Study looks at new ways to heal wounds in diabetics

TORONTO — A clinical trial to study the efficacy of hyperbaric oxygen in treating chronic non-healing wounds, a frequent complication of diabetes, is now underway.

The study is being done  at the Judy Dan Wound Care Centre at the Branson division of North York General Hospital, in collaboration with the University of Toronto, McMaster University in Hamilton and Programs for Assessment of Technology in Health Research Institute (PATH). Lead investigators are Dr. Ludwik Fedorko, anesthesiologist at the University Health Network, and Dr. Ron Linden, medical director of  the Judy Dan Wound Care Centre.

Two-thirds of the funding is being provided by the Ontario Ministry of Health and Long-Term Care. The remaining third,  Linden said, will come from other sources.

In a previous interview, Linden explained that skin injuries that don’t heal can be a side effect of diabetes, especially when the condition is  not controlled by diet, exercise and/or medication.

“Blood vessels, especially the very small vessels, such as capillaries in the legs and feet, become damaged by high sugar concentrations. This impairs circulation, and not enough blood or oxygen goes to the feet.

“Cells that fight infection and allow healing don’t get enough oxygen to do their job.”

The result is that patients with uncontrolled diabetes can’t feel it when their feet are  injured, antibiotics can’t get to the site because of the poor circulation, and the wound festers.

When wound infection reaches the bones, Linden said, physicians may recommend amputation.

For the study, patients spend two hours, five days a week, usually for 30 treatments, breathing 100 per cent oxygen in a hyperbaric chamber.

“The blood cells absorb oxygen, and they and the oxygen-saturated serum, the liquid fluid  of the blood, carry it to the wound,” Linden explained.

Last year, the Dan family, in memory of matriarch Judy Dan, established the Judy Dan Wound Care Centre. Three hyperbaric chambers were bought. Through donations, the centre has been able to double the number of hyperbaric chambers and add more treatment rooms.

While hyperbaric oxygen is well known as a treatment for decompression, this  new use has shown great promise in preventing amputation.

Although most patients are diabetic, some have radiation wounds and other diseases.

“We are seeing more serious cases, people sent from other hospitals, coming on stretchers or in wheelchairs,” Linden said.

The problem, he explained, is finding funding for equipment and staff. “As a medical facility, we are not allowed to  charge a fee. Also since private care is not allowed, patients are not allowed  to pay   us.”

At the same time, he said, OHIP won’t fund the work of the centre, because there have not been any formal scientific studies to prove  its worth.

That will change, Linden hopes, with the results of the study, which is a Level 1 study, meaning it uses the strictest technique. It is double blind (neither the patient nor the doctor knows who is getting the treatment and who is just breathing room air), patients are chosen for the study virtually at random provided they have the diagnostic criteria, and there is both a study population and a control one.

Participants will be evaluated, especially concerning their quality of life, for 18 weeks, and then by a follow-up phone call after six and 12 months, he said.

“We are hoping to set standards for treatment of those with diabetes all around the world,” Linden said.

The terms of the study have been approved by the ethics committees of the University Health Network, the University of Toronto and PATH.

“If someone in the study  gets worse, we will check to see if they are on oxygen. If not, we will ensure that they get the care they need.”

The  results should be available in two to three  years, Linden said, “ depending on how fast we can enrol patients.”

There are some restrictions on who can take part in the study. There must be no other complicating factors, such as renal failure, and the patient must not be on dialysis. “But if they don’t fit the criteria,” Linden said, “they will be treated anyway.”

For more information, contact the  centre at 416-223-6600, or by e-mail at [email protected].