Chamber of secrets:

how hyperbaric medicine is helping a new wave of patients

By Dr Susannah Sherlock - January 2018
Dr Susannah Sherlock - an anaesthetist and hyperbaric specialist from UQ’s Royal Brisbane Clinical Unit - spends many hours in the depths of the Royal Brisbane and Women’s Hospital overseeing patients as they undergo hyperbaric treatment.

Dr Susannah Sherlock

When you think of hyperbaric medicine, it’s likely that the first thing that comes to mind is a scuba diver being treated for the bends. But dig a little deeper, and you’ll soon discover hyperbaric medicine is used to treat a range of chronic and acute conditions.

The RBWH Hyperbaric Medicine Unit is often the first port of call for patients requiring treatment in its submarine-like hyperbaric chamber.

The unit treats patients who go scuba diving in countries like Fiji or Vanuatu and have to be medically evacuated to Brisbane, or those who come to Brisbane from North Queensland after diving and haven’t allowed enough time to recover from pressure.

However, while hyperbaric medicine is used to treat divers with decompression illness, it’s actually more commonly used to treat people with chronic wounds.

Most patients who use hyperbaric oxygen therapy have radiation-induced injury after cancer treatment or are patients with diabetes predisposed to infections due to poor circulation.

These patients have often been experiencing wound breakdowns or problems after radiation treatment and this is one of the few treatment options they have, and the success rate is quite high so it’s worthwhile for them to have it.

What is hyperbaric medicine?

Hyperbaric oxygen therapy mobilises cells from bone marrow to travel to areas of the body which lack oxygen to help promote the growth of new blood vessels in these areas.

By taking patients to an ambient pressure greater than sea level, it helps the body heal itself.

One such patient is Denis Oswin who was diagnosed with throat cancer in 2013. After completing radiation therapy, Denis’s doctor recommended hyperbaric oxygen therapy to help regenerate his salivary glands because he was experiencing dry mouth after radiation therapy.

Before receiving hyperbaric therapy, Denis underwent a thorough screening process to ensure the treatment was appropriate. He’s now about two-thirds of the way through his treatment and is feeling positive.

What happens in the hyperbaric chamber?

As with many medical procedures, hyperbaric medicine does come with risks. The chamber’s use of pressure demands that strict safety procedures are enforced to minimise any potential fire hazards.

As part of the safety procedures, before entering the hyperbaric chamber, patients must change into cotton clothing and are prohibited from wearing makeup, perfume, jewellery or hearing aids.

Newspapers and electronic devices are also not permitted in the chamber, but patients can take a book to read or watch a movie on a special screen flooded with nitrogen to prevent any sparks. The stringent safety measures mean there’s never been a fire at the RBWH, or any other Australian hospital with a hyperbaric unit.

The treatment generally requires patients to wear an oxygen hood fed with 100 per cent oxygen gas for a two-hour session, and up to eight patients can be treated in the chamber at the same time.

Over the two hours, the chamber is taken to a pressure equivalent to 14 metres below sea level atmospheric pressure and patients are given an ‘air break’ midway through the treatment to allow their bodies a break from the oxygen.

Patients with chronic wounds receive daily treatments for up to eight weeks – about 30-40 sessions – depending on the treatment required.

A nurse is present for every session in the event of an emergency, or if a patient suffers brain oxygen toxicity which can cause a seizure. The instance of this is very rare,with only a handful of patients experiencing it in the past seven years.

Who can benefit from hyperbaric therapy?

In most cases hyperbaric treatment is beneficial for patients with chronic wounds who are otherwise healthy.

For commercial or recreational divers with the bends, the use of hyperbaric treatment is quite different.

Divers with decompression illness, or patients with other acute medical issues like gas embolism, need to undergo hyperbaric treatment for six or seven hours and possibly over a few days, depending on the case, to allow for elimination of bubbles in the body.

Decompression illness can vary from person to person – from minor muscular aches and pains, joint pain and fatigue through to serious spinal bends or arterial gas embolism which can result in paralysis or loss of life.

Diving regulations have become a little less stringent over the years, but the uses for hyperbaric medicine go far deeper, and while it’s not a ‘miracle cure’ for illnesses, it is helping people like cancer survivor Denis Oswin get back to living a healthy life.
Media: Kate Zischke, kate.zischke@uq.edu.au, +61 7 3365 5133.

Denis Oswin being treated in the hyperbaric chamber