Altitude and the AthleteMark E. Lavallee, MD, CSCS, FACSM

Director, WellSpan York Sports Medicine Fellowship

Head Team Physician, Gettysburg College

Chairman, USA Weightlifting Sports Medicine Society

Medical Director, IWF Masters World Championships

Feb 1st 2017

Conflicts of Interests

• I have no conflicts of interest in regards of this topic.

• I have no financial relationships to divulge that would impact the bias nature of this lecture other than:• Himilayan Tourist Board Grant Recipient

• GAMOV altitude bag- sales representative

• Paid Spokesmodel for the SHERPA’S UNION of CENTRAL KATMANDU (S.U.C.K.)

• Patients mentioned in this lecture have given permission to use their likeness for educational purposes

Altitude Experience

• Former free-climber who was injured

• Highest altitude • Hiking: Pikes Peak: 14,132 ft

• Mountain Biking: Rocky Mountain Natl Park 12,500 ft

• Sight-seeing Mt. McKinley or Mt. Denali 23,405 ft

Objectives

• High Altitude:• Travel : indications/contraindictations• Definition/ Pathophysiology

• Major Altitude Conditions: • AMS, HAPE, HACE

• Minor Altitude Conditions: • HA Bronchitis, HA Retinopathy, UV Keratitis

• Associated Conditions: • Trauma, Pregnancy, CAD, vascular conditions

• Altitude Training – “Live High, Train Low”

The Climb by Anatoli Boukreev

• “As climber’s fought for survival, they were often blind but for an arm’s length. Sometimes there were ropes to secure and guide them. The pressure gauges on their oxygen tanks fell to zero, and the raging hypoxia began to conquer the most rational figurings. the foretelling numbness of frostbite pushed the possibilties of amputation…” 1997

Introduction

• High Altitude :• altitude > 1500m or 4,921 ft

• More people are trekking to the Himalayas, climbing the Rockies, & skiing the Alps.

• About 94 million people traverse terrain above 2,285m or 7,500 ft since 1984.

• > 25% of those who travel to 8,500ft (2590m) develop high-altitude illness

Contraindictations for High-Altitude Travel

• Uncompensated Congestive Heart Failure

• Pulmonary Hypertension

• Sickle Cell Anemia

• Severe Chronic Obstructive Pulmonary Disease

Cautions for High-Altitude Travel

• Compensated Congestive Heart Failure

• Troublesome arrhythmias

• Sickle cell trait

• Moderate COPD

• Seizure disorder (not controlled on meds)

• Stable angina or CAD

• Sleep apnea

• High-risk pregnancy

Wilderness Athletes, Climbers, and Adventure Racers: Pre-Part Exam• It is recommended to perform a pre-participation exam due to:

• isolation of sport

• difficulty in access emergent medical care

• Increased intensity of workload

• Increased of trauma injuries

Campbell et al, Wilderness Environ Med. 2015 Dec;26(4 Suppl):S30-9.

High-Altitude Illnesses

• Acute Mountain Sickness (AMS)

• High-Altitude Pulmonary Edema (HAPE)

• High-Altitude Cerebral Edema (HACE)

• High-Altitude Retinopathy

• Peripheral Edema

• Venous Stasis & Thrombotic Complications

• High-Altitude Pharyngitis & Bronchitis

• Ultraviolet Keratitis (Snow Blindness)

• Dehydration/Heat Exhaustion

• Injuries

Pathophysiology

• Hypoxia is main contributor to high-altitude illness.

• Barometric pressure & partial pressure of oxygen decrease• w/ elevation and as one moves NORTHWARD.

• At sea level, Barometric pressure is 760 mmHg.

• Temperature drops 6.5oC for every 1000m.

Elevation & Latitude

• Mt. Everst (29,028ft/8,850m) has barometric pressure of 253 mmHgat 27o latitude.

• If Mt. Everst were at 62o latitude, like Mt. McKinley (20,320ft/6,200m), pressure would be 222 mmHg.

Changes as one climbs

Elevation Atmos.

Pressure

PaO2

(adult)

Temp.

