Hape and hace from altitude sickness

Acute Mountain Sickness-Symptoms and Treatment

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Acute Mountain Sickness (AMS)

Acute exposure to low partial pressure of oxygen at high altitude

It commonly occurs above 2,400 meters (8,000 feet)

Resembling a case of flu or a hangover

Acute Mountain Sickness Cause

The air density or the number of molecules (of both oxygen and nitrogen) per given level, which drops as altitude increases

Dehydration due to the higher rate of water vapor lost from the lungs at higher altitudes also contribute to the symptoms of altitude sickness.

Acclimatization-putting extra red blood cells into your blood stream

People can experience similar symptoms during air travel (Cabin pressurized similar to 3,000 meters)



Acute Mountain Sickness Symptoms

Digestion• Lack of appetite, nausea, or vomiting

Brain• Fatigue or weakness• Dizziness or lightheadedness• Insomnia• Persistent rapid pulse

Respiratory• Shortness of breath upon exertion• Drowsiness

Peripheral edema (swelling of hands, feet, and face).

Acute Mountain Sickness Prevention

Ascent graduate. Start the rise below 3000m A night of acclimatization every 1000 meters Abundant hydration (5 liters/day) 70-80% carbohydrate diet to achieve higher

blood oxygen levels• Blood Oxygen Levels vs. blood carbohydrate levels• Tissues consume oxygen in proportion as they utilize

glucose. Therefore, in the presence of low blood sugar, the tissues will consume less oxygen and so suffer an oxygen lack (Wortis, 2001)


Acetazolamide -administered 1 day before ascent and continued for 2 to 3 days is effective (Hackett and Roach, 2001)• A large clinical trail from Nepal showed 125 mg of the

Acetazolamide twice daily is effective and bigger doses offer no significant benefit (Dasmat et al, 2006)


Acetazolamide• Carbonic anhydrase (CA) inhibitor• CO2 + H2O <--CA--> H2CO3 <--> H+ + HCO3

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• Forces the kidneys to excrete bicarbonate, this re-acidifies the blood, balancing the effects of the hyperventilation that occurs at altitude in an attempt to get oxygen.

• It suppress respiratory alkalosis. This re-acidification acts as a respiratory stimulant


Dexamethasone 8 mg/day in divided doses may be used (Rock et al, 1989)• Does not help in acclimatization. Symptoms may occur

after stoppage of drug (Hackett et al, 1988)

Acute Mountain Sickness Therapy

Mild AMS• Discontinue ascent. Rest and acclimatize• Speed up acclimatization with Acetazolamide 250 mg 12

hourly• Go down if symptoms continue

Moderate AMS• Go down• Hyperbaric chamber if decent not possible• Acetazolamide 250 mg 12 hourly or Dexamethasone 8

mg/day

High Altitude Pulmonary Edema (HAPE)

HAPE is due to general vasoconstriction in the pulmonary circulation which, with constant or increased cardiac output, will leads to increases in capillary pressures.

The blood vessels more prone to fluid leakage. This fluid leakage into the alveoli of the lungs interferes with respiration


Fluid in the lungs Symptoms similar to bronchitis Persistent dry cough Fever Shortness of breath even when resting


Immediate Descent, preferably by at least 1000 meters.

Oxygen should also be given if possible @ 4-6L/min

The standard drug treatments for which there is strong clinical evidence are • Dexamethasone 8 mg/day • Nifedipine 15 mg first then 20 to 30 mg every 12 hours• Phosphodiesterase inhibitors such as Tadalafil (but may

worsen the headache of mountain sickness)

High Altitude Cerebral Edema (HACE)

HACE is caused by local vasodilation of cerebral blood vessels in response to hypoxia, resulting in greater blood flow and, consequently, greater capillary pressures


Swelling in the brain Headache Gradual loss of consciousness Increased nausea Retinal hemorrhage


Immediate Descent Oxygen administration @ 4-6L/min Dexamethasone will also temporarily alleviate

symptoms, which is the necessary life-saving measure.

Hyperbaric bags are highly effective in conjunction with dexamethasone

Health & Medicine

Hape and hace from altitude sickness