep in mind that although the above guidelines can give both professional endurance and everyday athletes the best chance of improving their competitive performances, the response to high altitude training can vary from one individual to another.

Anna Miller, PA-S

Carly Stillman, PA-S

Red Rocks Community College Physician Assistant Program

Resources:

Constantini, K., Wilhite, D. P., & Chapman, R. F. (2017). A Clinician Guide to Altitude Training for Optimal Endurance Exercise Performance at Sea Level. High Altitude Medicine & Biology. 18(2), 93-101.

Can I take my child up a 14er?

There are over fifty 14ers in Colorado. A 14er is a mountain with an elevation of at least 14,000 feet. If summited, these majestic peaks afford their climbers spectacular views of the surrounding landscape. Being that many people within Colorado – and those who come to visit – are active, a question often voiced by parents is: “Can my child hike up a 14er with me?” Unfortunately, there is no straightforward answer to this question and the simplest response is: it depends.

According to recent research, it appears that children are largely similar to adults when it comes to adapting to higher elevations. Research examined children’s short-term cardiorespiratory adaptation, incidence of acute mountain sickness, hypoxic ventilatory response, and maximal exercise capacity and found little variance between adults and children (Garlick, O’Connor, & Shubkin, 2017).

When CAN you take your child up a 14er? There are a multitude of factors that affect when and if a child can climb a 14er. For example, children develop and mature at different rates. This might affect whether your 11-year-old is able to climb a 14er, compared to someone else’s 11-year-old. Additionally, some children grow up being exposed to technical hikes and climbs, while others are not. This affects ability level and is certainly something to keep in mind (Provance, n.d.). Another factor to keep in mind is whether you’re child has an underlying condition. For example, conditions such as congenital heart disease, asthma, sickle cell anemia, an upper respiratory infection, or an ear infection can significantly increase the risk for high altitude illnesses (Garlick, O’Connor, & Shubkin, 2017, p. 6). Yet another factor is whether you live at altitude or are visiting from a lower elevation. There is a strong recommendation for those individuals traveling from a lower altitude to take some time to acclimate. Spending a night or two at an intermediate altitude is recommended. Additionally, be mindful not to overdo it when you do ascend to a higher elevation: stay hydrated and don’t overexert yourself. If you decide to climb a 14er, it is imperative that you give your body at least a few days to acclimate to the altitude (“How can I optimize my health at high altitude?”, 2016).

So, what’s the bottom line? Since it isn’t possible to place a concrete age on when it’s okay for your child to climb a 14er, it is ultimately up to you to know you’re child’s limits and to decide if such a challenging hike is right for you and them. The most important thing is to make sure that everyone remains safe.

If you do decide to set out on the challenge of hiking up a 14er, there are some things to remember in order to keep yourself and your child as safe as possible and ensure that the hike is an enjoyable experience for all (Kirkland, 2015):

  • Set out early: Summiting the peak by noon is recommended in order to avoid afternoon weather, thunderstorms, and potential lightning strikes.
  • Start slow and easy: It’s important for you to determine whether or not you’re child will be able to summit a 14er. Start with easy hikes and build up over time so that you have a good understanding of your child’s abilities.
  • Know the weather forecast: Check the weather before you set out to prevent getting stuck in a storm.
  • Clothing: Wear appropriate clothing. It is important to layer since it can be colder on top of the mountain. Additionally, it is important to wear clothing that protects you from the elements (including the sun!).
  • Protect yourself from the sun: The sun can be very strong when one is high up. It is very important to ensure that your child is adequately protected from the sun: sunscreen, clothing, etc.
  • Food and Fluids: Bring adequate nutrition and hydration.
  • Be prepared to turn around ahead of time: There are many things that could cause you to turn around. It’s very important to accept ahead of time that you might not manage to summit the peak and to accept that’s okay.
  • High altitude illness: It is incredibly important for you to know the symptoms of high altitude illness and be prepared to turn around should your child exhibit any of them. Symptoms of high altitude illness include: fussiness or irritability, refusal to eat, lack of energy, nausea and/or vomiting, dizziness, and light headedness (Provance, n.d.).