Sea level 760mmHg 95 mmHg 23oC

9,200 ft

(2,800m)

543mmHg 60 mmHg 6oC

20,140 ft

(6,100m)

356mmHg 35 mmHg -16oC

29,000 ft

(8,800m)

253mmHg 31 mmHg -34oC

Ultraviolet Light

• Penetration increases by 4% per 300m gain in elevation.

• Risks:• UV Keratitis (snow-blindness)

• Sun-burn

• Skin Cancer (long-term exposure)

• UV light can reflect off snow/ice and produce temperatures of 40oC/104oF.

• Heat Exhaustion (esp. in tent)

Dehydration

• Insensible loss

• Increased work

• At high altitude, only way to get water is to melt ice

• Heat Exhaustion

Pathophysiology

• As one ascends, chemoreceptors in carotid body:• detect decrease PaO2

• stimulate hyperventilatory response

• hyperventilation

• incr. water loss

• incr. PaO2

• decr. in PaCO2

• Cheyne-Stokes Breathing (usually nocturnal)• causes a respiratory alkalosis, pH is stabilized w/in 24 hrs by bicarb excretion from kidneys.

RF Chapman, “The Individual Response to training at Altitude,” Br J Sports Med. 2013 Dec;47 Suppl 1:

Pathophysiology

• Catecolamine incr. b/c low PaO2 and low blood volume 2o to dehydration.

• incr. HR

• incr. BP

• incr. venous tone

• The tachycardic response is used to see how well acclimatized a climber is.

• First morning at elevation, HR should be 20% higher, goes down over a week.

Pathophysiology

• Hypoxia increases contractility of pulmonary vessels.• incr. pulmonary artery pressure• incr. cerebral blood flow

• To improve blood’s O2 carrying capacity• incr. erythropoietin (w/in 2 hrs)• more RBCs (w/in 4 days)• incr. 2,3-DPG production shifts O2-Hgb dissociation curve to right.• incr. capillary density in skeletal muscle.

• J. Dempsey, et al, J Appl Physiol (1985). 2014 Apr 1;116(7):858-66

Pathophysiology

• Acute adaptations occur can quickly!!

• Example:• 5 out of 10 people from 1947 to1993

who stowed away w/o survival gear in the wheel wells of airliners that flew at 11,900m (39,000 ft) on transcontinental flights survived!!

Pensacola Navy Flight SchoolSimulation at 30,000ft loss of pressurized cabin

Click HERE for video

Acute Mountain Illness

• First Description:• Kan, Chinese government official,at 37 B.C.:

• “A man’s face turns pale, his head aches and he begins to vomit” when crossing the Himalayan Kilak Pass.

Acute Mountain Illness

• AMS affects • 15-30% of Colorado Resort Skiers

• 50% of climbers on Mt. McKinley

• 70% of climbers on Mt. Rainier

• 25-50% of climbers to Mt. Everst base camp

Acute Mountain Illness

• Symptoms:• Headaches

• Fatigue

• Gastrointestinal upset (N/V/Anorexia)

• Difficulty sleeping

• Light-headedness

Acute Mountain Illness

• International Hypoxia Symposium (Lake Louise, Alberta, Canada, 1993):

• AMS is HA plus one other symptom in light of recent gain in altitude.

Lake Loiuse Score: AMS• 1) Headache 0-3pts

• 2) GI Sxs 0-3pts

• 3) Fatigue/weakness 0-3pts

• 4) Dizzy/LH 0-3pts

• 5)Difficulty Sleeping 0-3pts

TOTAL 15pts

Additional Scoring

6) Change in mental Status 0-3pts

7) Ataxia 0-3pts

8) Peripheral Edema 0-3pts

9) Functional Scoring 0-3pts

Acute Mountain Illness

• Headache• probably caused by mild increase in

intracranial pressure.

• typically, throbbing, bitemporal, or occipital

• worse at night or early morning

• worse w/ valsalva or bending forward

Acute Mountain Illness

• Dyspnea• Dyspnea on exertion is common at elevatio

• Dyspnea at rest indicates severe AMS or HAPE

• Symptoms that may mimic include:• viral illness

• Carbon Monoxide Poisoning (cooking stoves used in tents)

• exhaustion

• dehydration

Acute Mountain IllnessTreatment:

• Stopping ascent & allowing acclimatization.• Acetazolamide (Diamox), a CAI & diuretic, 250 mg PO BID.

