DAN Medical Q&A

Ask DAN

DAN medical specialists and researchers answer your dive medicine questions

BRUISE-LIKE LINES ON SHOULDERS

Q: About an hour after I completed a single drysuit dive on air, I noticed odd bruise-like lines on both shoulders and behind both knees, but no other symptoms. The uneventful dive was to 20m for 24 minutes in a lake with a water temperate of 10° Celsius. The drysuit was tight around the shoulders, armpits and knees. How would I know if this is skin bends or suit squeeze?

A: When differentiating between drysuit squeeze and the many causes of diving-related skin conditions, we can quickly eliminate most types of marine life injuries simply because the skin is completely covered by the suit. Cutaneous decompression sickness (DCS), or skin bends, is a mild form of DCS. Drysuit squeeze is a type of barotrauma or pressure injury to the skin that is caused by a failure to add air to your drysuit during descent.

While descending, the volume of the air spaces is reduced and trapped in the folds of the suit. The skin tends to be sucked into these folds. Divers will often recall the suit being tight or ill-fitting. The diver may find linear marks or bruises, usually beneath the drysuit’s valves and seams. This condition is usually painless and clears within a few days. To avoid suit squeeze, divers should add just enough gas to the suit during descent and make sure to vent excess gas when ascending.

Cutaneous DCS typically presents as a blotchy, bruiselike rash generally appearing in areas of the body with the most adipose tissue (body fat), such as the abdomen, thighs, buttocks and breasts. The condition usually responds well to surface-level oxygen therapy. DAN has observed, however, that at least 20 percent of divers with suspected skin bends may also experience visual disturbances, weakness, confusion or other neurological symptoms that require recompression treatments. It is important that divers do not overlook these symptoms. DAN always recommends a thorough medical evaluation and appropriate treatment of divers with suspected skin bends.

DIVING AFTER SURGERY

Q: I recently had surgery; when can I dive again?

A: The type or complexity of the surgery directly affects recovery time. The act of diving does not necessitate specific consideration or a protracted recovery time following most uncomplicated surgeries. Exceptions to this general rule involve major organ surgery, i.e., heart, lung, brain, spinal cord and orthopaedic repairs requiring hardware, joint and bone reconstruction. Your surgeon is the best resource to discuss specifics such as the procedure, recovery time and potential complications. If the surgery prompts the need for structured rehabilitation, it can be considered more complex and will most likely indicate a longer recovery period.

When can one safely return to diving after general surgeries? The essential advice is to refrain from diving activities until you are completely healed. The incision(s) should be well healed, and you should be free of pain and recovered from any post-operative complications. When your surgeon releases you for activity without restriction, you can consider a return to diving. Remember that despite complete healing, you may still need time to adequately recover strength, stamina and exercise capacity. Consider a cautious approach to your initial dives. Start in a controlled environment prior to remote travel or dives in rough conditions. The healing process often takes longer than we would like, so please be patient and follow these recommendations to increase your chances for a successful recovery. DANAP.org