References:

Garlick, V., O’Connor, A., & Shubkin, C. D. (2017). High-altitude illness in the pediatric population: A review of the literature on prevention and treatment. Current Opinion in Pediatrics, doi:10.1097/MOP.0000000000000519

How can I optimize my health at high altitude? (2016). Retrieved from http://www.altitudemedicine.org/optimizing-health-at-altitude/

Kirkland, E. (2015, May). Taking kids to new heights: Hiking Colorado’s “14er” mountains. Retrieved from http://www.outdoorfamiliesonline.com/hiking-colorados-14er-mountains/

Provance, A.J. (n.d.). What age can my child start hiking fourteeners? Retrieved from https://www.childrenscolorado.org/conditions-and-advice/new-and-featured-articles/sports-safety/when-can-kids-start-hiking-fourteeners/

Rianne Smeele, BSN, RN, Regis University FNP Student

Is There a Need for At Home Infant Monitors?

People living at higher altitude, such as here in Summit County, where the elevation is above 9,000 feet, commonly have lower oxygen saturations than people residing at lower elevations. It has been suggested, but not proven, that hypoxia (low oxygen saturation) may be a contributing factor to SIDS. Does this mean parents at high elevations should constantly monitor their healthy babies at night? The simple answer? No.

A study from 2015 states that “residence at high altitude was significantly associated with an increased adjusted risk for SIDS.”1 However, one of the authors from that study, Dr. David Katz, a cardiologist at the University of Colorado Denver, states that “the absolute risk of SIDS remains very low, and … this is in no way a call to abandon residence in or visits to high-altitude” locations. The authors stress ’that even at high elevations, the risk of SIDS is still low. Even above 8,000 feet, a baby’s chance of dying of SIDS is only 0.079 percent.” 5

The Owlet is a new infant physiologic monitor built into a sock that monitors heart rate and oxygen saturation. It connects to smartphones and is advertised to alert parents when something is wrong with their baby. However, their website clearly states the $250 device is “not a medical device,” and is only intended to provide a “peace of mind” for parents. It is “not intended to diagnose, treat, mitigate, cure, or prevent any disease or condition.”4 Healthy infants sometimes have desaturations less than 80% without consequence, and these monitors could lead to over-diagnosis and instill unnecessary fear into parents of healthy babies.2 An American Academy of Pediatrics policy states “home cardiorespiratory monitoring should not be prescribed to prevent SIDS.” Multiple studies have been unable to provide a need for their use on healthy babies.3

We bought an Owlet to try for our clinic, and were not impressed. One employee had a difficult time getting it to stay on her newborn; whereas another employee said it didn’t hold a charge very well, and the alarm would sometimes go off without reason.

Healthy babies are healthy babies! There are proven practices that decrease the risk of SIDS—supine sleep position, safe sleeping environments, and elimination of prenatal and postnatal exposure to tobacco smoke.3 Currently, there is no proven need to purchase and use infant physiologic monitors, such as the Owlet, on your healthy babies!

 

Kayleigh Belsey, PAS-II

Midwestern University Physician Assistant Program

Clinical Rotation- June 2017

References

  1. Katz, D., MD, Shore, S., MD, Bandle, B., MPH, Niermeyer, S., MD, MPH, Bol, K. A., MSPH, & Khanna, A., MD. (2015). Sudden Infant Death Syndrome and Residential Altitude. Pediatrics, 135(6). Retrieved June 25, 2017, from http://pediatrics.aappublications.org/content/pediatrics/early/2015/05/20/peds.2014-2697.full.pdf
  1. Bonafide, C. P., MD, MSCE, Jamison, D. T., MBA, BSEE, PMP, & Foglia, E. E., MD, MSCE. (2017). The Emerging Market of Smartphone-Integrated Infant Physiologic Monitors. Journal of the American Medical Association, 317(4), 353-354.
  1. Apnea, Sudden Infant Death Syndrome, and Home Monitoring. (2003). Pediatrics, 111(4), 914-917. Retrieved June 25, 2017, from http://pediatrics.aappublications.org/content/pediatrics/111/4/914.full.pdf
  1. Http://www.owletcare.com/. (n.d.). Retrieved June 25, 2017.
  1. Pappas, S. (2015, May 25). Sudden Infant Deaths Linked to Elevation. Retrieved June 25, 2017, from https://www.livescience.com/50956-sudden-infant-deaths-elevation.html 

Slumber Up: Sleeping at High Altitude

 

Does high altitude affect sleep quality? The answer is that for some, it does. If you’ve ever quickly arrived to the mountains on a ski or summer getaway, you may have experienced fitful and non-restful sleep. Individual responses to high altitude may vary, however there is an understood physiological basis for sleep disruption at altitude.

