Decompression illness

Marine mammals are not above the physical principles and processes that lead to bubble formation in tissues following decompression. Scientists once thought that diving marine mammals were immune from decompression sickness, but beached whales have been found to have gas bubbles in their tissues—a sign of the bends. In any case, how some marine mammals and turtles can repeatedly dive as deep and as long as they do has perplexed scientists for a very long time.

Because DCS isn’t the most straightforward diving injury, myths and misconceptions about it tend to arise. DAN is committed to continually educating divers about it, and we’ve decided to clarify a few of the most common misconceptions about it to ensure that all divers are better able to recognize DCS, respond to it and get the treatment they need in time.

A recent big-data study performed by a DAN Europe research team used modern statistical analysis techniques to dig into a sample of nearly 40,000 open-circuit recreation dives and look for patterns and clues about DCS risk factors in real-world cases. Some of what they’ve found confirms our previous knowledge and opens entirely new avenues for research into the factors that contribute to DCS risk. Here’s what we’ve learned.

Diving on a blistery morning can be fun, but shivering your way through an hour of decompression can put you on a fast track to the local chamber. It is up to you to make sure that you are adequately prepared for your dive, and for the aftermath. It is easy to end up cold on a dive through no fault of your own, but knowing the signs and symptoms of hypothermia before you dive will help you know when you might be pushing things just a little too far.

Being tired or achy after a long dive, unplanned exertion at depth or a change in decompression planning is often not considered very seriously; if you do not have symptoms, the prevailing thinking is to not worry about it. Despite the way divers have operated for decades, researchers at the forefront of decompression research are pushing hard for greater consideration of the factors that contribute to DCS risk—factors, which combined, create a total picture of our risk.

Whether you have the skills and training to care for a diver yourself or you want to be prepared to help until a more experienced caregiver is available, learn the basics of assessing post-dive symptoms.

Articles like this one are no replacement for training, but they are a good way to refresh or build your awareness of the importance of emergency-response skills.

Almost all experts in dive medicine agree that divers should ascend slowly following dives, whether they’re recreational, working or technical. The reality is that very little direct evidence exists about what ascent rate is safest. Most of the recommendations come from observational studies of bubble grade found using Doppler ultrasound or are based on anecdotal or theoretical concerns.

For three decades the researchers at DAN have monitored, tracked and analyzed diving incidents and fatalities worldwide. One of the best sources of this incident data is you, the diver. When you self-report an injury or incident that you experienced or witnessed via the DAN Incident Reporting System, you offer a valuable look at real world diving incidents and injuries.