What Is Decompression Illness?
Decompression illness is a disorder in which gases like nitrogen dissolve in blood and form bubbles due to the sudden decrease in surrounding pressure. It is also known as generalized barotrauma or bends. It mainly occurs in scuba divers, during extra-vehicular activity from spacecraft, flying in an unpressurized aircraft, etc.
When scuba divers dive into the ocean, they absorb extra oxygen and nitrogen. The pressure is different inside the sea compared to land. When they are in the ocean, the body will use oxygen, and nitrogen will remain in the body. When the divers move to the water's surface, they come in contact with the atmospheric pressure of land. If this transition is rapid, there will not be enough time for the nitrogen to escape from the body.
As a result, they will separate out of the blood and form bubbles in the blood and tissues. This can cause severe joint and bone pains. They can also block the normal blood flow by forming small blood clots. Vertigo, numbness, chest pain, etc., are some of the symptoms that can accompany this condition. Treatment involves recompression therapy or treatment with oxygen.
What Are the Two Types of Decompression Illness?
There are two types of decompression illness – type 1 and type 2.
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Type 1 Decompression Illness – It is a less severe form. It is the musculoskeletal form that mainly affects joints and is also known as bends. It mainly affects the joints of the arms, legs, muscles, or back. It can also affect the skin and lymphatic system. Pain is sharp and worsens on moving. In this, the pain may be mild initially and may worsen gradually. It is not a life-threatening condition.
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Type 2 Decompression Illness – It is a severe form and causes neurological symptoms. The spinal cord can be affected. At times, it may lead to paralysis.
What Are the Causes and Risk Factors of Decompression Illness?
The main causes of decompression illness include;
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Increased depth of dives.
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Increased duration of dives.
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Frequent diving with no sufficient gap between dives.
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Rapid ascent – In most cases, rapid ascent may be due to panic.
The above factors do not cause decompression illness in all individuals. It depends on other factors. The main risk factors that can cause decompression include;
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Dehydration.
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Coldwater.
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Certain heart defects, for example, patent foramen ovale.
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Flying after diving.
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Fatigue.
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Older age.
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Failure to take appropriate safety measures while diving.
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Prior history of decompression illness.
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Smoking.
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Lack of sleep before diving.
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Drinking alcohol before diving.
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Rough sea conditions.
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High-fat meal.
What Are the Symptoms of Decompression Illness?
The main symptoms of decompression illness include;
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Fatigue.
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Loss of appetite.
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Feeling of illness.
These are the first symptoms that can appear in decompression illness. The symptoms begin slowly, and it can take some time to reach maximum effect. In some cases, symptoms start appearing within one hour, whereas in some cases, symptoms may take six hours to appear.
In type 1 decompression illness, the main symptoms include:
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Severe pain in joints, arms, legs, etc.
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Itching.
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Rashes.
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Swelling of arm and abdomen.
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Extreme fatigue.
In type 2 decompression illness, the main symptoms include:
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Numbness.
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Weakness and tingling of arms or legs or maybe both, which later progress to irreversible paralysis.
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Inability to urinate or to control urination.
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Confusion.
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Trouble speaking.
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Double vision.
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Vertigo.
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Hearing loss.
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Chest pain.
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Difficulty in breathing.
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Shock and death in severe cases.
How to Diagnose Decompression Illness?
The diagnosis of decompression illness involves a clinical examination and patient history. The symptoms and history are evaluated for the proper diagnosis. Computed tomography (CT) and magnetic resonance imaging (MRI) is also recommended to assess the brain and spinal cord condition. In some cases, a chest X-ray is also recommended in identifying pneumothorax. If the affected individual already has an untreated pneumothorax, then hyperbaric oxygen (HBO) treatment is contradicted.
How to Treat Decompression Illness?
The treatment for decompression illness should be started immediately once the diagnosis is made (even before the results of CT or MRI). The primary treatment given in decompression illness is hyperbaric oxygen therapy. It is also known as recompression therapy. It is the primary treatment in all types of decompression illness, even if the symptoms appear some days later. If HBO therapy is not available immediately, initial treatment should be started with 100 % oxygen. The diving community will have these emergency oxygen devices.
The HBO therapy helps increase the concentration of oxygen, decrease the concentration of nitrogen, and decrease the size of gas bubbles. Fluid administration can be done in affected individuals to minimize dehydration. If the patient has neurological symptoms, treatment should focus on maintaining the airway, breathing, and circulation (ABC).
The patient should be given HBO therapy as soon as possible. If recompression therapy is given at the earliest, recovery is faster. If the patient has to be transferred for further medical help, transportation should be done in pressurized aircraft if it is aeromedical transport. If an unpressurized aircraft like a helicopter is used, flight altitude should be less. If divers have only mild symptoms like itching, skin rashes, and fatigue, there is no need for recompression therapy. But they have to be kept under observation.
What Are the Complications of Decompression Illness?
Dysbaric osteonecrosis and permanent neurologic complications can be late effects of decompression illness. Dysbaric osteonecrosis is the destruction of bone tissue, especially in the shoulder area, leading to severe pain and disability. Permanent neurologic complication involves permanent or partial paralysis.
How to Prevent Decompression Illness?
Decompression illness can be easily prevented by;
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Limiting the depth and duration of dive and decreasing the speed of ascent. Proper instructions should be given to individuals before taking the dive.
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The individuals must be adequately hydrated, well-rested, and enough safety precautions have to be taken.
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Individuals must avoid flying for at least 24 hours or taking a hot bath immediately after diving.
Conclusion:
Decompression illness is a condition that can be easily avoided if people are aware of the safety precautions that have to be followed before taking a dive in the ocean. Measures should be taken to educate people about the safety precautions so that everyone can have a wonderful experience of exploring marine life.