 

A phenomenon known as “periodic breathing of altitude” is commonly experienced above 2500 m of elevation (about 8200 ft) in those not previously acclimatized [2]. This is a common sleep elevation in Colorado mountain towns such as Frisco, Colorado (proud home to this blog!). Periodic breathing of altitude may be more likely to occur as sleeping altitude increases. Here’s the science behind it:

 

The decreased atmospheric pressure at altitude results in less oxygen driven into the lungs and through to the bloodstream. The body attempts to compensate by increasing the rate of breathing (tachypnea), which also causes more carbon dioxide to be exhaled. Chemoreceptors sense the decrease in carbon dioxide and signal the body to stop breathing temporarily (apnea) to correct the imbalance. Alternating cycles of tachypnea and apnea continue to occur during sleep. The result is decreased REM sleep, which is a critical restful and rejuvenating phase [2].

 

Worried about your next sleepless night on a mountain trip? Fortunately, there’s acetazolamide (Diamox). It is a carbonic anhydrase inhibitor that works by eliminating bicarbonate in the urine, which is a base. The body subsequently becomes more acidic, and that acid in the bloodstream is readily converted to carbon dioxide. The body is “tricked” into thinking that there is plenty of carbon dioxide present in the bloodstream, and periods of apnea during sleep may be reduced or eliminated [3].

 

To help prevent periodic breathing of altitude, adults can take acetazolamide preferably starting on the day before ascent or on the first day at altitude. Adults typically take 125 mg twice a day until either 3 days at altitude has been reached or descent back down has occurred [1]. Ask your healthcare provider about what’s right for you. Consider acetazolamide next time you’re sleeping up high, and get that refreshing sleep that allows you to better enjoy the things you love at altitude!

 

-Justin Murphy, PA-S

Red Rocks Community College Physician Assistant Program

Clinical Rotation- May 2017

 

References

1) Athena Health (2017). Acetazolamide generic. Epocrates Online. Retrieved from: https://online.epocrates.com/drugs/12701/acetazolamide/Adult-Dosing

2) Gallagher, S. A., Hackett, P., & Rosen, J. M. (2017). High altitude illness: Physiology, risk factors and general prevention. Up To Date, Topic 181,  Version 20.0.  Retrieved from: https://www.uptodate.com/contents/high-altitude-illness-physiology-risk-factors-and-general-prevention?source=search_result&search=high%20altitude%20sleep&selectedTitle=2~150

3) Winter, C. (2016). Sleeping around: How to sleep at high altitude. Huffington Post. Retrieved from: http://www.huffingtonpost.com/entry/sleeping-around-how-to-sleep-at-high-altitude_us_5806da29e4b08ddf9ece1228?ncid=engmodushpmg00000006

Heart Attack Deaths at Elevation in Visitors

Last year in Summit County, 23 people died of heart complications, 19 of which were visitors ascending to higher altitude.  Most of these visitors were in their 50s or older and died within one to two days after coming to elevation (Queen, 2017).

Acute exposure to high altitude over 2500 m can cause great strain on the body and is associated with significant alterations to the cardiovascular system such as tissue hypoxia and increased pulmonary artery pressures.  Although the concentration of oxygen at elevation is the same at sea level, the air is thinner causing less oxygen to breath.  At sea level the percent of effective oxygen concentration is around 20% where as in Summit County the percentage of effective oxygen drops down to 14%.  At higher elevation such as the ski areas the percentage of effective oxygen drops down to 13% (Queen, 2017).  As a result, the heart will pump faster to increase the delivery of oxygen to the body.  The cardiac stress at rest is minimal, however it can be significant during exercise.  Anyone with some degree of heart complication can worsen the stress on their heart when coming to higher elevation (Bach, 2013).

Hypoxemia due to high altitude can cause poor oxygenation of the lungs and constriction of blood vessels, causing an increase in pulmonary pressure and increasing hypertension.  Therefore, an acute exposure to high altitude can cause cardiovascular stress.  Residents of high elevation tend to do better because they have anatomical and physiological changes in their cardiovascular system that allows them to adapt to high-altitude chronic hypoxia (Hurtado et al., 2012).

