During the 1960s several abalone fishermen on the west coast near Port Lincoln were developing decompression sickness (“the bends”). They commonly dived to 50 feet (approximately 10-15 metres), though sometimes much deeper, to harvest the shellfish, while breathing compressed air pumped down from a tender boat. Hurried and repeated trips to the surface with the catch during such dives were the cause of “the bends”: if surfacing occurred too quickly, nitrogen came out of solution into the blood and tissues, causing severe pain (“the bends”). Paralysis, convulsions, and death could occur in severe conditions.
Surfacing after a compressed air dive should be done slowly with rest periods (“stops”) at prescribed depths according to established “tables”. These allowed excess nitrogen dissolved in the blood to be eliminated from the compressed air they had been breathing.
Some victims tried analgesics and other homespun remedies but effective treatment required compression in oxygen (hyperbaric therapy) in a special chamber. The affected divers were flown to the Royal Adelaide Hosptial, the flight was conducted in a non-pressurised aircraft, causing another problem because the reduced cabin pressure at altitude allowed any bubbles to expand and thus worsening symptoms.
The RAH chamber was about one metre wide and 2 metres long, into which the patient was slid on a stretcher and then pressurised. Rapid access to the patient in an emergency by an attendant was not possible.
There were increasing demands on the South Australian State Government to install a bigger chamber in the RAH, but the cost was a disincentive. Divers continued to present with decompression sickness and in 1986 Dr. Gilligan and three Intensive Care Unit specialist nurses trained in hyperbaric medicine with the Royal Australian Navy, School of Underwater Medicine, and the Prince of Wales Hospital, New South Wales, where a complete hyperbaric operating suite and services had been established in the 1950s.
National Safety Council of Australia (Victoria Division) offered the Royal Adelaide Hospital hire of a large multiperson hyperbaric chamber and staff to operate it, as the NSCA at that time was keen to foster research into diving and decompression incidents and a public hospital was an ideal location. Purpose built hyperbaric chambers were large enough to hold an attendant as well as a patient and were ideally the size of a small room.
The offer was accepted by RAH administration and the chamber, mounted on a large truck, was used by the RAH into the early 1990′s until funding was obtained to install a permanent multiperson chamber.
Dr Des Gorman, ex RAN Commander, was appointed Director of Hyperbaric Medicine. The department became a major centre for hyperbaric medicine and an emergency call centre for divers with decompression problems throughout South-East Asia and the Pacific. This service was called the “Divers Emergency Service” and it became a national consultation centre for diving emergencies, in parallel with one in Sydney. Later, Melbourne and Brisbane followed suit. In addition, the project with NSCA resulted in the development of transportable hyperbaric chambers to be taken to the site to enable earlier imitation of recompression for the injured divers, though the more widespread availability of fast, pressurised aircraft reduced the need except in very remote areas such as Pacific Islands.
Hyperbaric oxygen can be beneficial in the treatment of decompression illness, arterial gas embolism, problem wound healing, and carbon monoxide exposure, to name a few.