Exposing wounds to pure oxygen can help them to heal more quickly, according to doctors.

Researchers in the United States have found that applying bags of pure oxygen onto the skin can help even the worst wounds to heal.

They said the technique could have huge benefits for patients with a wide range of disorders, from bedsores to ulcers.

There was much less scarring than we had anticipated Dr Chanden Sen

They also believe it could allow some patients, who would otherwise need surgery, to avoid going under the surgeon's knife.

Dr Chanden Sen and colleagues at Ohio State University based their findings on a study of 30 patients.

Each of these patients had at least one wound, ranging from post-surgical wounds to injuries resulting from ulcers.

Many of the patients were attending a special wound healing clinic, after their wounds failed to heal properly.

Doctors placed a bag containing pure oxygen over patients' wounds for 90 minutes a day for four days, followed by a three-day rest period.

This cycle was repeated for as long as the wound appeared to be healing with doctors using photographs to determine if progress was being made.

They found that three out of four wounds healed properly using the oxygen bags.

Wounds incurred as a result of surgery had the best success rates. These were followed by ulcers on the hand and legs. Bedsores were the least likely to clear up completely, although they still had a success rate of 44%.

The doctors also found that scarring was significantly reduced.

"There was much less scarring than we had anticipated," said Dr Sen. "The quality of closure is very impressive."

Gayle Gordillo, who was also involved in the study, added: "In most cases, the residual scar tissue in the healed wounds after oxygen therapy appeared to be substantially less than we would expect after treatment with more standard forms of wound care."

The doctors suggested their findings could help to treat people who have suffered skin injuries as a result of an accident.

"Topical oxygen is a simple form of therapy, which if necessary, many people could use at once such as in the case of a public disaster," said Dr Sen.

"These bags are also suitable for use in the field, so the treatment may be an option for deployed military troops."

But he added: "Further research testing the potential of topical oxygen therapy is warranted."

The study is published in the journal Pathophysiology.