It is recommended that any patients with cardiovascular disease who are from sea level and planning to come to elevation should slowly acclimatized themselves by staying in Denver for a day or two prior to going above 2500 m.  Patients who have stable heart complications should limit their physical activity for the first few days after ascending to elevation.

Hong Nguyen, PA-S

Physician Assistant Student

Red Rocks Community College

References:

Reference:

Bach, D. (n.d.). Altitude and the Heart: Is Going High Safe for Your Cardiac Patient? Retrieved March 28, 2017, from http://www.expeditionmedicine.co.uk/index.php/advice/resource/r-0034.html

Hurtado, A., Escudero, E., Pando, J., Sharma, S., & Johnson, R. J. (2012). Cardiovascular and renal effects of chronic exposure to high altitude. Nephrology Dialysis Transplantation, 27(Suppl 4), Iv11-Iv16. doi:10.1093/ndt/gfs427

J. Q. (n.d.). High elevation may be linked to visitor heart attach deaths. Summit Daily, pp. 1-4.

Concussions and Altitude

With the number of concussions on the rise it is important to have an understanding of the occurrence of concussions as well as the management of concussions at higher elevations. Although the incidence of concussions is on the rise everywhere, high school athletes playing at higher elevations may actually be less likely to sustain a concussion when compared to athletes playing the same sports at sea level.

The Cincinnati Children’s Hospital conducted a research study examining the relationship between concussions and altitude among NFL athletes. The results of the study demonstrated a 30% decrease in the incidence of concussions in athletes playing at higher elevations (greater than or equal to 644 ft above sea level) (Myer et al., 2014). While there is no definitive explanation for this it is believed to be linked to the physiological changes of the brain at altitude. Concussions are typically caused from the rapid acceleration/ deceleration of the brain inside the skull. The hypothesis is that at higher elevations the brain tends to swell due to a mild increase in intracranial volume creating a tighter fit of the brain in the skull, leading to less damage caused by sheer forces (Myer et al., 4014).

While concussions may not be as common at elevation they are still occurring more than ever with detrimental long term effects if not recognized and treated properly. One thing we can do to recognize and treat concussions is to complete an ImPACT test. ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing) is a computerized neurocognitive test which helps to assess neurologic changes after a concussion and helps guide recovery (Glendenning, 2017). The idea behind ImPACT is for individuals to have a baseline test, prior to any head injury/ concussion, and if a traumatic brain injury occurs, that individual would then undergo a post-concussion test, comparing the results to their baseline.  This helps better determine when it is safe for that individual to return to play without sustaining further injuries to their brain.

With the active lifestyle of children and adults in living at high altitudes, ImPACT testing may be just another step to consider when getting your bike tuned up for bike season, or your skis ready for a weekend on the slopes. Even if you aren’t a competitive athlete on a designated team, anyone at risk of hitting their head is at risk of suffering a concussion and would benefit from completing a baseline ImPACT test. ImPACT testing is available for only $15 at Avalanche Physical Therapy and takes only 30 minutes to complete (Glendenning, 2017). By being pro-active now you can help ensure a safer and healthier recovery in the future.

Schedule your baseline ImPACT testing at Avalanche Physical Therapy today!

www.avalanchetherapy.com

Betsy Metz, PA-S

Physician Assistant Student

Red Rocks Community College

References

Glendenning, L. (2017, March 7). Cognitive testing tool used to assess traumatic brain injuries in Summit County. Summit Daily News, p. 5.

Myer, G. D., Smith, D., Barber Foss, K. D., Dicesare, C. A., Kiefer, A. W., Kushner, A. M., … & Khoury, J. C. (2014). Rates of concussion are lower in National Football League games played at higher altitudes. journal of orthopaedic & sports physical therapy, 44(3), 164-172.

Does Hypoxia Prevent Cancer?

Summit Daily News recently published an article based on research in the Journal of the American Medical Association showing Summit County                                                                                                       with the lowest cancer rate in the nation FOR 30 YEARS. Are people moving away when they get cancer? No, they are treated in Vail, Denver                                                                                                      and now the St. Anthony Summit Medical Center.  Do we have fewer older people? No, there is a large percentage of retired residents.

