Decompression Sickness - Symptoms & Treatment
Decompression sickness (DCS) occurs when the body is subjected to a sudden reduction in surrounding pressure. Because air under high pressure is compressed, each breath taken at depth contains many more molecules than a breath taken at the surface.Water is heavier than air, so when you dive, small changes in depth cause large changes in pressure underwater. Boyle's law states that the product of the multiplication of pressure and volume remains a constant. As outside pressure decreases during ascent from a dive or when leaving a caisson, the accumulated nitrogen that cannot be exhaled immediately forms bubbles in the blood and tissues. In other cases, serious injury does occur; when this happens, the quicker treatment begins, the better the chance for a full recovery. If the pressure is reduced too quickly, however, the nitrogen comes out of solution and forms bubbles in the tissues and bloodstream. Bubbles forming in or near joints are the presumed cause of the joint pain of a classical "bend." The risk of developing decompression sickness increases with increasing pressure (that is, the depth of the dive) and with the length of time spent in a pressurized environment. Flying immediately after diving (such as at the end of a vacation) exposes a person to an even lower atmospheric pressure, making decompression sickness slightly more likely. Decompression sickness may affect a variety of organs and can range from mild to severe.
Decompression sickness is a disorder in which nitrogen dissolved in the blood and tissues by high pressure forms bubbles as pressure decreases. It is, in fact, an old-fashioned term used originally to describe the appearance of workers returning from 'caissons' during the construction of bridges in the 19th century. Following their shifts, some men would return to the surface suffering joint pain that made it difficult for them to stand straight. The connection between the workers' return to the surface and their symptoms led to the introduction of surface based recompression chambers to treat the afflicted. Carbon dioxide, a waste product of metabolism, is excreted through the lungs very efficiently and therefore does not present a problem when decompressing. These bubbles may expand and injure tissue, or they may block blood vessels in many organs either directly or by triggering small blood clots. This blood vessel blockage causes pain and a variety of other symptoms. Other risk factors include rapid ascent, fatigue, exertion, dehydration, cold water, obesity, and older age. Numbness, paralysis and disorders of higher cerebral function may result. If great amounts of decompression are missed and large numbers of bubbles enter the venous bloodstream, congestive symptoms in the lung and circulatory shock can then occur.
Causes of Decompression Sickness
The common Causes of Decompression Sickness :
- Scuba divers who rise too quickly after diving in deep water.
- Those who go quickly from a lower to a higher altitude.
- Inadequate surface intervals (ie, failure to decrease accumulated nitrogen) .
- Other causes of obstruction include congestion caused by allergies or mucosal polyps, excessively aggressive Valsalva attempts, or previous facial injuries.
- Those who exit from a high pressure or hyperbaric chamber.
- DCS is caused by the formation of gas bubbles in the blood and tissues.
Symptoms of Decompression Sickness
Some common Symptoms of Decompression Sickness :
- Skin swelling
- Chest pain , especially when taking a deep breath
- Shortness of breath or trouble breathing
- Abdominal distress
- Numbness or tingling in the arms or legs
- A blotchy skin rash
Treatment of Decompression Sickness
- If you experience symptoms of DCS, it is extremely important to get treatment immediately. In severe cases, delayed treatment may be fatal.
- Treatment should be given even if initial symptoms are mild or disappear. Proper treatment administered quickly should cure all symptoms of DCS.
- If you have DCS I, breathing 100% oxygen from a mask may be sufficient treatment. You should also be monitored carefully for the initiation of any other symptoms.