How to avoid decompression sickness (DCS)

Don't let DCS ruin your dive trip; look after yourself and follow these rules

Here's a good way to not ruin your dive trip: don't get the bends

Decompression sickness (DCS), decompression illness (DCI), the bends, bubble disease – divers often talk about this dreaded condition, one you never ever want to find yourself in. While certain aspects of DCS still baffle many doctors and researchers, you’ll be glad to know there are several things you can do and be mindful of in order to decrease the risk of getting “hit”.

Mind the repetitive dives. A lot of times we want to maximise the number of dives in each dive trip. Do be mindful that this can result in a lot more nitrogen loading which puts you at risk of DCS, especially if the dives are decompression dives. Try to have a longer surface interval in between dives, put in safety stops, and consider a day’s break after a few days of intensive diving.

Watch your rate of ascent from depth. When you fin your way up too quickly, you don’t allow enough bubbles to be offgassed through breathing. So, what you end up with are trapped bubbles in your vessels and tissues, which can cause injury to the body. There also other risks involved, including reverse blocks (ear pain) and pulmonary barotrauma (chest pain).

Keep fit and stay well. As with any other sickness, it’s harder to fall ill when your body is in tip-top condition and ready to face any physically demanding tasks, like fighting unpredictable currents, for instance. In relation to this, what you also need to do is skip dives if you’re feeling unwell, make sure you get enough sleep the night before a day of diving, and do not push it if you’ve been injured before (or if you’re a much older diver).

It’s tempting, but you should resist the urge to go for a quick morning jog by the beach

Avoid exercise pre and post-dive. Especially if it’s strenuous, like running. Raised body temperatures affect blood flow and oxygen use within tissues, resulting in rapid uptake of nitrogen. This is also why you should try not to shower with hot water after a dive.

Don’t go overboard with the alcohol and cigarettes. If you think about things like how alcohol warms up the body and makes you tired, and how smoking deteriorates lung function, you’ll understand how all that nighttime partying might affect your body the next day.

Always remember the no-fly rule. Similar to ascending too fast during a dive, all that pressure brings about undesirable chemical reactions in your body. If possible, allow yourself at least a day to offgas before a flight, and never ever travel to a high altitude after diving (read: no mountain climbing and intense hiking).

When you’re on a dive trip, there’s no such thing as too much water

Hydrate, hydrate, hydrate. We know water is the magic elixir of life. By downing as much of it as you can before a dive, after a dive, and in between dives, you help your body’s process of flushing out nitrogen build-up in the blood and tissues. You can consider isotonic drinks too, but not too much coffee and tea as they can dehydrate.

Drugs and medication matter. No matter what you take, you have to accept that it will definitely alter body functions. Certain medication have side effects that affect things like blood vessels and heart rate, so check with your dive doctor and ask if it’s safe to take the prescribed drugs on a dive trip.

Dr Greg Chan is a senior specialist physician at The Occupational and Diving Medicine Centre, as well as a visiting consultant at the Hyperbaric and Diving Medicine Centre, Singapore General Hospital. He was previously with the Republic of Singapore Navy, where he trained in Canada and Australia and has written two books for divers: Am I Fit to Dive? and Basic Diving Medicine.