Caisson disease: causes, symptoms, risk group, treatment

How does decompression sickness occur?
Consequences of decompression sickness
Severity of decompression sickness
Chronic decompression sickness
Symptoms of divers' disease
Complications of DCS
Diagnostics
Treatment

Caisson disease is a pathological condition in which gas bubbles form in the vessels and tissues of the body.
This occurs due to the rapid decrease in atmospheric pressure. Otherwise, the disease is called decompression sickness (DCS). The name "caisson" comes from the word "caisson". This device was invented in the 19th century for underwater work. The design was a chamber in which a person descended under water. At first, decompression sickness was diagnosed by underwater specialists. Over time, its distribution became wider. Sometimes this condition occurs in pilots who, when changing their flight altitude, are exposed to changes in atmospheric pressure. However, divers are most susceptible to this disease. Fans of scuba diving cannot always cope with the transition from high pressure to normal, which is why they develop “diver’s disease.” According to statistics, up to 4 cases of decompression sickness are recorded per 10 thousand dives. It can be not only acute, but also chronic.

To prevent the disease, you should use high-quality breathing mixtures when diving, avoid a sharp rise from the depths to the surface, observe intervals between dives or flights, and undergo preventive examinations if a person is working underwater.

How does decompression sickness occur?

The main reason for the formation of air bubbles in organs and tissues is a sharp decrease in atmospheric pressure when rising to a height or the surface of the water after a dive. However, there are factors that increase the risk of developing “diver’s disease”:

Age-related changes. With age, it becomes more difficult for the heart and lungs to cope with stress, so decompression sickness is more common in middle-aged and mature people than in young people.
Hypothermia. Cold impairs blood supply to organs and tissues. This is especially true for peripheral vessels. Because of this, the pulmonary vessels receive less blood, which leads to gas retention and the formation of bubbles.
Increased blood viscosity. This condition occurs when dehydration occurs. Blood flow slows down, and blood stagnation occurs in peripheral vessels.
Intoxication. Drinking alcohol before diving is life-threatening. Alcohol provokes dehydration, and when there is alcohol in the blood, air bubbles become larger and can clog the lumen of the vessel.
Overweight. If the body contains a high percentage of adipose tissue, bubbles form faster due to the hydrophobicity of the fat. In addition, fats tend to dissolve inert gases from the breathing mixtures used by divers.
Increased carbon dioxide concentration. This condition is called hypercapnia. It occurs when using poor quality mixtures or when breathing improperly under water. As CO2 concentration increases, more inert gases dissolve in the blood.
Exercise stress. During exercise, blood flow becomes uneven. Gases in the blood dissolve more intensely and air bubbles appear. As a rule, they are very small in size and localized in the joint area. On subsequent dives, decompression sickness may become more severe.

Diagnosis and treatment

If these symptoms appear, you should immediately consult a doctor. In addition to a visual examination, an MRI of the brain and spinal cord may be prescribed.

Make an appointment

Your message has been sent

Thank you for contacting Multidisciplinary Medical!
Your message will be processed shortly and we will contact you to clarify the details.

Be healthy!

Join us on social networks!

Current news, promotions, useful information.

How to find us

OUR ADDRESS

Moscow, st. Shchukinskaya, 2

Shchukinskaya, Streshnevo, Sokol

TELEPHONE

Consequences of decompression sickness

When immersed in water, atmospheric pressure increases. Because of this, the gases of the respiratory mixtures dissolve in the blood of the capillaries of the lung tissues. After ascent, when the pressure returns to normal limits, the opposite phenomenon occurs. Gases dissolved in the blood form bubbles. If a diver ascends quickly, that is, the body does not have time to adapt. If the rate of ascent is not observed, the blood seems to “boil.” At this moment, not only small but also large bubbles are formed. They attract platelets to themselves, increasing in size. These compounds can cause thromboembolism - blockage of the lumen of the vessel.

When a large number of such bubbles with platelets appear in the blood, a gas embolism develops. Circulating through the bloodstream, these compounds can damage the walls of blood vessels, causing hemorrhage.

In addition to blood vessels, bubbles can be found in joint cavities and soft tissues. Gas compounds compress nerve endings, causing pain throughout the body. Foci of necrosis may also occur in the muscles and internal organs, which is also caused by compression.

Text of the book “On the Edge of Possibility: The Science of Survival”

Bubbles in the blood

The cause of decompression sickness was discovered in 1878 by the French scientist Paul Ber. He proved that "writhing" occurs when a diver or caisson worker breathing compressed air rises too quickly to the surface, and then gases dissolved in the blood and tissues are released in the form of bubbles, blocking the blood vessels. The gas inhaled under pressure dissolves in body fluids in a larger volume: for example, for every 10 m of descent, an additional liter of nitrogen is absorbed (as we will see below, this process is not fast). As long as the gas is present in liquids and tissues in a dissolved state, excess does not create problems. The difficulty arises from the insufficient rate of removal of dissolved gas during decompression. If a diver rises to the surface slowly, the excess gas dissolved in the blood is expelled by the lungs when exhaling and does not pose a danger, but if the ascent occurs quickly, the lungs simply do not have time to remove the gas out, so the tissues and blood become oversaturated and at some point the gas breaks out of the solution in the form of bubbles{13} 13
One of the first to describe this phenomenon was Robert Boyle, who in 1670 observed the formation of an air bubble in the eye of a viper during decompression.

[Close]. This phenomenon is familiar to anyone who has opened a bottle of sparkling water (or champagne): as soon as the pressure disappears, chains of bubbles rush out. If the cap is pulled off abruptly (fast decompression), the effect will be more impressive than if the cap is gently unscrewed and the gas is released slowly. However, if carbon dioxide is dissolved in carbonated water and champagne, then in divers breathing compressed air, bubbles in the blood are formed primarily by nitrogen, since the content of carbon dioxide is extremely low, and oxygen is quickly consumed by the tissues.

Why do sperm whales not suffer from decompression sickness?
Many marine mammals are capable of diving to depths inaccessible to humans. A dead sperm whale was once found at a depth of 1134 m, where it had caught its lower jaw on a transatlantic cable. Elephant seals are even more skilled divers, the record level they have reached is 1570 m, at this depth the pressure is 150 times higher than the pressure on the surface. This is far beyond human capabilities. In addition, elephant seals can dive repeatedly without experiencing any ill effects. In fact, the elephant seal would be more accurately called a “floater” rather than a diver, since it spends 90% of its time underwater. One of the elephants spent no more than six minutes on the surface during 40 days of observation. How do sperm whales and elephant seals avoid decompression sickness?
The thing is that marine mammals have developed a way to reduce the amount of nitrogen dissolved in the tissues of the body. Unlike humans, elephant seals and sperm whales exhale before diving. In this way, they limit the supply of air that they take with them, so somewhere at a depth of 50 m the alveoli are already completely compressed and no additional gases penetrate into the bloodstream. Pressure at depth forces the sperm whale's lungs themselves to completely compress, displacing all the air into the upper respiratory tract, which is reinforced by round cartilage discs and is less compressible. Blood flow to the lungs is also significantly reduced. Thus, during a dive, the gas practically does not enter the blood from the lungs, and the residual amount of nitrogen dissolves in body fluids, so when ascending, the formation of bubbles in the blood of the mammal does not threaten.

The formation of bubbles in the blood is fraught with serious consequences. Once formed, they continue to grow due to new portions of gas. As a result, they grow to such a size that they clog the thinnest blood vessels and prevent blood flow to the tissues, causing a lack of oxygen and nutrients. As a result, the cells die. In addition, air bubbles can activate blood cells that respond to air flow, such as platelets, which are involved in the formation of blood clots. Finally, the formation of bubbles within tissues can lead to deformation or rupture of tissue cells and impair their function.

Divers have developed a rich vocabulary that describes the symptoms of bubbles in various tissues. “Choke” – interruptions in breathing when large bubbles get stuck in the capillaries of the lungs, reducing the surface area necessary for gas exchange and causing sensations similar to asphyxia. “Wobble” occurs due to bubbles in the vestibular apparatus, which is responsible for balance. Bubbles in the knee and shoulder joints (the places most vulnerable to decompression sickness) lead to “writhing.” Being in the spinal cord, they lead either to numbness of the limbs or to paralysis, and in the most serious cases they can provoke degeneration of nerve fibers. Their appearance in the brain leads to speech and vision disorders, sometimes irreparable.

There is one curious story (possibly fictitious) about how, when digging one of the first tunnels under the Thames, the management decided to mark the passage to the middle mark with a dinner party directly in the tunnel. Since construction had not yet been completed, compressed air was supplied to the tunnel, and the guests had to dine “under pressure.” Much to their disappointment, the champagne did not shoot or “play” when opened, since the pressure in the bottle turned out to be the same as in the tunnel. And yet they drank champagne. The champagne that was drunk began to sparkle only later, when the leaders and guests came to the surface...

You need to climb slowly

Soon the caisson workers themselves discovered that increased atmospheric pressure compared to their working conditions relieved unpleasant symptoms. This gave Sir Ernest Moir the idea of a recompression chamber to treat decompression sickness. A similar camera was first used around 1890 in the construction of the Blackwall Tunnel under the Thames and the East River Tunnel in New York, where it proved its worth. However, the injured worker had to spend more than one hour in the cell to recover. It was clear that efforts should be directed, first of all, to the prevention and prevention of the disease. Thanks to the work of Paul Beer, the solution became obvious: the diver or caisson worker must ascend (or decompress) slowly enough to allow the lungs time to expel the gas dissolved in the blood. The most difficult thing remained - determining a safe ascent speed. By 1906 the problem had become so acute that the British Navy turned to Professor John Scott Haldane of Oxford University, a physiologist already known for his research on respiration (see Chapter 1), for help.

Together with Lieutenant G. Damant and Professor A. Boycott, Haldane conducted a series of experiments at the Lister Institute in London with a large steel chamber in which the pressure could be easily adjusted. During experiments on goats, it turned out that with a sharp decompression from 6 to about 2.6 atmospheres, nothing bad happens to the animal. However, if the pressure was reduced by the same amount, but from 4.4 to 1 atmosphere (i.e., to sea level), things took a different turn. Only 20% of the animals managed in this case to avoid decompression sickness, which sometimes took the most severe forms, including death. After some trial and error, the researchers found that they could quickly reduce the absolute difference in pressure by up to half, but then they had to reduce the difference as slowly as possible. Thus, the maximum diving depth that did not require decompression was identified - 10 m (pressure of 2 atmospheres). As has long been customary among physiologists, the researchers then conducted the test on themselves, fortunately, without consequences. The final stages of the experiment were carried out at sea off the Isle of Bute, off the western coast of Scotland, from the HMS Spanker. Haldane took the whole family to the sea and allowed his 13-year-old son Jack, who later also became interested in studying respiratory processes, to dive to a depth of 12 m {14} 14

As J. B. S. Haldane later wrote, it was still entertainment. The sleeves of the wetsuit ended with tight rubber cuffs that did not allow water to pass through. But the suit turned out to be too big for the boy, so water seeped inside and filled the suit up to the neck. Fortunately, the air pumped into the helmet did not allow the water to rise higher, but John was thoroughly chilled.

[Close].

Haldane was aware that the rate of dissolution of nitrogen in different tissues varied. Fat cells, for example, have a greater storage capacity, while brain cells store less nitrogen (this, in turn, means that women and obese people take longer to decompress than the average man). In addition, the rate of nitrogen accumulation depends on the rate of blood flow to tissues, so tissues with lower blood supply accumulate nitrogen more slowly. Thus, it takes more than five hours to completely saturate the body with nitrogen. During decompression, nitrogen dissolved in fluids and tissues must be eliminated through the bloodstream. The safe rate of its removal depends on the storage capacity and the rate of blood supply to various tissues, that is, simply put, the longer the gas accumulates, the longer it takes to be eliminated. It follows that the optimal situation for a diver is a quick dive, a limited time at depth, then a slow, gradual ascent to the surface.

The rapid dive recommended by Haldane and his colleagues was contrary to accepted practice, but it was quite justified from a physiological point of view: the less time a person spends at depth, the less gas will have time to dissolve in the tissues. During the first, fast stage of the ascent, the diver must overcome half the depth - this, as experiments have shown, is completely safe. The ascent should then proceed smoothly, with stops for a certain time at a certain depth to ensure gradual decompression. The meaning of this phasing is that the gas always increases in volume the same way, regardless of whether the pressure drops from eight atmospheres to four or from two to one (recall that the product of pressure and volume is a constant value, therefore, when the pressure is halved the volume will double). The research gave divers the benefit of a quick and unimpeded ascent to half depth, thereby allowing more time for decompression during further ascents. As Haldane himself noted, “the traditional method of recovery is ‹…› unduly slow at the beginning and dangerously accelerated towards the end.”

By 1908, Haldane and his colleagues had provided the Navy with detailed decompression tables outlining how long a diver should stay at a certain depth during a gradual ascent, depending on the depth and duration of the dive. Thanks to these tables, the number of cases of decompression sickness decreased sharply; they were observed only when the diver, for some reason, neglected the recommendations and ascended faster than prescribed. Not everyone immediately realized the importance of Haldane's research. As he himself said ten years later: “It is a great pity that in some countries it is not possible to introduce staged decompression due to the rigid rules of old-fashioned ascent either gradually or slowly at the beginning and accelerating as one approaches the surface and atmospheric pressure.” Fortunately, the results of his research spoke for themselves, and now the Haldane method is widely used. Nevertheless, tragedies still occur - as a rule, in case of neglect of recommendations. Among the most notorious accidents is the death of Chris and Chrissy Rous, quite experienced divers who died from decompression sickness in 1992 while examining a sunken German submarine.

It is interesting to compare how much time it took for caisson and tunnel workers to decompress in the past and how much time Haldane and his colleagues spend on decompression. The caisson workers, exposed to three times the atmospheric pressure (i.e. 3 bar), rose to the surface in ten minutes or less. Haldane recommended that after three hours of work, decompression should be at least an hour and a half. It is not surprising that so many caisson workers suffered from cramps.

In addition, divers are not recommended to remain in the air for some time after diving, since the pressure in an airplane is less than at sea level (see Chapter 1), and a further decrease in pressure can also cause the formation of bubbles in the blood. After a single dive, the diver must refrain from flying for 12 hours, and even longer after multiple dives or dives requiring gradual decompression. Marine recreation enthusiasts who are not familiar with the problems of decompression can develop decompression sickness if, after swimming with scuba gear in the morning, they fly home in the afternoon. Even military pilots flying unpressurized fighter jets risk succumbing to decompression sickness if they climb too quickly from sea level.

Scuba diving and decompression sickness

Divers without special equipment who immediately dive to great depths do not suffer from decompression sickness, since they do not stay at depth for long and the amount of nitrogen that is dangerous for ascent does not have time to dissolve in body fluids. Repeated deep dives are a completely different matter, as military doctor P. Pauleu, who served in the Danish Navy, found out from his own experience. In the early 1960s, he completed about 60 two-minute dives at intervals of one or two minutes in a submarine evacuation training tank (depth - 20 m). About half an hour after the final dive, he felt a sharp pain in his left thigh. At first he decided not to pay attention to her, but two hours later he began to experience severe chest pain, fog in his eyes, shortness of breath, and his right arm became paralyzed. In a state of painful shock, he was discovered by a colleague, who immediately placed him in a compression chamber, lowering the pressure in it to six atmospheres. The symptoms quickly passed. The subsequent decompression took over 19 hours, but, fortunately, Pauleu made a full recovery and subsequently described everything that happened to him.

Pearl divers on the Tuamotu Islands in the Pacific Ocean also often fall into a state similar to what Dr. Pauleu suffered. In their language it is called "tarawana" and translates as "crazy fall", and symptoms range from visual disturbances to loss of consciousness. Sometimes divers experience paralysis or even death (after all, unlike Dr. Pauleu, they do not have a decompression chamber). As one of the guests of the archipelago noted: “On the shore of any island, the largest group of buildings will most likely turn out to be a cemetery for dead divers.” Taravana is a common disease and is greatly feared. In one day alone, 47 of the 235 divers developed symptoms, some very severely, as six were paralyzed and two died. Fortunately, such extreme manifestations do not occur every day, but the incidence rate is still very high.

Although the etiology of taravana remained a mystery for many years, the work of Pauleu and his followers suggests that it is a type of decompression sickness. Tuamotu divers do not spare themselves, making two-minute dives to depths of up to 40 m (pressure - 5 bar). They make from 6 to 14 dives per hour with a scanty interval of 4–8 minutes. During this time, nitrogen, dissolved in tissues during a dive, does not have time to be eliminated from the body and accumulates with each new dive, therefore causing decompression sickness during ascent (taravana has never been observed at depth, only on the surface). It should be feared primarily by those who make repeated dives at short intervals. It should be noted that on the neighboring island of Mangareva, where the taravan has not even been heard of, tradition tells the diver to spend at least ten minutes on the surface between dives.

At the entrance to the water

Decompression sickness is not the only difficulty a diver faces. Even simply immersing the body in water up to the neck already causes physiological changes. When you stand on the seashore, the blood tends to your feet under the influence of gravity. If you are submerged in water up to your neck, the external pressure of the water will cause about half a liter of blood to rush up to the chest, filling the large veins and the right atrium, and increasing the volume of blood flow. The stretching of the atrium wall signals two hormones that affect the kidneys' water absorption and urine production. This is why we often want to go to the toilet after diving into water.

Ama - Japanese divers
The most famous divers in the world are the Japanese ama, who collect seafood (clams, sea slugs, octopus, starfish and algae) from the seabed. In Japan, unlike Western cuisine, all this goes into food. In addition, the Ama collect pearl shells called akoya-gai, which are used to grow artificial pearls. The profession of ama divers has existed for more than 2,000 years. This traditionally female activity is immortalized in prints by artists of the ukiyo-e school, depicting beautiful topless girls diving for the most valuable shells of the abalone shellfish. The engravings, however, somewhat embellish the reality, since ama work until they are 50 years old. And their work is not all sugar. This is how Sei-Syonagon, a court lady of the Japanese Empress Sadako, describes it: “The sea frightens even the prosperous. What horror must the unfortunate divers feel who have to plunge into the abyss for the sake of a piece of bread. It’s best not to even think about what will happen if the cord tying a diver’s waist breaks. While the women are underwater, the men sit in their boats and sing songs so as not to get bored, watching the crimson cord floating on the surface. An amazing sight is the complete indifference of men to the danger threatening women. Before rising to the surface, the diver pulls the cord, and the men, with haste that I understand, pull her out of the water. And now the diver is already clinging to the side of the boat, convulsively gasping for air. Even an outside observer cannot help but cry at the sight of this picture, and there is hardly a person who dreams of such work.”

Girls watch divers on Enoshima. From a triptych painted by the great ukiyo-e artist Utamaro around 1789.

The description of Sei-Syonagon is still relevant today, although a lot of water has passed under the bridge since then.
There were once thousands of ama in Japan (the 1921 census, for example, recorded 13,000), but their numbers have declined sharply in recent years. By 1963 it had dropped to 6,000, and now there are barely more than a thousand. Most modern ama are already aged, since few young people are attracted to such exhausting work. In addition, many types of shellfish are now grown artificially. Apparently, the ama profession will soon die out, surviving as a sad echo only in the names of villages like Amamati.

It so happens that among the Ama there are two varieties - katido and funado. Katido are young girls, students who dive without assistants to a depth of 5–7 m and spend about 15 seconds at the bottom. Although a katido can make about 60 dives per hour, it is not at risk of decompression sickness due to the shallow diving depth. The most experienced and skillful divers are funados, who dive to much greater depths - on average about 20 m. As can be seen from the Sei-Syonagon description, each funado has an assistant in the boat. After taking a series of rapid breaths to fill its lungs with air, the funado dives vertically to the bottom with a heavy load in its hands, squeezing its legs tightly for better streamlining. At the bottom, she releases the weight and begins to collect her prey in a small wicker basket. Before surfacing, she pulls a cord attached to the weight, and an assistant pulls the diver out by a rope tied around her waist. Each dive lasts about a minute, and half of that time is spent at depth. Between dives, the funado also rests for about a minute in the water, at the side of the boat. An experienced diver makes about 50 dives in the morning, then the same number in the afternoon, however, like a katido, after a series of dives she needs rest.
Caisson disease is not common among the Ama, but they suffer from ear diseases much more often than representatives of “land” professions. According to a 1965 study, 60% of funados experience hearing loss after the age of fifty. Other common ailments include ringing in the ears and ruptured eardrums.
Physiologically, women are better suited for the role of divers - they can hold their breath longer and freeze less in the water, but it is unlikely that only for these reasons all amas are exclusively female.

Even by simply dipping our face into water, we thereby cause a physiological reaction in the body - the heartbeat slows down. This phenomenon is known as the diving reflex, and although not very developed in humans, it is extremely important for marine mammals such as seals, as we will see below. You can verify the existence of this reflex yourself by immersing your face in a bowl of cold water and asking one of your friends to count your pulse and compare it with normal. However, this experiment does not always work, since nervousness (or excitement) causes the release of adrenaline, which increases the heart rate.

When we surface, the body is deprived of water support, and the blood is again redistributed from the chest to the legs. This must be taken into account. History knows many cases when drowning people rescued by helicopter developed collapse after rising from the water: a person stays afloat quite actively, and after being lifted into the helicopter he suddenly experiences cardiac arrest. Physiology came to the rescue here too, proving that when immersed in water, blood flows out of the legs and they cool more than the upper part of the body. Until recently, people were rescued from the water in an upright position by threading a rescue belt under their arms. As a result, when pulled out of the water, the blood instantly rushed to the legs, where it immediately cooled and, returning to the heart, caused it to stop. Lifting in a horizontal position helps to avoid this, using a second belt that wraps around your legs. In this case, blood redistribution does not occur. It is also important to keep the person lying down until the limbs warm up evenly. Since the British Water Rescue Service adopted this method, the number of cases of cardiac arrest after water rescue has dropped sharply.

Severity of decompression sickness

Depending on the manifestation of symptoms, DCS is divided into four degrees of severity:

Easy. With a mild degree of pathology, the patient experiences pain in the muscles and joints, which is associated with pressure on the nerve endings of air bubbles. Due to blockage of superficial vessels and sweat glands, the skin begins to itch and becomes oilier.
Average. Moderate pathology causes deterioration in coordination of movements, blurred vision, and disruption of the gastrointestinal tract. This is due to the accumulation of gases in the vessels of the mesentery and intestines.
Heavy. The main symptom of the pathology is damage to the spinal cord due to compression of the nervous tissue. In some cases, the brain is involved in the pathological process. This is manifested by disturbances in the functioning of the heart and respiratory system.
Lethal. Decompression sickness can be fatal if large bubbles clog vital vessels. The patient's blood supply to the lung tissue stops and acute heart failure develops.

Even with moderate severity of the pathology, acute “diver’s disease” can lead to severe damage to organs and systems. If left untreated, these conditions are life-threatening.

History and description of the disease

DCS is a disease caused by a sharp decrease in the pressure of gases inhaled by a person - nitrogen, oxygen, hydrogen. At the same time, dissolved in human blood, these gases begin to be released in the form of bubbles, which block normal blood supply and destroy the walls of blood vessels and cells. In a severe stage, this disease can lead to paralysis or even death. This condition often develops in those who work in conditions of high atmospheric pressure during the transition from it to normal pressure without taking proper precautions. This transition is called decompression, which gives the disease its name.

Similar decompression is experienced by workers constructing bridges, ports, foundations for equipment, digging underwater tunnels, as well as miners developing new deposits and divers, both professionals and amateurs of underwater sports. All this work is carried out under compressed air in special caisson chambers or in special wetsuits with an air supply system. The pressure in them specifically increases with immersion in order to balance the growing pressure of the water column or water-saturated soil above the chamber. Staying in caissons, like scuba diving, consists of three stages:

Compression (period of increased pressure);
Working in a caisson (being under consistently high pressure);
Decompression (a period of pressure reduction during ascent).

It is when the first and third stages are carried out incorrectly that decompression sickness occurs.

A potential risk group is recreational divers. Moreover, news reports often talk about how military doctors have to “pump out” reckless divers.

For the first time, humanity encountered this disease after the invention of the air pump and caisson chamber in 1841. Then workers began to use similar cameras when constructing tunnels under rivers and securing bridge supports in wet soil. They began to complain of joint pain, numbness of the limbs and paralysis after the chamber was returned to normal pressure of 1 atmosphere. These symptoms are currently called DCS type 1.

Symptoms of divers' disease

Beginners are not always able to recognize the symptoms of decompression sickness, because they increase gradually. The exception is the most severe degrees of the disease, in which a person feels unwell from the first minutes after surfacing. For most people, the first signs of pathology appear within an hour and gradually increase over five to six hours. Delayed decompression sickness occurs most rarely. It appears 1-2 days after the dive.

Symptoms depend on the degree of the disease. Patients with a mild form of the pathology experience pain in the back and joints. Usually the shoulders and elbows hurt the most, and the pain intensifies with movement. A rash or a “marbled” pattern may appear on the skin. The changes are accompanied by itching. Some people have enlarged lymph nodes.

If the degree of damage is more severe, the patient feels dizzy and has a headache, hearing deteriorates, sweating appears, and the skin turns pale. A person cannot engage in usual activities due to spots and fog before the eyes. Abdominal pain also appears, which is accompanied by nausea and vomiting, loose stools.

Patients with severe decompression sickness experience loss of sensation in the lower body, spasms, and problems with urination and defecation. If the brain is involved in the pathological process, headaches appear, a temporary speech disorder develops, and hearing deteriorates.

Patients with severe DCS require urgent treatment due to impaired respiratory function and cardiac function. The disease manifests itself as weakness and shortness of breath, chest pain, and decreased blood pressure. In the absence of medical care, acute oxygen deficiency develops, pulmonary edema may also develop, and the risk of myocardial infarction increases. Breathing becomes shallow, the skin turns pale and becomes blue.

In the fatal form of the disease, death occurs due to severe heart failure, which is caused by impaired circulation in the lungs or inhibition of the respiratory center located in the brain.

If the disease is chronic, the joints and bones are the first to suffer. This leads to the development of deforming arthrosis. Submariners may develop heart problems. Experts have different opinions regarding cardiac pathologies associated with decompression sickness. Many are sure that regular stay at depth contributes to the earlier development of atherosclerosis and myodegeneration of the heart.

Prevention

Prevention of decompression sickness involves careful adherence to safety precautions and rules for working in compressed air conditions. Employees are hired only after a medical examination, which must then be regular. People working at depth should lead a healthy lifestyle, not drink alcohol in excess, and stop smoking.

After suffering from decompression sickness, workers are removed from deep-sea work in the following cases:

severe course of the disease;
the presence of residual effects;
decompression sickness occurred more than once.

Complications of DCS

Most often, patients suffer from chronic Meniere's syndrome, in which pathology affects the middle ear. The person experiences dizziness and hearing gradually deteriorates. Another possible disorder is aeropathic myelosis, which is a lesion of bone marrow cells.

With moderate and severe variants of the disease, all kinds of cardiac pathologies of an inflammatory and degenerative nature occur. Among the most common are endocarditis and myocarditis, cardiosclerosis. Pneumonia may develop from the respiratory system. The most common neurological manifestations of the disease are paresis, muscle paralysis, and loss of sensitivity.

Consequences

For each person, the consequences of decompression sickness can be expressed differently. They depend on the severity and form of the disease. Timely medical care also plays an important role, since, as already mentioned, if it is not provided on time, death can occur. Among other things, the following consequences of the disease can be identified:

cardiosclerosis;
heart failure;
inflammation of the optic nerve;
respiratory failure;
disorders in the gastrointestinal tract;
osteoarthritis, etc.

Diagnostics

If there are signs of DCS, you should contact a traumatologist. Depending on the form of the disease and its manifestations, treatment is also carried out by cardiologists and neurologists. The doctor examines the patient and collects anamnesis. Hardware procedures include ECG, X-ray, ultrasound of internal organs, CT and MRI.

Without fail, the doctor evaluates the functioning of the heart and lungs, the condition of the spinal cord and brain. When examined on an X-ray, gas bubbles can be seen in the tissues and joints, which confirms decompression sickness.

Pathogenesis of development

To find an explanation for how decompression sickness develops, it is necessary to turn to physics, namely Henry’s law. It says that gases dissolve in a liquid with the intensity with which the liquid itself exerts pressure on these gases. That is, the higher the pressure, the better the gases dissolve. The faster the pressure drops, the faster the gases in the blood will form bubbles. Moreover, they will appear not only in the blood, but also in other fluids of the human body. Therefore, with decompression sickness, the spinal cord, brain, joints and lymphatic system are affected.

Gas bubbles that appeared during a sharp pressure drop will unite and block the vessels, as well as destroy cells or squeeze them. The result of such a violation is blood clots, which can either rupture the vessel or cause the death of its tissue. With the blood flow, gases travel throughout the body and can cause disruption in the functioning of almost any organ.

So, the reasons that can lead to decompression sickness:

Rising to the surface from depth too quickly.
Immersion in cold water.
Severe fatigue or being under stress.
Excess body weight.
The age of the person.
Air travel after diving to depth.

The following reasons will lead to the development of pathology during immersion in a caisson chamber:

A person's stay under water for too long.
Diving to a depth of more than 40 meters. Under such conditions, the pressure increases by 4 atmospheres or more.

Treatment

For minor manifestations of the disease, the patient remains at home or in the hospital under the supervision of a doctor. In moderate and severe cases, it is necessary to carry out recompression, which takes place in a pressure chamber and allows the patient’s condition to normalize.

Recompression consists of several stages. First, the pressure rises, as if the person is again at depth. A person stays in such conditions for half an hour or more. After the condition has normalized, the pressure is gradually reduced, simulating a rise to the surface of the water. Oxygen is also supplied, which will displace nitrogen from the blood. In some cases, the procedure must be repeated.

If the patient develops complications, then symptomatic treatment and physical therapy are prescribed. According to statistics, 80% of people with “diver’s disease” return to their previous lives without health consequences if treated in a timely manner.

4.Treatment

Great importance is attached to the time factor: even with the apparent mildness of the symptoms, a patient with signs of decompression sickness should be taken to a medical facility as soon as possible.

The first-line treatment is usually hyperbaric oxygen therapy. General restorative, analgesic, anti-inflammatory, neuroprotective and other drugs are used symptomatically. Up to 80% of cases can be stopped without any special consequences.

However, due to the high risk of severe complications (both in the immediate and long-term period of decompression sickness), detailed methods of prevention have been developed - in the form of instructions for stepwise descent and ascent, monitoring the condition, monitoring over time, etc. These requirements must be followed strictly .