Effect of high pressure at depth on the nervous system

In the summer, many people go to the sea or the ocean to relax. Someone enjoys swimming and gets a beautiful tan, while someone likes to dive. Diving – not only a cognitive and interesting process, but it also carries many threats to human health, and can even lead to fatal consequences. What are the dangers of diving? What should a person who is going to dive into the depths know? And how to prevent the dangerous effects on the body of the forces of nature, read on estet-portal.com.

Atmospheric pressure at depth causes decompression sickness

    At the top of Mount Everest with a height of 8848 m, the pressure of the atmosphere decreases by two-thirds, and when immersed in water to the same depth, atmospheric pressure at a depth increases by 885 times! Naturally, water is much heavier than air. In sea water, with each descent of 10 m, the pressure at depth becomes more and more. So, already at a depth of 30 m, when diving, a person experiences a pressure of  4 bar. With a sharp rise from a high-pressure zone at depth, a diver under normal atmospheric pressure gets decompression sickness. Decompression sickness is manifested by skin itching and severe pain in the joints and muscles. With sharper rises from a depth, dizziness, paralysis of the whole body, loss of consciousness, death may occur. It all happens in a few minutes.

 The formation of deadly bubbles. Diving hazard

    After diving, with a rapid ascent from a depth, the following processes occur in the body: gases from the blood and tissues of the body are released in the form of bubbles. The formed bubbles continue their growth process, using new portions of gas. As a result, these bubbles grow to such a large size that they can clog the vessels and provoke the development of a gas embolism. This process prevents the flow of blood with oxygen to the cells, and they die. After diving, the formed air bubbles during a sharp rise also activate the production of platelets, which react to the addition of air in the vessels, blood clots form. When air bubbles form inside the tissues, the tissues can be damaged or torn. Experienced divers have experienced the effect of these bubbles. interruptions in breathing that appear after diving, are due to the formation of bubbles in the capillaries of the lung tissue, while their respiratory volume is reduced. When the bubbles of the vestibular apparatus are affected, the balance is disturbed. Violation of blood circulation in the nervous structures after diving manifests itself in the form of paresis or paralysis, impaired sensitivity and speech.

What are the dangers of diving dental fillings?

    When diving, there is a reduction in the volume of gases, and when rising to the surface, they expand. That is, when diving, the gases that are in the body cavities are compressed under pressure, and then dissolved in liquids. If this compression occurs too quickly, the eardrum may rupture while diving. And if suddenly a small air bubble remains in the dental filling during the treatment of the tooth, then when it is compressed at a depth, implosion (an explosion directed inwards) can occur in the same filling. And at high altitude, the opposite can happen – under reduced pressure, a tooth containing an air bubble may rupture inside.

Influence of high pressure at depth on the nervous system

     At a pressure of 21 bar on a person at a depth of 200 m, people develop the so-called high pressure nervous syndrome (“shaking”). This syndrome is manifested by trembling, dizziness, nausea and microsleep - a short-term loss of attention. This syndrome puts a limit on the diver's diving depth. With an oxygen-helium mixture, this limit is 200-250 m, and if nitrogen is added to this mixture, a person will be able to withstand pressure at a depth of up to 450 m in the open sea. The lower safe limit when diving with compressed air is considered to be a depth of 30 m. When diving, there is a danger of nitrogen narcosis. This is because divers who breathe compressed air form nitrogen bubbles in their blood.

Nitrogen intoxication. Nitrogen narcosis while diving

    When diving and a person is under high pressure of several atmospheres, nitrogen always causes intoxication, which is very similar to alcohol intoxication. There is euphoria, detachment from reality, increased arousal, loss of coordination. Nitrogen narcosis occurs when diving to a depth of 50 m, and as the depth increases, the symptoms increase. Already after 90 m loss of consciousness is possible. With frequent diving to depth, the body adapts to the action of nitrogen, but, with all this, nitrogen intoxication is still the cause of death of many divers who dived to a depth of 50 meters.

Oxygen poisoning is possible when diving to depth

    Pure oxygen is a dangerous substance, the toxicity of which only increases under pressure. A person can breathe pure oxygen for about 12 hours at a pressure of 1 atm, after a day the alveolar cells in the lungs are destroyed. In this case, a person develops a cough after diving, and fluid may accumulate in the lung tissue. At a pressure of 2 atm, a person experiences nausea, dizziness. After a few hours, convulsions begin, which are similar to an epileptic seizure. At a pressure of 7 atm, it is possible to breathe pure oxygen for only 5 minutes, and then convulsions begin. In this case, oxygen becomes sweet and sour in smell and resembles, according to divers, the smell of ginger beer or diluted ink with sugar.

Diving precautions and advice for people in dangerous professions at depth

     Even if a person has been under the influence of high pressure at depth for several minutes, it is worth ascending very slowly so that the body can adapt and rebuild to changes in pressure. Divers who lay or repair pipes have to spend several weeks on the ocean floor. For example, when using heliox, when diving to 100m, the decompression process takes 4 days, when diving to 300m, decompression takes 10 days.

Divers who have suffered acute decompression sickness after diving often experience symptoms such as hearing loss, reduced sensation in the feet and hands, tremors in the extremities and other neurological disorders. MRI examinations of scuba divers can often reveal small pockets of cell damage in the brain—areas of ischemia due to nerve cell death due to blockage by air bubbles.

The human body reacts to all changes in the environment, including changes in pressure. To prevent the occurrence of irreversible processes, people whose work is associated with work at low or high pressure have developed hygienic requirements for the regime and working conditions, decompression rules, and a list of contraindications for such work.

Well, those who just went to rest on the sea or the ocean, and are also an avid diver, should prepare for diving. This means that a person must be aware of the rules of decompression, know the maximum depth with the mixture that he will breathe, as well as the time during which it will not be harmful for him to descend to the depth.