New Diagnosis for the Bends

If you’re diving in remote areas such as Papua New Guinea, Cocos Island, or even Los Roques in the Caribbean, and think you’re bent, you may be faced with an expensive helicopter evacuation. If you’re on a live-aboard, the boat may have to motor for hours to get to land. Then, you may need to hook up with a pressurized plane to get you to the nearest chamber, hundreds of miles away.

After that lengthy process, evacuated divers sometimes learn after an examination that bends is not their problem. For example, we know a case where a diver’s reaction to the antimalarial drug Lariam led to a costly evacuation to a chamber, all for naught. In another case, a jellyfish sting produced bends-like symptoms.

Now, however, a medical breakthrough by Dr. Michael Bennett (University of New South Wales) may allow doctors to cheaply, easily, and accurately diagnose decompression illness. Bennett has found that after diving, a person can have a few tiny air bubbles in the tear fluid that gathers in the lower eyelid. After a normal dive there will be up to three bubbles, but a bent diver may have between twenty and thirty bubbles in the fluid.

Dr. Bennett counts the number of bubbles, then uses other methods to diagnose the patient and correlate the information. So far his study suggests that those who have the bends definitely have more bubbles than those who have been safely diving or who have not been diving at all.

“ We hope that a remote doctor, suspicious that a patient may have the bends, can do a simple, inexpensive examination of the patient’s tear film. Based on the number of air bubbles, he can decide whether the patient needs to be flown out for further treatment,” Dr. Bennett said.

Dr. Bennett told Undercurrent that the test only requires a slit lamp, which is widely available in ophthalmology clinics and emergency rooms. There are portable instruments available as well. He believes it will take “3-5 more years before it would be in common use.”

( Dr. Michael Bennett, Faculty of Medicine, tel. 9382 3880, or Victoria Collins, UNSW Public Affairs and Development, tel. 9385 3644, e-mail v.collins@unsw.edu.au) .