Man’s primordial love the sea surface

Man’s primordial love the sea surface, which was probably started because of not-so-idyllic search for food and later for material goods (corals, pearls, etc.), Now takes on a whole new dimension. The advancement of technology, diving has become a popular and relatively easily accessible activity. Will you think about diving as a sport, recreation, fishing, military, archaeological or research activities, depends only and only to you. You, and only up to you and will you be one of those who during the warm summer months to yield to the temptation challenges diving (usually associated with a well-thought-out advertising campaigns in various “diving”) and join the lovers of the sea depths. Despite the man’s constant striving to explore something new, diving is not a harmless activity and requires the right decision. Before the diving practiced exclusively healthy, physically well prepared and adult individuals who have undergone special, not very easy diving training. Today, they think that diving can be enjoyed by almost everyone, regardless of health status, physical fitness and age (the age limit is increasingly being lowered), and everything is working “family enjoying” the magic of the deep sea. Before embarking on the adventure of diving, the most important is the well informed and critically evaluate yourself and your abilities, because we, unfortunately, fresh-come a growing number of deaths of divers (especially amateurs) on the Adriatic. It should be reminded on so-called. factor “3 N” that represents the leading cause of death of divers, which make ignorance, inexperience and lack of discipline.

» The reason I love the sea I cannot explain — it’s physical. When you dive you begin to feel like an angel. It’s a liberation of your weight «

Jacques Cousteau

Physiology of diving

Dive diver in the sea increases the pressure around him. How lungs would not collapsed, the air must be supplied also under high pressure, and blood in the lungs exposed to extraordinarily high pressures in the alveoli of the lungs (pulmonary bubbles), which is called hiperbarizam. The column of seawater high around 9.7 m putting pressure on the bottom as well as the air above the surface, so the diver at this depth and exposed to the air pressure and the resulting pressure due to the weight of sea water. The following is an important effect of the depth of compression (compression) gas to smaller volume (Boyle’s law). Therefore, all cavities in the body of a diver filled with air (including the lungs) can sometimes so to reduce the resulting severe damage.

Possible health complications in diving

During the dive there may be two types of complications: injury (barotrauma) and decompression sickness.

Injury (barotrauma)

When sudden immersion depth, if a diver does not inhale the additional quantity of air, all body cavities filled with air will suffer damage in the sense of being crushed. They may then arise: the eardrum to rupture, bleeding in the middle and / or inner ear, severe pain and bleeding from the sinuses, is also not unusual damage to eyes and face (if it loses air from the mask). During rapid ascent if the diver does not exhaled air from the lungs, due to changes in the pressures of the gases in the alveoli may arise air embolism blood vessels and lungs pneumothorax (presence of free air in the pleural space), a not uncommon injury of the abdominal viscera.

Exposure and poisoning gases

The diver breathes air is exposed to nitrogen (N), oxygen (O2) and carbon dioxide (CO2). Nitrogen (N) makes 4/5 of the air and at sea level has no effect on body functions. Exposed to high pressure, causing varying degrees of narcosis because it dissolves in fats nerve cells (membranes and other lipid structures), and this causes a reduction in their excitability. Symptoms are similar to the symptoms of alcohol poisoning (initially gaiety and euphoria, followed by reduction of prudence, and later lethargy, lack of coordination and a complete inability), which is caused by nitrogen narcosis often called “depth of inebriation” or “deep ecstasy”. The high pressure affects the transport of oxygen (O2) in blood, being markedly increases the amount of oxygen dissolved in the blood, which can cause oxygen toxicity, which is manifested by nausea, muscle twitching, dizziness, visual disturbances, irritability and disorientation. The very depth does not increase the pressure of carbon dioxide in the alveoli or increasing its production as long as the diver breathes as much carbon dioxide as it is created. However, carbon dioxide can be collected in the air “dead space” of diving equipment (mask), where it diver re-inhalation, which can cause depression center for breathing and may develop severe respiratory acidosis, and different degrees of lethargy and narcosis. As a substitute for nitrogen is often used helium (He) as it has a small atomic density, which reduces airway resistance, weight, and dissolves more quickly removed from the body fluid. The narcotic effect is 4-5 times lower than nitrogen. However, at greater depths can apply effects in terms of tremor (tremor), dizziness and loss of coordination. Nitrogen is more appropriate than helium when the diver remains on the bottom to 1 hour and at depths of less than 30 m.

Decompression sickness

When the diver inhales a long time under high air pressure, increases the amount of nitrogen that dissolves in body fluids. This nitrogen relations in all body tissues, and that does not participate in metabolic processes, it is necessary to remove the breathing. Once the diver is totally fed up with nitrogen, a few hours to a pressure of nitrogen in the tissue equal to the nitrogen pressure in the pulmonary alveoli. The speed at which the diver should emerge on the surface depends on the depth to which lowered and the time that is spent there. There are special tables which have to comply with all divers in the ascent. If the diver keep in the sea long enough to be in the body dissolve large amounts of nitrogen and spring back to the sea surface, in body fluids generate substantial amounts of nitrogen bubbles. Depending on the quantities generated bubbles, there are milder or more severe damage to the body, or decompression or bends. Name bends originates from the French word for chest (caisse), because the disease is described in workers in caissons filled with compressed air, who worked under water (to excavation of the foundations for bridges, etc.). The symptoms of decompression sickness are: fatigue, pain in the arms, legs and joints and / or generalized aches and pains, weakness, disorientation, loss of concentration, skin manifestations (cutis marmorata) with itching, dizziness, paralysis, shortness of breath, collapse and unconsciousness. The most difficult problems arise due to the formation of bubbles in the nervous system, in which may arise permanent paralysis and brain damage. Bubbles which dissolve in the lung capillaries may cause pulmonary edema. Symptoms occur a few minutes to an hour after the sudden decompression, but it can and after several hours.

Prevention of decompression sickness

The best way to avoid decompression sickness: dive inside the curve of security, a high-quality, properly serviced and tested equipment and, based on experience and knowledge, critically assess their current skills for diving (pay attention to hypothermia, “bad day”, suspected acute disease , unforeseen problems etc.). In addition, all the while diving should be carefully “listen” as our body “speak”.

Treatment of decompression sickness

It is conducted in specially designed device – hyperbaric chamber (hyperbaric chamber), which allows room at an increased pressure, which also represents the simulator diving (just as there is no water). Treatment of injured divers for decompression carried out specially trained medical team, according to specific protocols. The treatment in the hyperbaric chamber is the only effective treatment, and the results are better as a diver before delivered. Unfortunately, the condition of rapid feeding of injured divers sometimes can not be satisfied because our coast there are relatively few hyperbaric chamber for treatment of divers (Pula, Krk, Split, Dubrovnik).

Recommendations for safe diving

Children are not recommended diving for many reasons (lack of adequate child equipment, less muscle mass, incomplete growth of bones and lungs; diver must be independent, in children there is still no need of intellectual and emotional maturity; there is currently no proven safe treatment protocols children- divers because all treatment protocols safe only for adults)!

Never dive at least 12 hours after the flight and 24 hours before flying!

Never dive alone!

Respect your limits and mood!

Dive only with proper and serviced equipment!

Strictly follow the instructions diving instructor!

Author: Ivana Bočina, dr. med.

From: Narodni Zdravstveni List