The Causes of "The Bends" Decompression Illness

Nitrogen - a normally inert gas in the causes issues while under pressure. As the Diver descends the ambient pressure increases. The diver is now breathing gases at high equivalent partial pressures than on the surface. As the pressure increases, more nitrogen dissolves into the tissues. The longer a diver remains at depth, the deeper a diver goes or ascending too rapidly - the more nitrogen dissolves for any specific depth. Unlike the oxygen in the air tank a diver uses to swim underwater, the nitrogen gas

Like a can of soda these bubbles can be released very fast - or with caution - they can be released slowly.

A diver returning to the surface is similar to opening the bottle of soda. As a diver swims to the surface, the ambient pressure decreases. The nitrogen, which has dissolved in tissues, will want to dissipate as it will try to equalize to ambient pressure. The body can only cope with a certain amount of nitrogen. Beyond which damage and/or injury can occur.


If a diver surfaces too fast, the excess nitrogen may be released into the body as gas bubbles. Depending on which organs are involved, these bubbles produce the symptoms of decompression sickness.  As this can happen in any tissue of the body the symptoms vary wildly between individuals and even within the same patient. For these reasons the symptoms are often overlooked, ignored or rationalized away.

Major factors in the cause of Decompression  Illness - "Getting Bent"

  • Dehydration - Without the proper fluids, the body has enough difficulty processing it's own waste - let alone nitrogen bubbles.
  • Well-being - Without a fully functional immune system, the addition of un-natural bubbles can overwhelm a system
  • Alcohol - IT already dehydrates, but also adds poor decision making
  • Exertion - The increase (or decrease) in metabolism can cause excessive amounts of bubbles to enter the system
  • Rapid changes in elevation (airplanes) - Just like a rapid ascent from a dive, a rapid ascent in a plane can casue bubble release

The risk of decompression illness is directly related to the depth of the dive, the amount of time under pressure, and the rate of ascent. Dive tables and Dive computers attempt to provide guidelines as to what depth and which dive times have the least risk for the development of decompression sickness.