By : Aamarpali Puri
Decompression sickness or The Bends, or Caisson disease, is mainly found in scuba divers or people participating in high altitude or aerospace events when dissolved gases (mainly nitrogen) come out of solution in bubbles and affects human body area including joints, lung, heart, skin and brain. The bubbles of gas formed due to change in pressure during Scuba diving. Astronauts and aviators that experience rapid changes in pressure from sea level also experience bends.
SCUBA stands for Self Contained Underwater Breathing Apparatus. It is different from holding breadth and diving. In this type of diving, the diver under deep sea water carries air tank. The gas in the air tank increases in pressure as the divers descends. Gases like nitrogen cause increased pressure and get dissolved into the tissues of the diver’s body. The human can’t consume nitrogen so it gets accumulated in the tissues. When the diver returns to sea surface, then the pressure decreases. The Nitrogen gas tries to leave the tissues and come out as bubbles which lead to blocking of blood flow. Stretching or tearing off nerves may happen. Occurrence of Bends is dependent on the depth and duration of the dive. It leads to extreme fatigue, deafness, rashes, itching. It may choke lungs and cause back pain. Drinking alcohol before diving causes our brain at risk of injury due to nitrogen bubbles. The worst affected area is spinal cord. Providing high flow of oxygen helps in fast recovery. Diving deeper then recommended level and staying deep sea for more duration increases the risk to great extent. Flying immediately after diving is very dangerous. Diver while returning back to sea level should rise up slowly not very fast. In very serious conditions the person is kept in hyperbaric oxygen chambers where the nitrogen is again dissolved back to the tissues and can then get metabolized normally.
It can be avoided by learning the following:
- How long should diver stay under water?
- How deep diver can go in sea?
- How much time diver should take while returning back to sea level?
- How much gap should be kept between consecutive dives?
- After how much time diver can board flight?
Some other diseases deep sea diver may encounter are Nitrogen Narcosis or Rapture of the deep, Air Embolisms, Pneumothoraces and Bad Air Injuries.
Nitrogen Narcosis: At depths greater than 100 feet breathing nitrogen leads to intoxicating effect (“temporary decline or loss of senses and movement, numbness) which is known as Nitrogen Narcosis. Breathing nitrogen under high pressure causes difficulty in concentration, poor judgment hallucination.
Air Embolism: Person suffering from water stress suffers from this condition. In this a gas bubble enters vascular system and cause blockage in blood vessels.
Pneumothoraces: It is found mainly in person suffering from lung disease which might be expected to cause gas trapping during ascent in divers. It occurs more frequently in divers whose lungs are small and stiff. In extreme cases it leads to lung rupture.
Bad air Injuries: It includes carbon dioxide, carbon monoxide poisoning. If the diver inhales contaminated gases, most commonly carbon monoxide, when faulty air compressor leaks harmful fumes into diver’s tank, Haemoglobin is unable to transport the oxygen properly in the tissues. Even the high percentage of inhaled oxygen over prolonged period may be harmful.