ALTITUDE SICKNESS
Colin M. Fuller, MD, FACC, FACP
Altitude definition
High altitude
1,500m – 3,500m
5,000’ – 11,500’
Very high altitude
3,500m – 5,500m
11,500’ – 18,000’
Extreme altitude
> 5,500m
> 18,000’
High altitude medical problems
Acute hypoxia
Acute mountain
sickness (AMS)
High altitude
pulmonary edema
(HAPE)
High altitude
cerebral edema
(HACE)
Ravenhill (1913) paper in South American
literature
1. Revealed his observation
of people transported from
sea level to 16,000’ by train
in Bolivia.
2. Most all developed mild
symptoms hours after arrival:
poor sleep, HA, anorexia,
lassitude, symptoms
increased with exercise,
decreased with rest.
Resolved over four days,
called it “normal puna.”
Rave
nhill
Ravenhill noted 2 very serious divergences from
normal puna
“Cardiac puna” – ↑ SOB, ↑ pulse, ↑ RR, cyanosis,
occasionally leads to death
“Nervous puna” –
dizziness, difficulty
with gait, delirious;
rare – often fatal
Rave
nhill
Case report of HAPE from Bates, F. Circulation,
25:929, 1962 T.B., 48 y/o physician, experienced
skier and mountaineer in good health, rode from
sea level to 8,500’ (Alta, Utah) over 12°. Skied
vigorously x 2 days between 8,500’ + 10,300’.
2nd night –
c/o SOB +
nonproductive
cough.
HAPE
Next morning, Sx worse. Also c/o N,V, dizziness
+ HA. ASA + codeine: ↓ cough + H.A., but by
noon Sx ↑. Next day, pt barely able to speak 2°
to SOB, cough now produced pink frothy
sputum. Pulse 120, R.R. 50, therefore, pt
referred to local
hospital (4,200’).
HAPE
Admission to hospital:
• apprehensive, breathless, cyanotic
• Pulse 110 BP 130/90 T° 99°F
• Heart-fixed split of S2
• Lungs – basilar
rates
hct = 51 WBC = 9,800
ECG = Sinus tach PO2 = 40
CXR = normal heart size
pulmonary edema
Rest of work-up was (-) for infection, myocardial
infarction, or intrinsic heart disease
Over next 4 days pt. returned to normal status
The following year pt. returned to high altitude +
Sx recurred
AMS – setting
Generally rapid ascent of unacclimatized persons to ≥
2,500m (8,200’) from altitudes below 1,500m (5,000’)
AMS – pathophysiology
Brain edema?
Secondary to ↓ PO2
AMS – physical exam
Not much data
Probably normal
Moderate acute mountain sickness - Rx
Low-flow oxygen, if available
Acetazolamide, 125 to 250 mg b.i.d., with of without
dexamethasone, 4 mg po, IM, or IV q6h
Hyperbaric
therapy or
immediate
descent
AMS – prevention
Slower ascent
Diamox
Past predicts
future
HAPE – mild
Symptoms
DOE
Dry cough
Signs
HR (rest) < 90
RR (rest) < 20
Few rales, if any
Symptoms Signs
Severe DOE HR 90 – 100, Cyanosis, Rales, Ataxia
Weakness
Headache
Cough
HAPE – moderate
Symptoms Signs
Dyspnea at rest HR > 110, RR > 30, Diffuse rales
Productive cough Blood-tinged sputum, Ataxis, stupor
Orthopnea
Extreme weakness
HAPE – severe
HAPE – treatment
Early recognition
O2, Pressure bag
Nifedipine?
HAPE – prevention
Slow ascent
Drugs – not known
Past predicts future
Early diagnosis is key
HAPE – sequelae
1 – 8 days for Sx to subside
• Lungs and circulation – No chronic sequele
• Re-ascent
usually leads
to HAPE again
HAPE on Mt. Everest, 1990
HAPE on Mt. Everest, 1990
HAPE on Mt. Everest, 1990
Before Echo Contrast Injection
After Echo Contrast Injection
HACE – High Altitude Cerebral Edema
Progression of global cerebral signs and symptoms in
the setting of AMS
HACE – pathophysiologyIncreased H2O in brain cells swelling of cells in rigid
box Sx
HACE – setting>11,000
Rare
May occur
with or be
sequel to
HAPE or
severe AMS
HACE – historySevere HA; Hallucinations; Considerable dizziness
Difficulty with respirations; Staggering; Double vision
Delirium; Paralysis; Proceeding to coma + death
HACE – physical exam
Not much data
Poor coordination
Mental status abnormalities
HACE – prevention
Slow ascent
Early diagnosis: clumsy skier
Drugs – none known to be of prophylactic value
HACE – treatment
Recognition
Descent
Dexamethazone
O2
Pressure bag
Other high altitude medical
problems
• Disordered sleep
• Retinopathy
• UV keratitis
• Peripheral edema
• Pharyngitis/Bronchitis
• HAFE
• Thromboembolic
problems
Retinal hemorrhage (R.H.)
Setting:
20 – 30% ascending ≥ 14,000’
Appears to be exacerbated by
strenuous exercise
R.H. – pathophysiology
Etiology not clear
No correlation with
1) Headache
2) Speed of ascent
3) Sx of AMS
R.H. – history
Usually Asymptomatic
Sudden loss or blurring
of vision in one eye
R.H. – physical
exam
Ophthalmoscope
necessary
R.H. – treatment
Descent
Drugs – none known
R.H. – prevention
None known
Periodic breathing - RxAcetazolamide, 62.5 to 125 mg at bedtime as needed
Ultraviolet keratitis (snow blindness)
One week S/P UV
keratitis
Summit of Everest
Advisability of exposure to high altitude –
no extra risk
Young/old, Fit/unfit
Low risk pregnancy
Controlled hypertension
Obesity
Controlled seizure disorder
Diabetes
Psychiatric disorder
Mild COPD, Asthma
Neoplastic diseases
Inflammatory diseases
Post-CABG (no angina)
Advisability of exposure to high altitude –
caution
Moderate COPD
Angina
Compensated CHF
High risk pregnancy
Sleep apnea
Sickle cell traits
Troublesome arrhythmia
Advisability of exposure to high altitude –
contraindicated
Sickle cell anemia with Hx of crisis
Severe COPD
Pulmonary hypertension
CHF not well controlled
Cerebrovascular disease
Questions? Comments?
Thank you!
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