UNCERTAINTY AFTER DIVING: Case Report and Recommendations #3

DIAGNOSIS BY EXCLUSION
Diagnosing DCS is generally a process of ruling out other causes. It is imperative that we not discount the possibility of nondiving-related injuries or illnesses just because someone was diving. However, this is not to suggest we should discount the risk of DCS: When a person has been diving, DCS absolutely needs to be considered in the physician’s differential diagnosis.
A 46-year-old male diver on a weeklong dive trip on a liveaboard vessel was doing four or five dives per day. All dives were within recommended recreational no-decompression limits.

 His deepest dive was to 115 feet, which was his first dive on the third day. The next morning, he complained of right shoulder discomfort. Five years earlier he had surgery on that shoulder to repair a torn rotator cuff. Since the surgery five years prior he had done more than 80 dives with no problems, but it was not uncommon for him to experience discomfort in that shoulder with exertion or certain activities. Usually, he could find a position of comfort, apply ice and take ibuprofen to relieve the discomfort, but this time the symptoms were somewhat different and not as easily relieved.

The diver’s companions believed that his symptoms were due to his previous medical history because they had all dived the same profile without any problems. When the diver finally reported his symptoms to the boat crew, they provided him with high-flow oxygen. Based on the fact that the symptoms were different from those the man typically experienced, the captain diverted the ship toward an island with a dive clinic.

After breathing oxygen for approximately 30 minutes, the diver reported some improvement but not much. The ship arrived at the island 30 minutes later, and the diver was taken to the clinic. The physician on duty evaluated him and discovered that his right arm (his dominant arm) was significantly weaker than his left. He diagnosed DCS and treated the diver with a U.S. Navy TT6, which provided measurable improvement.

Because the symptoms did not completely resolve, the doctor treated him again the next day with the shorter U.S. Navy TT5, which brought complete resolution of the symptoms. There is controversy regarding the potential for increased risk of DCS at the site of a previous injury. Little scientific data addressing that issue is available. But controversy notwithstanding, we know that when people with pre-existing musculoskeletal problems choose to dive, diagnostic confusion can result. If you or your dive buddy has such issues, it is imperative for both of you to know what the other person’s usual state looks like. Before diving, discuss any existing pain, movement restrictions, weakness or other information that establishes a clear baseline.

Communicating information about a diver’s normal state can be of great value. Any variation of symptoms from previous experience demands assessment but does not by itself constitute a definitive diagnosis. Divers with these sorts of problems should regularly get a detailed neuromuscular exam by a doctor. After a dive is no time to discover a deficit that may or may not have been there before.

CONCLUSION
The signs and symptoms of DCS are not exclusive to that condition. However, when a person experiences signs or symptoms after diving, DCS is very often presumed to be the diagnosis. This is not all bad, because it encourages divers and dive staff to administer oxygen and ensure the injured diver gets prompt medical care. But it becomes a problem when divers refuse to accept alternative explanations and become fixated on the need for chamber therapy at the expense of other diagnostics and/or treatments that may be delayed.

In addition, the diversion of a nondiving-related emergency from appropriate medical treatment for an unnecessary recompression treatment, especially by air late at night, can introduce additional risks to the patient as well as the aircrew. There are many medical conditions much more serious than DCS for which timely treatment is critical. In the event of symptoms after diving, provide oxygen and get the injured diver to the closest medical facility.

Don’t hesitate to call EMS if the situation is serious, and feel free to call the DAN Emergency Hotline (+1–919– 684–9111) at any time. Tell the doctor that the person was diving, and encourage him or her to contact DAN for consultation. But keep in mind that there are more dangerous ailments than DCS, some of which must be considered first.