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Mountaineering
Medicine
G
Podolsky MD
Unique
Considerations
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Mountain Environments
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High Altitude Illness
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Hypothermia
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Remoteness of Help
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Difficulty in Evacuations
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Cultural Issues
Educating
Adventurers on Wilderness Medicine
Topics
Evaluate:
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Health baseline & exotic considerations
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Pre trip planning
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Ounce of prevention better than pound of cure
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(pound of prevention also better than an oz of prevention)
High
altitude is defined as:
-High
Altitude: 1500 - 3500 m (5000 - 11500 ft)
-Very
High Altitude: 3500 - 5500 m (11500 - 18000 ft)
-Extreme
Altitude: above 5500 m
Practically
speaking, however, we generally don't worry much about elevations
below about 2500 m (8000 ft) since altitude illness rarely occurs
lower than this.
Certain
normal physiologic changes occur in every person who goes to altitude:
-Hyperventilation
(breathing faster, deeper, or both)
•
-Shortness of breath during exertion
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-Changed breathing pattern at night
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-Awakening frequently at night
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-Increased urination
Periodic
Breathing
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Periodic breathing consists of cycles of normal breathing, which
gradually slows, breath-holding, and a brief recovery period of
accelerated breathing. The breath-holding may last up to 10-15 seconds.
•
This is not altitude sickness. It may improve slightly with acclimatization,
but does not usually resolve until descent. Periodic breathing can
cause a lot of anxiety:
Case
Study
Acute
Mountain Sickness in Himalayan Plateau on pass to Lhasa
Periodic
breathing, Irritability,decreased decision
Importance
of prevention, recognition and immediate action
High
Altitude
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Breathing Rarified air
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Less oxygen per breath
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Leads to Respiratory alkalosis
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After several days kidneys compensate and excrete bicarbonate leading
to respiratory alkalosis with compensated metabolic acidosis
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Altitude illness result of disequilibrium of blood gasses and membrane
effects
Acute
Mountain Sickness (AMS)
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This diagnosis is made when a headache in anyone, or more of the
following symptoms is present after a recent ascent above 2500 meters
(8000 feet):
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- Loss of appetite, nausea, or vomiting
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-Fatigue or weakness
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-Dizziness or light-headedness
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-Difficulty sleeping
High
Altitude Cerebral Edema (HACE)
Symptoms
may include:
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Difficulty walking
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Decreased coordination
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Coma and possible death
First
Aid in Other Countries?
Surviving
HACE
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People with HACE usually survive if they descend soon enough and
far enough, and usually recover completely. The staggering gait
may persist for days after descent.
•
If recovery has been complete, and there are no symptoms
, cautious re-ascent is acceptable.
Treatment
of HACE
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Immediate descent is the best treatment. This is of the utmost urgency,
and cannot wait until morning (unfortunately, HACE often strikes
at night). Delay may be fatal. The moment HACE is recognized is
the moment to start organizing flashlights, helpers, porters, whatever
is necessary to get this person down. Descent should be to the last
elevation at which they woke up feeling well. T he majority
of cases of HACE occur in persons who ascend with symptoms of AMS
,
Other
Treatments of HACE
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Treatment includes immediate
•
DESCENT,
•
DESCENT,
•
and DESCENT.
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Oxygen , Gamcow bag , and Dexamethasone are also useful but are
not a substitute- this is not a condition that should be treated
on the mountain.
High
Altitude Pulmonary Edema (HAPE)
•
High Altitude Pulmonary Edema (HAPE) Another form of severe altitude
illness is High Altitude Pulmonary Edema, or fluid in the lungs.
Though it often occurs with AMS, it is not felt to be related and
the classic signs of AMS may be absent.
•
Needs urgent treatment.
Signs
and Symptoms of HAPE include:
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-Extreme fatigue
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-Breathlessness at rest
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-Fast, shallow breathing
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-Cough, possibly productive of frothy or pink sputum
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-Gurgling or rattling breaths
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-Chest tightness, fullness, or congestion
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-Blue or gray lips/fingernails
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-Drowsiness
Immediate
descent is the treatment of choice for HAPE
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Oxygen must be available- delay may be fatal. Descend to the last
elevation where the victim felt well upon awakening. Descent may
be complicated by extreme fatigue and possibly also by confusion
(due to inability to get enough oxygen to the brain); HAPE frequently
occurs at night, and may worsen with exertion. These victims often
need to be carried.
•
It is common for persons with severe HAPE to also develop HACE,
presumably due to the extremely low levels of oxygen in their blood
(equivalent to a continued rapid ascent).
HAPE
Follow-up
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HAPE resolves rapidly with descent, and one or two days of rest
at a lower elevation may be adequate for complete recovery. Once
the symptoms have fully resolved, cautious re-ascent is acceptable.
•
HAPE can be confused with a number of other respiratory conditions
Cough
at Altitude
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High Altitude Cough and Bronchitis are both characterized by a persistent
cough with or without sputum production. There is no shortness of
breath at rest, no severe fatigue.
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Pneumonia can be difficult to distinguish from HAPE. Fever is common
with HAPE and does not prove the patient has pneumonia.
Coughing up green or yellow sputum may occur with HAPE, and both
can cause low blood levels of oxygen. The diagnostic test (and treatment)
is descent - HAPE will improve rapidly. If the patient does not
improve with descent, then consider antibiotics. HAPE is
much more common at altitude than pneumonia, and more dangerous;
many climbers have died of HAPE when they were mistakenly treated
for pneumonia.
