DAN was contacted by a diver who had received eight hyperbaric treatments for decompression sickness six weeks ago. He was in good physical shape and an hour after diving he experienced numbness and tingling in his left arm, hand, leg and foot and felt very weak and fatigued. At the end of his treatments all his symptoms had alleviated and four days later he flew home without issue. However, he reported that in the last two weeks he had noticed a return of some of the tingling in his left arm and foot that comes and goes but doesn’t completely go away. He was wondering if this was a normal side effect of decompression illness and whether he should seek further recompression.
According to the DAN’s Report on Diving Accidents and Fatalities, slightly more than 50 percent of all decompression illness cases that received hyperbaric oxygen therapy were successfully treated without residual symptoms. The remaining cases had some neurological symptoms or pain for several days or weeks after hyperbaric therapy was completed. On average, 16 percent of injured divers will still have symptoms for up to three months after they have been treated.
Original symptoms sometimes reappear during this three-month recovery period. Divers have reported the recurrence of symptoms after a series of long days at work, decreasing amounts of sleep, sitting in one position for long periods of time or after drinking too much alcohol. The most often mentioned symptom is numbness and tingling.
In general, recurrence of symptoms can occur, but this is not necessarily normal. It most likely relates to the severity of the original injury. There are three important issues to remember regarding recovering from decompression illness.
In many cases of decompression illness, the response to therapy is related to the time between symptom onset and chamber recompression.
Divers must do everything they can to assure rapid first-aid measures, which includes the use of 100 percent oxygen, and evaluation leading to chamber therapy. It is also important to note that hyperbaric oxygen therapy is a treatment and not always a cure. Divers can suffer mild numbness in a hand or physical impairment that is life-long.
Thirdly, as in any other injury, some recovery time must be expected before an injury can completely heal. Unlike a traumatic injury that is obvious to the eye, injuries caused by gas bubbles are internal.
The tiny bubbles associated with decompression illness, in sufficient quantities, can do more damage than being hit by a car. Never underestimate the potential for a serious injury when symptoms first appear and always seek immediate medical evaluation.
Answer provided by the Divers Alert Network Medical Team.