Having walked on the moon, former astronaut Buzz Aldrin knows a thing or two about visiting dangerous environment. It still didn’t prepare the 86-year-old for the conditions he faced during his recent excursion to the South Pole. After reaching the pole, Aldrin began to experience difficulty breathing. Physicians with the group were concerned that he was experiencing high altitude pulmonary edema. He was evacuated first to McMurdo Station, on the Antarctic coast. A second flight took him to a hospital in Christchurch, New Zealand.
He “currently has fluid in his lungs but is responding well to antibiotics and being kept overnight for observation. His condition is stable and his manager Christina Korp, who is currently with him, described him being in good spirits.”
Scott Parazynski, a five-time shuttle astronaut, who once oversaw healthcare for the US Antarctic Program told CNN:
“Many visitors to the Amundsen-Scott South Pole Station have difficulty with the abrupt change in altitude — depending on the temperature and atmospheric pressure, it can feel like 11,000 feet above sea level, where there’s a dramatic reduction in the amount of oxygen in each breath. “High altitude-related illnesses, including Acute Mountain Sickness (AMS) and less commonly High Altitude Pulmonary Edema (HAPE) have been reported in new arrivals to the station, in some cases requiring medical evacuation to McMurdo Station and points north.
(Source: Medline Plus and CDC)
There two types of high altitude illesses, Acute Mountain Sickness (AMS) and High Altitude Pulmonary Edema (HAPE). Both can affect mountain climbers, hikers, skiers, or travelers at high altitude (typically above 8,000 feet or 2,400 meters). It is brought on by the combination of reduced air pressure and lower oxygen concentration that occur at high altitudes. Symptoms can range from mild to life-threatening, and can affect the nervous system, lungs, muscles, and heart.
In most cases the symptoms are mild. In severe cases fluid collects in the lungs (pulmonary edema). The extra fluid can “drown” the patient by impairing the normal gas exchange with the circulating blood and can cause respiratory failure. This further reduces how much oxygen enters the bloodstream and reaches vital organs and tissue. Symptoms include extreme shortness of breath, a feeling of suffocating or drowning, frothy, possibly blood-tinged sputum, paleness, and excessive sweating. Brain swelling may also occur (cerebral edema). This can cause confusion, coma, and, if untreated, death.
The chance of getting acute mountain sickness increases the faster a person climbs to a high altitude. How severe the symptoms are also depends on this factor, as well as how hard the person pushes (exerts) himself or herself. People who normally live at or near sea level are more prone to acute mountain sickness.
Approximately 20% of people will develop mild symptoms at altitudes between 6,300 to 9,700 feet, but pulmonary and cerebral edema are extremely rare at these heights. However, above 14,000 feet, a majority of people will experience at least mild symptoms. Some people who stay at this height can develop pulmonary or cerebral edema.
The main form of treatment for all forms of mountain sickness is to climb down (descend) to a lower altitude as rapidly and safely as possible. Extra oxygen should be given, if available.
Acetazolamide (Diamox) is a drug used to stimulate breathing and reduce mild symptoms of mountain sickness. This drug can cause increased urination. When taking this medication, make sure you drink plenty of fluids and do not drink alcohol.
Pulmonary edema, the build-up of fluid in the lungs, is treated with oxygen, the high blood pressure medicine nifedipine or phosphodiesterase inhibitors (sildenafil). In severe cases, a breathing machine (respirator) is used.
The steroid drug dexamethasone (Decadron) may help reduce swelling in the brain (cerebral edema).
Portable hyperbaric chambers have been developed to allow hikers to simulate their conditions at lower altitudes without moving from their location on the mountain. These new devices are very important if bad weather or other factors make climbing down the mountain impossible.