Under pressure

Dr David Wilkinson, OAM, works in a field not many of his colleagues recognise or respect …

DR David Wilkinson was awarded an Order of Australia Medal in the Queen’s Birthday Honours, something of which he’s rightly proud.

What makes him most proud, however, is that he was given the award “for services to hyperbaric medicine”.

“I am very happy to wave that flag,” he tells the MJA.

Dr Wilkinson graduated from Flinders University in 1986, and earned his Fellowship to the Australia and New Zealand College of Anaesthetists in 1997. These days he plies his trade as an anaesthetist at Royal Adelaide Hospital (RAH) one day a week, but it is hyperbaric medicine that grabbed his attention almost 20 years ago. Today, Dr David Wilkinson is director of the RAH’s Hyperbaric Medicine Unit.

“I was in the intensive care unit of the Royal Adelaide when I was a registrar,” he says. “Dr John Williamson, who was the previous director of the hyperbaric unit came in to pick up a patient, and I asked him if I could come and have a look.

“As soon as I walked into the room and saw that hyperbaric chamber I was completely fascinated by it. There was an element of frontier medicine about it. It took my fancy.”

Most people associate hyperbaric medicine with scuba diving, decompression chambers and “the bends”, and indeed diving medicine is a big part of Dr Wilkinson’s working life, but certainly not all.

“In hyperbaric medicine we treat a variety of medical conditions, some acute and some chronic,” he says.

“For non-healing wounds — diabetic foot for instance — hyperbaric medicine can reduce the risk of amputations.

“It can be used to treat radiation tissue injury after treatment for cancer. It does reverse damage to normal tissue without any consequences to the cancer cells. That’s increasingly being demonstrated in randomised controlled trials.”

Acute conditions like gas gangrene and necrotising fasciitis also benefit from time spent in the steel chamber breathing 100% oxygen at 2 or 3 atmospheres’ pressure.

Part of the fascination with the specialty is the diverse populations he gets to treat, says Dr Wilkinson.

“On the one hand there are the older patients with chronic conditions like diabetes, and on the other there are the divers, who tend to be younger and healthier. The two populations don’t mix.”

The other fascination is just how hyperbaric treatment works.

“The underlying mechanism — there are very specific actions at work and it can’t be just oxygen,” Dr Wilkinson says. “The combination of oxygen plus pressure works at a supraphysiological level to bring about changes in cell function.”

Evidence is important to Dr Wilkinson and hyperbaric practitioners in general because the specialty hasn’t always enjoyed the respect of other colleagues.

“I guess there’s always been a degree of mystery about it,” he says. “That leads to suspicion, but hopefully my colleagues will listen and not presume.”

Dr Wilkinson is currently working on his PhD through the University of Adelaide focusing on hyperbaric treatment’s effect on glucose control in diabetes.

“We’ve known for 20 years that when you put a diabetic in a hyperbaric chamber there is a tendency for their blood sugar levels to drop,” he says.

“But we stopped at that point.

“I’m interested in the mystery of what’s going on and I’m working with endocrinologists. We’ve identified an increase in insulin sensitivity — a key starting point for type 2 diabetes — with hyperbaric oxygen exposure.

“That seems worthy of further investigation. It’s very much a mystery and as far as I know, nobody else is doing it.”

A big part of Dr Wilkinson’s life is running the RAH’s Divers Emergency Service 24-hour telephone hotline, something he has done for the past 18 years. The service is run by RAH doctors and combines with the South Australian Ambulance Service to provide advice and aid to divers across the Asia-Pacific region.

“We take about 400 calls a year,” he says.

Diving medicine is not part of normal medical school curricula. According to Dr Wilkinson, “several hundred” doctors, including many GPs, have completed training courses in Australia and New Zealand.

Dr Wilkinson’s dream is to see an increase in evidential support for the use of hyperbaric medicine in the treatment of radiation-damaged tissue.

“It’s incredible to see patients surviving [cancer] but suffering and then to get the opportunity to see them improve over a couple of months of hyperbaric oxygen treatment.”

His other wish is to discover just what exactly is going on when diabetic patients spend time in a hyperbaric chamber.

“Who knows where it could go,” he says. “Perhaps we could delay or defer the onset of type 2 diabetes.”

Meanwhile, Dr Wilkinson is happy to have to spotlight on himself and his OAM, if that means hyperbaric medicine gets some recognition.

“I have many colleagues who are not aware of what hyperbaric medicine can do – hopefully this might lead them to take a look.”