• 125mg PO BID for prophalaxis• Showed in 155 trekkers in Nepal decr. Incidence of AMS ovr placebo (Basynat et al; High Alt

Med Bio 2003)

• Dexamethasone 4mg q 6 hours• 4mg q 6-12hours for prophalaxis• Less effective than Diamox for preventing AMS (Ried et al.; J Wilderness Med, 1994)

• Ginko Extract: no preventative effects for AMS.• Alternatively, descend 460m/1500 ft or more until sxs resolve.• ASA useful in treating HA.

• Non-barbiturate sedative can improve sleep.

Acute Mountain Illness

• Post-AMS recommendations:• GRADUAL Ascent can resume once sxs resolves.

• No evidence to support counseling patient to avoid altitudes after episode of AMS.

• Reoccurence rate not increased with repeated ascents.

High-Altitude Pulmonary Edema

• HAPE: A form of non-cardiogenic pulmonary edema and is associated w/ marked pulmonary HTN

• 15% of travelers to altitudes > 2,500,/8,200ft will develop HAPE depending on:

• age (<20y.o.)

• sex (M>F)

• rate of ascent

High-Altitude Pulmonary Edema

• Diagnostic Criteria : 1991 Hypoxia sympos.• In setting of recent gain in altitude, at least two of the following symptoms

must be present:

• Dyspnea at rest

• Cough

• Weakness

• Decreased exercise performance

• Chest tightness or congestion

High-Altitude Pulmonary Edema

• Diagnostic Criteria (continued)• At least two of the following signs must be present:

• Rales or wheezing in at least one lung field (RML)

• Central Cyanosis

• Tachycardia

• Tachypnea

High-Altitude Pulmonary Edema

• Occurs 1 to 3 days after ascent is begun

• It is a medical emergency!!

• The most common cause of death at high altitude.

Example of HAPE:Tom Whittaker on Mt. Everst

Click HERE to see Video

Look at 2 minutes

High-Altitude Pulmonary Edema

Treatment:

• Immediate descent of 610m/2000ft until sxs resolved is the Definitive Treatment!!

• If HAPE severe enough that pt. cannot descend• Rest & Keep warm• Give Oxygen at 4-6 LPM• Nifedipine SR 20mg PO q 8-12 hours• Serevent Salmetrol) 125mcg q 12 hours• Viagra (Sildenafil) 20mg q 6-8 hours• Cialis (Tadalafil) 10mg every 12 hours

Fiore, Hall, et al; “Altitude Illness; Risk Factors, Prevention and Treatment,” Am Fam Phys Vol 82(9) p1103-1110 (11/1/2010

High-Altitude Pulmonary Edema

• Treatment:• Portable single person hyperbaric

bags • Gamow

• Chamberlite

• Mulit-person hyperbaric bags

High-Altitude Pulmonary Edema

• Treatment using a CPAP helmet• 2, 30 minutes trmts

• Setting: 15cm2 H2O

• With meds• Diamox/dexameth/nifed

FIGURE 2. This photo shows a 52-year-old mountaineer suffering

from high-altitude pulmonary edema (HAPE) whois treated with a

continuous positive airway pressure (CPAP) helmet on Lenin Peak

at 5300 m. Oxygen saturation wasinitially 56%, and the Lake

Louise Score was 13 of 15 points.

CJSM, Jan 2009

High-Altitude Pulmonary Edema

• If diagnosed early, pt. usually recovers.

• Mortality rate is 44%.

• Recurrence rate of HAPE in pts. w/ previous episode on subsequent climbs is 66%.

• Repeat ascent should not be attempted soon after episode. Can take up to 2 weeks to fully recover.

High-Altitude Cerebral Edema

• HACE constitutes the progression of HAPE or AMS to include involvement of the brain, causing encephalopathy.

• Cause is probably vasogenic cerebral edema, resulting from incr. intracranial pressure.

