Ebullism

As ebullism (of lat. Ebullire = gush) the bubble out of gases (especially nitrogen) is referred to in the blood and tissues. This can be done by rapid pressure drop, e.g. B. when surfacing quickly from deep water. The main problem is the nitrogen dissolved in the blood because of its high proportion of 78% in the air we breathe . Ebullism is the cause of decompression sickness (also known as caisson disease, diving disease or aeroembolism).

Symptoms

Symptoms of ebullism include bubbles in the membranes in the mouth and eyes, swelling of the skin, and air bubbles in the blood. The evaporation also creates a strong cooling effect at these points. Blood flow and breathing are severely impaired or stopped. Because of the air bubbles in the arteries, the brain tissue can no longer be adequately supplied with oxygen.

Space travel

In order to prevent ebullism, a pure oxygen atmosphere was used in early space travel, which, however, entails an increased risk of fire. After the fire accident in the Apollo 1 capsule, the atmosphere in spacecraft was replaced by a nitrogen-oxygen mixture during all work prior to the launch and the launch phase and only changed to a pure oxygen atmosphere again in orbit.

Armstrong limit

See also : Armstrong limit

In addition to the release of dissolved gases, there is another problem at high altitudes: At an altitude of 18,900 to 19,350 m (atmospheric pressure 6.3 kPa or 0.0618 atm ), water already boils at 37 ° C, the normal human body temperature. In the aerospace industry, this limit, at which the air pressure becomes so low that the blood would boil at body temperature without a pressure suit , is referred to as the Armstrong limit (after the aviation doctor Harry George Armstrong, 1899-1983). In practice, the boiling of body fluids does not yet occur at exactly this level because the skin and tissue keep the pressure inside the body above the external pressure. However, the formation of bubbles in the blood is a serious medical problem.

Individual evidence

1. ↑ Ebullism. In: Pschyrembel Online. April 2016, accessed January 11, 2019 . 
2. ^ Pschyrembel clinical dictionary: With clinical syndromes and nouns anatomica . Walter de Gruyter, 2012, ISBN 978-3-11-150689-0 ( google.de [accessed on October 20, 2018]).
3. ↑ Jeffrey R. Davis, Robert Johnson, Jan Stepanek: Fundamentals of Aerospace Medicine. 4th edition. 2008, p. 252.
4. ^ Geoffrey A. Landis: Human Exposure to Vacuum. (accessed on January 16, 2013).

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !