Caisson disease in divers and divers
Caisson disease is an occupational pathology that predominantly affects divers and divers. In medical dictionaries, this disorder is called decompression sickness (DCS).
- Decompression sickness - what is it?
- Options for the course of decompression sickness
- Development pathogenesis
- How to detect and treat decompression sickness?
Decompression sickness - what is it?
Caisson disease is a violation of the normal blood supply to organs and tissues, provoked by a sharp drop in the pressure of gases that a person breathes (oxygen, nitrogen, hydrogen). The gases that are present in the blood in a dissolved form are converted into bubbles. They interfere with normal blood flow, contribute to the destruction of the vascular wall and tissue cells. If the disease has a severe course, then the person may remain disabled or even die. Often this condition develops in people who are in conditions of high atmospheric pressure. It manifests itself at a time when a person returns to an environment with normal atmospheric pressure, but does not observe the necessary safety measures.
At risk are people who are engaged in the construction of ports, bridges, underwater tunnels, that is, all divers. Moreover, not only professionals can suffer, but also amateurs to dive to depth. A person in a special caisson chamber or in a diving suit is exposed to high atmospheric pressure. It is increased specifically to balance the water pressure on the suit or camera.
Diving takes place in 3 stages:
- Compression stage during which the pressure increases.
- The stage of performing the necessary work, when a person is in conditions of high atmospheric pressure.
- Decompression stage, when the pressure decreases and the person rises to the surface.
If violations were committed during the first or third stage, the diver may develop decompression sickness.
People became aware of the disease in 1841, when the first air-pumped caisson chambers were invented. They were used to build bridges and underwater tunnels. The people who were in these cells complained of joint pain, numbness of the arms and legs, and paralysis. Now all these symptoms have been thoroughly studied, they are classified as signs that characterize decompression sickness of the first type.
Options for the course of decompression sickness
Modern medicine distinguishes 3 types of decompression sickness.
They differ depending on which organs were damaged during diving:
- The first type of decompression sickness. This type of disease is life threatening, but it is not great. A person will experience joint pain, his lymphatic system, skin and muscles will suffer. In addition to pain in the shoulder and elbow joints, the victim will have increased back and muscle pain. They will pick up intensity as they try to move. The nature of the pain is boring. Also, there are skin rashes of the type of spots, which are very itchy, the lymph nodes increase in size.
The second type of decompression sickness is a threat to human life. The pathological process will involve the brain and spinal cord, circulatory and respiratory systems. A person experiences urinary disorders, he has severe headaches, tinnitus. If the disease is severe, the victim may become deaf and blind, and a coma is not excluded. Choking is also a symptom of type II decompression sickness, but it rarely happens. However, shortness of breath and chest pain cannot be ignored, as this can be fatal. Another danger of a person's prolonged stay in conditions of high atmospheric pressure is the development of aseptic necrosis of bone tissue.
After decompression, decompression sickness develops in half of the people. Most often, the disease has a severe course. The first signs of a disturbance in the body appear 6 hours after rising to the surface. Although there is evidence of the development of decompression sickness even 24 hours after the dive.
To find an explanation for how decompression sickness develops, it is necessary to turn to physics, namely to Henry's law. It says that gases dissolve in a liquid with such an 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 and brain, joints and lymphatic system suffer.
Gas bubbles that appear during a sharp drop in pressure will coalesce and close the vessels, as well as destroy cells or pinch them. The result of such a violation is blood clots, which can either rupture the vessel or cause the death of its tissues. With the flow of blood, gases travel throughout the body and can cause disruption in the work of almost any organ.
So, the reasons that can lead to decompression sickness:
- Too fast ascent to the surface from depth.
- Immersion in cold water.
- Extreme tiredness or being under stress.
- The age of the person.
- Flight after diving.
The following reasons will lead to the development of pathology when immersed in a caisson chamber:
- A person's stay under water for too long.
- Diving to a depth of over 40 meters. Under such conditions, the pressure rises by 4 atmospheres or more.
How to detect and treat decompression sickness?
In order for the doctor to have the opportunity to make the correct diagnosis, he needs to report in as much detail as possible about the symptoms that the person is experiencing. The doctor will prescribe the patient an MRI or CT scan of the brain and spinal cord, which will allow to establish characteristic abnormalities in them. Dysbaric osteonecrosis is also a sign of decompression sickness, which can be detected by imaging.
In 80% of cases, the disease can be completely cured. However, for this, therapy should be prescribed as early as possible.
For recompression, special equipment is used, which delivers large amounts of oxygen into the victim's bloodstream. This allows excess nitrogen bubbles to be removed from the blood. Oxygen enters the human body under high pressure. If it is not possible to conduct therapy immediately after lifting from a depth, then the patient must be taken to a medical facility as soon as possible.
Follow-up therapy will be aimed at eliminating the symptoms of decompression sickness. The patient is prescribed pain relievers, drugs to relieve inflammation and to strengthen the immune system.
So that a person does not develop decompression sickness, it is necessary to correctly calculate the decompression mode, slowly ascend from the depth. This allows the body to adapt and not react sharply to pressure drops. Modern cameras are equipped with computer technology that minimizes the risks of decompression sickness. However, the computer is not able to assess the individual characteristics of the organism of each person. In addition, it happens that people themselves simply ignore all the rules for safe diving and ascent to the surface.
It should be borne in mind that decompression sickness can develop not only in divers who dive very deeply. In a mild degree, the pathology can occur even in divers. Therefore, it is so important to know the symptoms of the disease and to avoid the causes leading to its occurrence.
Video: what is decompression sickness?
The author of the article: Shutov Maxim Evgenievich | Hematologist
Education: In 2013 he graduated from the Kursk State Medical University and received a diploma "General Medicine". After 2 years, completed residency in the specialty "Oncology". In 2016 completed postgraduate studies at the National Medical and Surgical Center named after N. I. Pirogov.