High-Altitude Cerebral Edema

• Symptoms:• Severe lassitude

• Altered consciousness

• Ataxia

• (+) Tandem Gait Test, Finger-to-nose not affected

• Focal neurologic signs are rare

• Symptoms worse at night

High-Altitude Cerebral Edema

• AMS may progress to HACE w/ unconsciousness w/in 12 hrs

• Usually takes 1 to 3 days to develop HACE

• MRI shows • Edema/generalized swelling

High-Altitude Cerebral Edema

• Treatment:• Immediate descent of at least 610m/2000ft, if sxs. does improve, descent

should continue.

• If descent is impossible:

• Oxygen at 2-4 LPM

• Dexamethasone (Decadron) 8mg initially then 4mg PO/IM q 6

• Portable hyperbaric therapy (as with HAPE)

• Post-HACE:• Sequelae can last weeks but eventually, pts usually recover completely.

• Mortality rate in untreated patient is 13%, up to 60% if they are comatose!

High-Altitude Retinopathy

• Related to hypoxia • manifested with cotton-wool exudates• tortuosity and dilation of retinal veins• visual scotoma

• Occurs at altitudes > 5,000m/16,000 ft

• Usually asymptomatic

• Resolves in 1-2 weeks, even if stay at elevation.

• Treatment:• Maintain good fluid intake to reduce hemoconcentration.• spontaneously resolves.

Ultraviolet Keratitis

• UV Keratitis (aka Snow-Blindness) occurs when bright sun reflects off snow causing corneal burns.

• Damage can occur in one hour, but sxs may not develop for 6-12 hrs.

• Can be prevent by wearing sun-glasses.

Ultraviolet Keratitis

• Symptoms:• Severe eye pain

• “Gritty” sensation in eyes

• Photophobia

• Tearing

• Chemosis

• Conjuctival erythema

• Eyelid swelling

Ultraviolet Keratitis

• Treatment: Remove contact lenses• Patching of the affected eye

• Rest

• Oral NSAIDs

• Topical ocular antihistamines/tetracaine for severe cases

• Resolves spontaneously w/in 24 hrs

• Watch for scratches 2o from rubbing & associated infxn

Peripheral Edema

• May develop in hands, face and ankles

• Treatment is with diuretics• Not in light of AMS, HACE, HAPE

• Condition spontaneously resolves on descent.

Vascular Complications

• Thrombotic Events:• Stroke, pulmonary embolus, DVT

• Combination of dehydration, polycythemia, cold, constrictive clothing.

• Bad weather can force long periods of inactivity leading to venous stasis.

• Treatment:• keep active, well hydrated, descend if needed

High-Altitude Pharyngitis & Bronchitis

• Almost 100% of climbers who stay 2 weeks at > 5,500m/18,000ft.

• Caused by the effect of cold, dry air on resp. mucosa esp w/ hyperventilation and mouth-breathing.

• Vasomotor rhinitis is common.

• Bronchitis can cause coughing fits, that are disabling and even fx ribs.

High-Altitude Pharyngitis & Bronchitis

• NOTE: symptoms are similar to HAPE

• Treatment:• Wear a face mask

• Suck on hard candy

• Drink plenty of fluids

Sickle Cell Anemia

• Patients should not ascend to high altitudes b/c they can have a crisis just at an elevation of 1,500m/4,900ft.

• Splenic infarct syndrome is more common at altitude.

• Incidence of problems in persons with sickle trait is low.

Coronary Artery Disease

• Not a significant risk between < 10,000 ft

• Pts w/ min. anginal sxs who are taking few medications & can exercise for > 9 minutes on a Bruce Protocol should be able to tolerate high altitude up to 12,000 ft.

Coronary Artery Disease

• Pts w/ HTN are not at incr. risk of AMS.

• Exercise tolerance at low alt. does not predict pt’s immunity from AMS at high altitude.

Asthma

• Many pts w/ asthma report improvement at altitude b/c lack of allergens.

• Some have increase in cold- or exercise- induced bronchospasm.

• FVC & FEV1 decline at altitude, due to incr. airway resistance.

Chronic Obstructive Pulmonary Disease

• Pts w/ mild COPD little problems at moderate or even high altitude.

