Decompression illness

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.

IPE is the abnormal leakage of fluid from the bloodstream into the alveoli, the microscopic air sacs in the lungs. Symptoms include shortness of breath, coughing up bloody sputum, and respiratory distress. Leakage into the alveoli results in fluid buildup in the lungs, and interrupts gas exchange, similar to drowning. It is important to note that fluid resulting from IPE comes from within the body, rather than from inhalation of surrounding water.

Technical diving, and technical mixed-gas diving in particular, presents divers with increased risks and a unique set of hazards. Mixed-gas divers need to manage complex equipment, multiple breathing gases, and mitigate their risk of narcosis and the hazards caused by increased gas density by replacing some, or all, of the nitrogen in their breathing gas with helium. This use of high-content helium gases requires special considerations for gas switching and an adjustment of ascent rates and decompression time, and it can pose additional risks.

In isolated locations without the industry or population required to support medical facilities equipped to deal with dive related emergencies, in-water recompression (IWR) becomes an attractive prospect for dealing with decompression sickness, and a hotly debated issue.