High performance under pressure

Hyperbaric medicine is a growing and highly specialised field of nursing. Linda Belardi reports on the world’s most advanced facility.

As the home to the world’s largest and most advanced hyperbaric chamber, Australia is fast becoming a global leader in hyperbaric oxygen therapy.

Traditionally used to treat divers with decompression illness or “the bends”, this growing field of medicine is now predominately used in the treatment of non-healing wounds and radiation damage.

Fully operational since last February, the Hyperbaric Medicine Unit at the Prince of Wales Hospital in Sydney has completed 4300 patient compressions in a mix of routine and emergency cases.

The specialist unit treats patients from across NSW who are referred from a wide range of specialties, which include radiotherapy, oncology, orthopaedics and endocrinology.

Nurse unit manager, Joanne James, was closely involved in designing the new $5.2 million, 80-tonne chamber along with engineering, manufacturing and other medical staff.

She says the safety, size and overall comfort of the upgraded facility has vastly improved. The advanced clinical unit also has the added title of having the largest doorways ever to be used in a hyperbaric chamber.

In the expanded facility, patient numbers have increased by one-third and individual waiting times have been cut dramatically. James says patient demand is strong and the service could be extended by another third.

“It certainly is a developing area of medicine, especially as public awareness grows of the benefits in specific patients. It is not a cure for all by any stretch, but for the patients we do see it is very beneficial,” she says.

The bulk of patients are treated for diabetic and vascular ulcers or complications after radiation therapy. Divers make up fewer than 10 per cent of all presentations. The unit is on call after-hours to respond to diving emergencies, threatening infections such as gas gangrene or cases of carbon monoxide poisoning.

James says hyperbaric medicine is quite distinct from other areas of nursing as it is the only form of care where the nurse actually accompanies the patient throughout the treatment. In the field, hyperbaric nurses are known as “dry divers” because physiologically the nurse is experiencing exactly what would happen to them if they were going under water.

“We are compressed with the patient. While we don’t breathe in the oxygen, we are in the chamber with them. At the very end of the treatment, we will breathe in oxygen for 20 minutes to reduce our risk of decompression illness.”

In order to practise as a hyperbaric nurse, staff need to be medically fit for compression and have completed a certified training course at one of Australia’s 12 hyperbaric units. Post-graduate certificates are also available through the University of Adelaide.

Myths and misconceptions

Sue Thurston is the clinical nurse manager at the Hyperbaric Medicine Unit at Fremantle Hospital and president of the Hyperbaric Technicians and Nurses Association (HTNA).

She says unsubstantiated claims, especially from overseas, about the effectiveness of hyperbaric oxygen therapy purporting to cure conditions such as cerebral palsy and multiple sclerosis have left a legacy of scepticism among some of the medical fraternity.

“In Australia, public hospital hyperbaric clinical units only treat conditions that have been proved through evidence-based medicine to improve with hyperbaric oxygen treatment. There is a list of 14 indications that have shown to be of benefit.”

Thurston says difficulties conducting double-blind trials in the chamber have hampered progress in clinical research in the past but acceptance has improved as more medically peer-reviewed research is published.

The indications for hyperbaric medicine are reviewed by the Medicare Services Advisory Commission, which determines the allocation of public funds on medicine based on published medical evidence.

Thurston says it is the role of the hyperbaric nurse to educate, monitor and assess the patient throughout the treatment. Patients are usually exposed to two-hour oxygen treatments for five days a week for up to six weeks.

Thurston, who comes from an intensive care background, says she most enjoys developing a sustained relationship with her patients. The extended treatment times also provide an important opportunity for nurses to conduct an ongoing assessment of the patient and to refer to appropriate resources.

“Once the patient is settled in the chamber, we have the time and opportunity to really talk to our patients. If a patient has a poor diet we can get dietetics involved or encourage some diabetes education for patients who are poorly managing their condition.”

Thurston says she enjoys the diversity of patient cases from intensive care to paediatrics, as well as treating across the lifespan.

Workforce issues

The HTNA is campaigning to implement new roles into the service to improve the career structure for nurses. In particular, the Clinical Nurse Educator (CNE) role and an expanded scope for enrolled nurses. The CNE role would support the nurse unit manager with running education courses to train additional hyperbaric nurses, as well as taking a leading role in ongoing research projects.

James says one of the strongest advantages of a small speciality area is that hyperbaric nurses often have the opportunity to drive the research agenda within the unit, along with other medical staff. “There are some really exciting research projects within this speciality and it is an area where nurses are doing quite a lot of the research.”

James says the current remuneration for on-call hours, especially due to some lifestyle restrictions, could be improved and is likely to contribute to future staff turnover and recruitment issues. The compression allowance available to Australian Defence Force personnel involved in hyperbaric medicine units is also significantly higher.

Due to the training requirements, there is also only a small casual pool of nurses to draw from, which can make finding staff problematic.

Accreditation

To strengthen standards with the industry, the HTNA is currently developing a national facility accreditation scheme.

In addition to nationally consistent staff training standards, the association believes that facility-wide quality and safety standards should also apply.

The issue was raised at the recent Undersea and Hyperbaric Medicine Society annual scientific meeting in Phoenix, Arizona, where US and international clinicians shared their experience of facility accreditation and how Australia might prepare for it.

Fast facts

Full installation of the Prince of Wales Hospital Hyperbaric chamber took eight months. It commenced partial operation in July last year and there have been more than 4300 patient compressions since opening.

About 60 per cent of patients are being treated for the ongoing effects of radiotherapy, while nearly 25 per cent have diabetic ulcers that are resistant to standard therapies.

Patients undergoing routine treatment can spend up to two hours each day, five days a week for up to six to eight weeks in a chamber. Some patients may need initial treatments of up to eight hours in duration, such as divers with decompression illness.

The new hyperbaric chamber has four internal compartments, all capable of independent compression according to patient and research requirements. The other large compartment in the chamber has been designed as a two-bed intensive care area, and a smaller compartment will use higher pressures to treat diving injuries.

The whole facility is directed from a fully computerized panel with video surveillance and voice communications to all areas.

The first hyperbaric chamber in Australia at Prince Henry Hospital in Sydney’s east was designed for open-heart surgery under hyperbaric conditions, but this application ceased when the heart and lung machine was invented.

How it works

Hyperbaric oxygen therapy has been in use for over 50 years and involves the intermittent inhalation of 100 per cent oxygen. Breathing a gas under increased pressure will absorb more of that gas at the cellular level and promote healing.

The effects of the treatment for chronic wounds last beyond the two-hour compression treatment.

Patients are compressed to an equivalent pressure of diving to 15 metres underwater and treated with 100 per cent oxygen. Because of the pressure changes, patients and staff need to equalise the pressure in their middle ear, much like when landing in an airplane.

It is not without complications such as ear barotrauma and oxygen toxicity. However, the incidence of oxygen toxicity is rare and has been shown to be one in 600 patients. Patients can receive hyperbaric oxygen treatment in multi-place or a monoplace chamber.

A multi-place chamber is designed to hold two or more people and the chamber is pressurised with air and patients breathe oxygen via mask, a hood or endotracheal tubes. These chambers are suitable for routine treatments and can accommodate a multiple number of patients in a single treatment session. Clinical staff accompany patients in the hyperbaric chamber at all times.

In a monoplace chamber, the patient is placed in a large long clear tube-like chamber made from perplex and metal and is pressurised with 100 per cent oxygen.