Crisis on a liveaboard

DIVERS ALERT NETWORK: ASIA-PACIFIC Divers Alert Network, widely known as DAN, is an international non-profit medical and research organisation dedicated to the safety and health of divers. WWW.DANAP.ORG

A DAN member experiences severe decompression illness, requiring six recompression treatments, while on an overseas liveaboard trip with his dive club.

The Diver: A 60-year-old male in good general health with no significant medical history. The Diver’s Experience: Advanced Nitrox certified. The Trip: Liveaboard diving holiday in Coron, Philippines. The Dives: Multiple air dives over three consecutive days with safety stops completed on each dive.

ONSET OF SYMPTOMS

After exiting the water the diver took a warm shower, and within ten minutes he noted progressive numbness and weakness of both legs. The symptoms commenced in the lower left leg and progressed toward the left abdomen and chest, with gradual pain and increasing difficulty walking.

The diver also experienced gradual progression of a sensation of fullness in the abdomen, bloating of the stomach, and pain when urinating.

On the boat, oxygen was immediately provided by nonrebreather mask and administered throughout the journey to Coron. The diver was also given oral analgesics to help with the pain, although they provided little relief.

When the call was made to the DAN Emergency Hotline, the liveaboard was on its way to Coron. However, due to the severity of the diver’s condition, DAN wanted the diver to receive a higher level of care, and action was taken to transport the diver via air ambulance to the chamber in Manila.

TREATMENT

The diver arrived at the chamber on a stretcher; he was conscious and coherent with stable vital signs. The key complaints were weakness and numbness in both lower extremities, abdominal fullness and discomfort, as well as moderate lumbar pain. Due to difficulty urinating, the diver had a catheter. Because his symptoms were so severe, the diver received six recompression treatments over six days.

After each of the first two treatments (U.S. Navy Table 6 treatments — 4h 45 minutes each, to a depth of 18m), the diver advised that the pain in his lower back was bearable and the numbness was diminishing. He was able to stand independently, but he was wobbly, weak and uncomfortable.

With the symptoms persisting, the diver underwent a further three shorter US Navy Table 5 Treatments (at 2h 16 minutes each, to a depth of 18m), followed by a Table 9 treatment (also at 2h 16 minutes, but to a reduced depth of approximately 14m) to deal with the residual symptoms.

At the end of all treatments, the diver’s catheter was removed, he had improved balance, and he was better able to walk unassisted. He was advised to not fly for an additional 72 hours and was required to undergo a diving medical examination prior to returning to diving.

RECOVERY

The diver continued to improve slowly after returning home. He was tested for a PFO (Patent Foramen Ovale – a mild, congenital hole in his heart), and the test was positive. The diver elected to have the PFO closed. The procedure took place approximately nine months following the DCI incident. Four months after the procedure the diver was given clearance to dive on the proviso he dived conservatively.

ANALYSIS

This member was fortunate that the liveaboard he was diving from had plenty of oxygen and crew that understood that he needed oxygen to manage his condition while the boat was travelling to Coron. This contributed to his eventual recovery.

The call to DAN was made shortly after the onset of symptoms, and this enabled DAN’s assistance team to organise the evacuation to Manila and advise the chamber team so they would be ready to receive the diver.

All divers should remember that DCI can occur on what some would consider to be relatively benign dive profiles. Even though his profiles were well within the limits of his computer, he became seriously ill. Further steps should be taken — particularly in remote areas — to reduce the risk of DCI, such as using a conservative setting on your computer.

Through testing, it was found that this member had a hole in his heart (PFO). We are finding that PFOs are not uncommon — one in every four people has one. In this case the hole allowed bubbles to cross the heart, bypassing the filtering by the lungs, and serious symptoms resulted.

Having a PFO does not mean the end of a diving career. It does mean that the diver needs to have a serious discussion with a physician trained in dive medicine to determine what options are available and how to best manage the increased risk of DCI. In this case, the decision was made to have the hole repaired and to dive more conservatively to reduce bubble loading in the body. n

DAN EMERGENCY HOTLINE

In the event of a diving incident, we encourage all divers to call the DAN EMERGENCY Hotline promptly for advice: • Within Australia: 1800 088 200 • Outside Australia: +1 919 684 9111 • Within Indonesia: 21 5085 8719