• Pts. w/ moderate COPD should be careful b/c of risk of arterial desaturation and CO2 retention.

• Room air PaCO2 of < 50 mmHg AND a PaO2 of < 55 mmHg as contraindictation of airline travel (cabin press. = 2,440m/8000ft)

Pregnancy

• Exposure to moderate altitude does not seem to increase the incidence of:

• Spontaneous abortions

• Abruptio placentia

• Placenta previa

• Some advise against pregnant patients trekking in remote areas above 2,440m/8000ft.

Prevention

• Physical Fitness does not affect the incidence of AMS!!

• It does improve exercise tolerance and prevent HAPE & HACE by improving hemodynamic response to exercise.

• Keep HYDRATED!! force fluids.

• Avoid drugs or ETOH.

Altitude Training- “Live HIGH, Train Low”

• 2011 PAN AM GAMES: Rowing Venue was at Ciudad Guzman, Mexico at base of Zapotlan Volcano

• Where TEAM USA won Gold in ROWING

• Visited Mexican Training Center at 11,000 ft inside Caldera

Jen Goldsack, GOLD in single scullUS Men’s 8 wins GOLD

Altitude Training- Live HIGH, Train Low

• J. Dempsey from Univ of Wisconsin

• Hypoxia training (simulated Altitude training) has maladaptive effects to training in addition to adaptive one beneficial for training enhancement.

• He proposea hypoxia presents an insult to O2 transport, which is poorly tolerated in most humans because of the physiological cost.

Dempsey et al, Physiology (Bethesda). 2015 Jul;30(4):304-16

Graded Ascent

• Used on expeditions to acclimatize.

• DAY 1: Rest below 2,440m/8000ft

• DAY 2: Ascend 305m/1000ft

• DAY 3: Ascend 305m/1000ft

• DAY 4: Ascend 305m/1000ft• every third night, spend two nights here

Staged Ascent

• Involves traveling to an intermediate altitude and camping for several nights.

• Example:

• Going from 3,000m to 4,300m (10,000ft to 14,000ft) should acclimatize at at 1,800-2,500m (6,000-8,000 ft) for two to four days before continuing the ascent.

Descent

• Descent should be undertaken is sxs occur

• “Climb High, Sleep Low”• sleep at night should take place at least 460m/1500ft lower than altitude

climbed that day.

Prevention

• Pharmacotherapy:• Acetazolamide can reduce severity of AMS.

• 250 to 1,000 mg per day.

• Starting 12-24 hours before ascent.

• Continue for 3-4 days.• Dexamethasone can prevent and treat AMS & HACE.

• Side-effects include euphoria and glucosuria.

• Use only in Diamox-intolerant or Sulfa-allergic.

World Wide Web

• Himalayan Rescue Association Nepal home page at: • http://www.himalayanrescue.org/

• Lake Louise 1991 High Altitude Symposium Criteria• http://www.high-altitude-medicine.com/AMS-LakeLouise.html

• International Hypoxia Symposium 2015 Lake Louise• http://online.liebertpub.com/doi/full/10.1089/ham.2015.0046

• Bengt K, “The International Hypoxia Symposium 2015 in Lake Louise: A Report,” High Altitude Medicine & Biology. September 2015, Vol. 16, No. 3: 261-266

•

Thank You

TEAM USA at IWF Youth World Weightlifting Chsmpionships in Penang, Malaysia October 2016

References

• Fiore, Hall, et al; “Altitude Illness; Risk Factors, Prevention and Treatment,” Am Fam Phys Vol 82(9) p1103-1110; 11/1/2010.

• Harris, M,. Terrio J., Miser, W., Yetter, J. High-Altitude Medicine, American Family Physician, April 15,1998, vol. 57(8), pp. 1907-1914.

• Bezrucchka, S., High Altitude medicine. Med clin North Am 1992;76:1481-97.

• Zafren, K., Honigman, B., High-altitude medicine. Emerg Med Clin North Am 1997;15191-222.

• McMurray, S. High Altitude Medicine for Family physicians. Can Fam Physician 1994; 40:711-8.