As mentioned in the last blog and talkcast, the way to avoid is to limit the factors that predispose divers to DCS. Some factors are unavoidable. So make the others of more importance. Physiologists still don't understand all factors that may predispose an individual to DCS, but the list is a start to what they do know. No matter what you do, DIVE CONSERVATIVELY. NEVER DIVE TO THE LIMITS OF A DIVE TABLE OR COMPUTER. They may be wrong for you at that time.
Following is a short list of these factors and a brief explanation.
FAT TISSUE
Fat tissue is slow tissue, holding a high amount of dissolved nitrogen. A lot of fat tissue increases the nitrogen retained in the body. Divers that have a higher fat ratio to lean muscle are more likely to have more nitrogen after a dive and therefore have a slightly higher risk of DCS.
AGE
The circulatory and respiratory system works less efficiently in the older population. This interferes with gas exchange. Remain fit by reducing the fat content and exercising regularly to counter this factor.
DEHYDRATION
Dehydration reduces the quanity (volume) of blood available for gas exchange, slowing nitrogen removal from the body. Comsumption of diuretics (caffine), profuse perspiration, and even the dry scuba air tend to dehydrate the diver. During metabolism of alcohol uses a great deal of water. Thus a diver with a hangover is more likely to be partially dehydrated. To do: Make sure you drink plenty of water before, during and after the dive. More than you normally would do.
INJURIES AND ILLNESS
Any condition that affects normal circulation can potentially affect nitrogen elimination. Healed conditions may reduce local circulation difficulties. Also any illness can produce a general reduction in circulation. Make sure you do not dive if you have any injuries or illnesses. It is simply not worth it. Better to heal and dive a different day.
ALCOHOL
Alcohol consumed before or after a dive alters physiology, we all know that but in favor of DCS. Alcohol tends to accelerate circulation and can cause tissues to carry higher amounts of nitrogen. After a dive, alcohol dilates capillaries, possibly increasing the rate of nitrogen release and bubble formation.
CARBON DIOXIDE
Elevated carbon dioxide from skip breathing or improper breathing may interfere with the gas transport by the circulatory system by dilating the capillaries, and again increasing nitrogen uptake.
COLD WATER
During a cold dive, inadequate exposure protection in moderately warm water, changes normal circulation, as the body trys to stay warm. At start of dive, circulation carries nitrogen to all parts of the body, but as heat is conserved, this reduces circulation to the hands and feet. There is less blood to carry away dissolved nitrogen during ascent.
HEAVY EXERCISE
Exercise while diving increases blood circulation, carrying nitrogen to all parts of the body faster than normal. After resting, circulation returns to normal, and so there is no corresponding circulation to accelerate nitrogen elimination.
ALTITUDE AND FLYING AFTER A DIVE
Reduced atmosphere pressure at altitude increases the pressure gradient between tissue and the ambient pressures and can possibly cause larger bubble formation. Once DCS occurs returning to sea level does not usually correct the problem
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