The report shows stark differences in regional cancer death rates : detailed estimates for deaths from nearly 30 types of cancer in all 3,100 U.S. counties for over 35 years.From 1980 to 2014, the U.S. death rate per 100,000 people for all cancers combined dropped from about 240 to 192 — a 20 percent decline. More than 19 million Americans died from cancer during that time, the study found. Healthy lifestyle with low rates of obesity and smoking and increased physical activity contribute to low cancer rates in the mountains.

The picture was rosiest the Colorado ski country, where cancer deaths per 100,000 residents dropped by almost half, from 130 in 1980 to just 70 in 2014;

drugs and altitude:

Consensus by International Federation on Drug Use at High Altitude

New Rochelle, NY, October 25, 2016—Drug taking at high altitude is variably intended to enhance performance, prevent or alleviate the debilitating effects of altitude, or for pleasurable use. In some cases, certain drugs can be advantageous and even life-saving, but many drugs lack evidence of benefit and carry risks of side effects or interactions. The International Climbing and Mountaineering Federation (UIAA) has published evidence-based guidelines advising on the safe use of alcohol, steroids, oxygen, erythropoietin, and many other types of drugs in mountain environments in an article in High Altitude Medicine & Biology, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. The article is available free online on the High Altitude Medicine & Biology website.

An international team of researchers from Kuwait, Austria, United Kingdom, Germany, Switzerland, Nepal, Spain, France, and the Netherlands, led by David Hillebrandt, MB, BS, President, UIAA Medical Commission, coauthored the article entitled “Drug Use and Misuse in the Mountains: An UIAA MedCom-Consensus Guide for Medical Professionals.” They conducted an extensive review of the medical literature, trials, observational studies, and case series to assess the evidence available for drugs commonly used by mountain climbers. Their conclusions and recommendations cover a broad range of drug types including alcohol, anabolic agents such as androgenic steroids, adrenergic agonists, beta-blocking agents, erythropoietin, oxygen, glucocorticosteroids, benzodiazepines, and stimulants such as amphetamines.

“The use of drugs beyond those proven effective in preventing and treating high altitude illnesses remains very controversial among both physicians and climbers,” says Erik R. Swenson, MD, Editor-in-Chief of High Altitude Medicine & Biology and Professor, Division of Pulmonary and Critical Care Medicine, Veterans Administration Puget Sound Healthcare System. “This broad and comprehensive review of the myriad drugs used for various purposes in climbing will be useful to all concerned in decision-making about their use, determining the level of supportive evidence, and importantly their potential costs and adverse effects.”

Red Cheeks in Mountain Kids

img_2010Chinese doctors presenting at the 7th World congress of Mountain and Wilderness Medicine in Telluride last month showed us a familiar photo. They called it Plateau Facial Persistence Erythema and we commonly see it here in Summit County. This rash occurs in women and children under conditions present at the plateau region at high altitude with cold and windy winter temperatures. It’s characteristics are erythemacheeksor redness, of the cheek prominences that is darkest in the center and can even look purple in color. The redness can spread in a spider-like pattern from the center with a gradual transition to normal-appearing skin. It is painless and often symmetrical. The cause of this rash is unclear but is thought to be related to changes at high altitudes affecting vasomotor nerve function, decreased capillary elasticity with persistent expansion, and increased blood viscosity secondary to increased hemoglobin. Children have delicate skin that may not adapt as easily to this extreme environment, causing the rash. Treatment primarily involves prevention by avoiding cold temperatures, windy areas, and UV radiation. In other countries these rosy red cheeks are not considered a disease, but rather a beautiful variant of normal!

High-Altitude Lung Edema Can Mimic Pneumonia in Kids, Even Without Travel by Rob Goodier

Dr. Chris has the medical community talking about HAPE!!!

“Health providers should advise patients who live at or travel to high altitude to have a pulse oximeter and check their oxygen levels if they are unwell,” the study’s author, Dr. Christine Ebert-Santos at the Ebert Family Clinic in Frisco, Colorado, told Reuters Health…

Click the link to read more:

High-Altitude Lung Edema Can Mimic Pneumonia in Kids, Even Without Travel by Rob Goodier

http://www.medscape.com/viewarticle/867210