7 Easy Ways to Identify Decompression Sickness Symptoms

Feeling the onset of decompression sickness symptoms is one of those scenarios that terrify most divers. Most new and experienced divers alike have heard of decompression sickness, but not all of us really understand it or know how to properly identify its symptoms. We all can agree scuba diving is an incredible experience but, occasionally an accident or emergency may occur, and knowing how to properly manage it can be the difference between a great anecdote or a fatality.

What is decompression sickness?

Decompression illness, also known as DCI, is the condition that results from a reduction in the pressure surrounding the body. It actually includes two ailments, decompression sickness (DCS) and arterial gas embolism (AGE). It is believed that DCS is caused by bubbles growing in tissue and causing local damage, while AGE is caused by bubbles entering the lungs, traveling through the arteries and causing tissue damage from a distance by blocking blood flow in small vessels.

Aviators, astronauts, people who work in compressed-air and scuba divers are all at risk for decompression illness. Activities that can cause decompression illness in divers include deep or long dives, diving in cold water, strenuous activity in deep water and ascending too quickly. Other factors thought to increase the risk of DCI are obesity, dehydration, scuba diving while pregnant, strenuous exercise immediately after surfacing and lung disease. Some people seem to be more at risk than others, which is why some divers seem to get DCI more easily even though the circumstances of the dive are the same.

Why is decompression sickness called the bends?

Decompression sickness is also known as divers’ diseaseaerobullosis, generalized barotraumacaisson disease and our personal favorite, “the bends”. The name the bends came about during the construction of the Brooklyn Bridge in New York City when a person with decompression sickness assumed a bent-over posture due to joint pain.

How to avoid decompression sickness

Taking the proper precautions is the best way to avoid the bends. For an amateur diver who is not going on a decompression dive, the most important thing to do is to stay well within the no-decompression limits or NDLs, which is the limit for the amount of time a diver can stay at a certain depth. This will be termined by your dive tables and/or your dive computer. Having a properly functioning diving equipment is crucial for a safe dive, which is why you must make sure it is in tip-top condition, especially if you have used scuba gear. In addition, control your ascent, in other words, ascend slowly, little by little. Last but not least, perform at least one 3-minute safety stop during a dive. It’s also important to stay hydratedDo not drink alcohol before diving and avoid flying or driving to a higher elevation within 24 hours after a dive.

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Following these guidelines should cause the nitrogen and other inert gasses that are absorbed into the body’s tissues to return to the bloodstream and eventually be eliminated out through the lungs. However, if the guidelines are not followed, the absorbed gasses will expand and form bubbles in our tissues and bloodstream, which is what causes decompression sickness.

Symptoms of decompression sickness

The most common symptoms of depression sickness include local joint pain and arm and leg symptoms. There are two types of DCS, type 1 and type 2. Type 1 generally includes aches and skin symptoms while type 2 is considered to be more serious and can affect the brain, inner ear, and lungs.

Symptoms vary widely and may appear before a dive is finished or may not appear for at least an hour after diving. In fact, symptoms may not appear for up to 48 hours after a dive. Sometimes you can do everything right and still develop decompression sickness. Always be alert for signs of discomfort for up to 48 hours after a dive. It is important that if you notice any of the following symptoms, don’t panic and seek medical help immediately.

1.  Bone and muscle symptoms       

Localized deep pain, ranging from mild to excruciating, mostly in large joints including the elbows, shoulders, hip, wrists, knees, and ankles. Sometimes it can feel like a dull ache, but rarely a sharp pain. Moving the joint aggravates the pain but the pain may be reduced by bending the joint to find a more comfortable position.

2.  Skin symptoms     

Itching, usually around the ears, face, neck, arms, and upper torso and/or the feeling of insects crawling on the skin, which may appear marbled around the shoulders, upper chest, and abdomen. There may be swelling of the skin, accompanied by small skin depressions.

3.  Brain symptoms   

There may be a feeling tingling or numbness, increased sensitivity, confusion or memory loss, visual abnormalities, unexplained mood or behavior changes, seizures or unconsciousness.

4.  Spinal cord symptoms     

Weakness or paralysis in the legs is possible, as well as incontinence. There may also be a tightening feeling around the abdomen and/or chest.

5.  Whole-body symptoms

These include headache, tiredness, aches and just overall feeling ill.

6.  Inner ear symptoms

A loss of balance, dizziness, vertigo, nausea, vomiting or hearing loss.

7.  Lung symptoms    

A dry persistent cough and/or burning chest pain under the sternum which is made worse by breathing and shortness of breath.

How to handle an emergency while scuba diving

When a diving emergency occurs, it’s important to know how to handle it. First, just like in an airplane, make sure you are ok before helping someone else. You won’t be able to assist anyone effectively if you are not safe yourself. Second, have a planned escape route ready and make sure you know it by heart so if there is an emergency you will be able to get out of the water and get help as quickly as possible.

In the case of a low air emergency, slow down and relax, which will help you to breathe more slowly and will conserve gas. Ascend a bit, which reduces gas use and will help you to get further before you have to surface. Don’t risk running out of gas underwater. Always surface with a few hundred psi remaining in your tank.

To learn how to prepare for any and all emergency situations, become a rescue diver with Aquaworld’s PADI Rescue Diver Certification in beautiful CancunMexico, where colorful coral reefs and abundant marine life abound. If you are open water certified, have 40 registered dives and can provide proof of current CPR, first aid and oxygen provider certification, you can take the Rescue Diver Certification course. The certification will teach you how to assure not only your own safety, but the safety of those you are diving with, to prevent diving emergencies and how to manage an emergency should one occur. The course consists of four days of training, including an academic session, a confined water session, and two 2-tank open water diving sessions.

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Decompression sickness treatment

Decompression sickness is a treatable illness but requires very special treatment, recompression, the opposite of decompression. Recompression is achieved in a special piece of equipment called a hyperbaric chamber, a pressurized room or tube. The main function of recompression is to compress the gas bubbles causing the symptoms, allowing the bubbles to be re-absorbed. The body’s tissues need enough oxygen to function and when tissue is injured, it requires even more oxygen to survive. In a hyperbaric chamber, the air pressure is increased to three times higher than normal air pressure so that the lungs can take in more oxygen than would be possible through normal breathing. Breathing higher levels of oxygen speeds up the removal of gas bubbles from the body.

Self-treatment with oxygen after surfacing, or with oxygen-rich mixtures while still diving is not recommended and could be fatal, while hyperbaric oxygen therapy is generally safe, and complications are rare.

Hyperbaric oxygen therapy is typically performed as an outpatient procedure and doesn’t require hospitalization. The increased air pressure will create a temporary feeling of fullness in the ears, like what happens on an airplane or at high elevations and can be relieved by yawning or swallowing. The treatment lasts approximately two hours, but more than one session may be needed.

Decompression sickness is something to be aware of, but not something to worry about, as it does not occur during or after the vast majority of dives. Scuba diving is a popular, enjoyable, safe activity, as long as you have the proper training and follow the correct procedures. The good news is that if you do develop decompression sickness, it is a treatable condition. In fact, most people recover and continue to dive.