At Deep Sea

Question 1

dysbarism or decompression sickness or caissons disease

Answer 1

This is a condition that is seen in divers who work at great depths of the sea for long periods and when they come rapidly to the surface.

Genesis:- When a diver is working at the depth of sea, he is exposed to high barometric pressure (barometric pressure rises by 1 atmosphere for every 33 feet descent) and therefore he has
to breath air or any other gas at high pressure to prevent collapse of chest. If he breathes air (80% nitrogen) at
high pressure. large amounts of N2 gets dissolved in his body fluids especially in the lipids of nervous system because N2 is more soluble in lipids than in water. Excess N2 in brain neurons produces alcohol like effects called Nitrogen narcosis. When this diver rapidly comes to the surface of the sea, his body is suddenly decompressed

Therefore, the dissolved N2 become less soluble and comes out of solution in the form of bubbles in the tissues (similar to opening of a soda water bottle) producing, various symptoms.

Manifestations :-

1) Acute pain in bones and joints (especially elbow) called bans. It is due to N2 bubbles in periosteum
2) Sensation of choking (chokes) due to bubbles in pulmonary capillaries.
3) Tingling, numbness and loss of sensation (bubbles in myelin sheath)
4) Paralysis of muscles.
5) Angina pectoris or cardiac arrhythmias (bubbles in coronaries)
6) Sometimes serious complications like coma, respiratory failure, permanent mental damage etc. are seen.

Treatment :- Prompt recompression of the subject in a compression chamber followed by gradual stepwise decompression. Oxygen administration if required.

Prevention :-

1. Gradual stage wise ascent with some time spent at each stage.
2. By use of Helium-oxygen mixture instead of air. Helium is less soluble and more diffusible.