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Asthma might also be confused with HAPE. Fortunately, asthmatics
seem to do better at altitude than at sea-level. If you think it's
asthma, try asthma medications, but if the person does not improve
fairly quickly assume it is HAPE and
treat it accordingly.
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Tuberculosis (Long term visits are at risk)
Other
Altitude Problems
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High Altitude Retinal Hemorrhage
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Chronic Mountain Sickness (Maladaptive Polycythemic Condition)
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Asthmatics often may do better in cool clean mountain air
Who
Should Not Travel To Altitude
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Unstable Cardiovascular Diseases
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Age itself is not a contraindication
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Sickle cell and related hemoglobin diseases
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Undiagnosed cardiac anomalies
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Anomalous Pulmonary Artery
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Pulmonary Hypertension
Must
consider fitness of individual as a whole to evaluate risk
Uncomplicated
Pregnancy
No
Reason Not To Restrict Travel
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Many normal deliveries at altitude
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Some studies note increased risk of stillbirth but not this is still
controversial
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More importantly is mothers access to good obstetric care before
and during trip
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High risk pregnancies should NOT go to remote areas with limited
access Children at Altitude
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No greater risk but also susceptible to altitude
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Are non communicative
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Modified Lake Louise score to assess children
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Look for irritability and poor feeding as a sign of altitude illness
Exercising
at Altitude
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Exercise stimulates the process of erythropoiesis. Legally increasing
red blood cell mass.
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This gives a greater oxygen carrying capacity for increased performance.
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Residents at altitude have normal hematocrit. Population genetics
have allowed them to have Hemoglobin groups that are more efficient
at high altitude
Avoiding
Problems at Altitude
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Gradual Ascension
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Maintain Hydration
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Avoid over exertion
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High carbohydrate diet
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No evidence of protective effect of ginger or coca leaf.
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Caffeine may dehydrate
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Alcohol and drugs bad news in wilderness
Ultraviolet
Radiation at Altitude
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Increased risk of cancer and photoaging in developing nations ie;
Nepal
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Many residents of 3 rd World oblivious to risks and travelers follow
this example.
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Need Hat + Clothes + Sun block
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Fast action on premalignant skin changes
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Travelers often don t consider risk of UV when on holiday
UV
Protection At Altitude
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Mountain travelers should have good clothing, hats, eyeglasses,
and sunscreen.
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Suntanning salons to acquire a base tan is worthless.
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Recent studies have shown that suntanning salons cause more cancer
than regular sunlight.
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(Canadian Dermatology website www.cda.com
)
Ethical
Mountain Travel
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Respect of local people
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Issues of exploitation
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Porters -many inexperienced villagers present themselves as Sherpas
(who may be less prone to altitude problems) risking their lives.
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Use of resources (trekkers supply own kerosene and don't burn vanishing
wilderness)
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Sexual Tourism
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Pollution (pack out wastes, garbage, O2 cylinders)
The
Three E's of Emporiatrics
Entertainment
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Traveling to a country for amusement and recreation
Education
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Learning the history, geography, and society of the country
Enlightenment
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Understanding the uniqueness and value of other cultures.
Podolsky,
2002
Hypothermia
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Cold mountain top
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Warm valleys
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Also snow and rainfall
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Need clothing that supports a variety of conditions
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"mountaineers use mittens with a string tied"
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Extra pair of socks handy- "poor man's mittens"
Carbon
Monoxide Poisoning
Also
confused with altitude related difficulties
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Headache worse at night
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Associated with stoves and poor ventilation
Mountaineering
First Aid Kit
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Diamox (acetazolamide) 125 mg twice daily for prevention. 250mg
twice daily for treatment
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Decadron Used for prevention (uncommon and dangerous since this
drug will wear off) and treatment of AMS and HACE
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Nifedipine for treatment or prevention of HAPE
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Viagara New off label use 0 relaxes pulmonary vessels. Dose 1 pill
once daily.
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Ciprofloxacin- travelers diarrhea a problem even at altitude
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Immodium
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Tylenol or ASA for mild complaints differentiate non AMS headaches
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Stool softeners / Laxatives
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Sun block and sunglasses
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Ventolin useful for smoke inhalation
Responsibility
of Mission
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Ensure Safety Of All Members
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Evacuation Plan And Commitment To Follow Through
Duty
To Outfit Porters:
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Food
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Clothing and footwear
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Shelter
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Medical care
How
To Access Help
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Department of foreign affairs
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Helpful websites
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Learn about culture in advance
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International Society Of Travel Medicine
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Linkage to members from their website
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For more information please check our website www.skylarkmedicalclinic.com
(a downloadable algorithm for the self diagnosis of altitude
illness is listed)
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or the following excellent resources:
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www.voyage.gc.ca Canadian
Department of Foreign Affairs
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International Society of Mountain Medicine
Conclusions
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Being fit helps but no guarantee
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Must proceed with caution
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Everyone must know signs and symptoms of AMS, HAPE, and HACE
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Must have plan and resolution to follow through- do not pass the
"point of no return"
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Most disasters are not random but consequences of poor planning
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Mountaineering must also consider problems with nutrition, clean
water, hypothermia, accidents, injuries, and interacting with indigenous
peoples.
Let
our patients take care of the adventure and we'll take care of them.
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