Acquire the license to the best health content in the world
Contact Us

High-Pressure Oxygen Best for Monoxide Poisoning

Therapy greatly reduces brain damage, study finds

WEDNESDAY, Oct. 2, 2002 (HealthDayNews) -- High-pressure oxygen therapy is the best way to prevent brain damage in people who suffer carbon monoxide poisoning, researchers say.

The incidence of impaired mental function in patients given emergency high-pressure (also known as hyperbaric) oxygen treatment in the hours after they breathed in excess carbon monoxide was almost 50 percent lower than in patients who got normal-pressure oxygen therapy, says a report in tomorrow's issue of The New England Journal of Medicine.

The study was done because there was a sharp drop-off in calls for hyperbaric oxygen treatment after a 1999 Australian study found no difference between the two treatments, says study author Dr. Lindell K. Weaver, medical director of the hyperbaric medicine unit at the LDS hospital in Salt Lake City.

"Quite a number of emergency physicians decided that maybe they didn't need to use hyperbaric oxygen for these patients," Weaver says. So, he set up a carefully controlled real-life experiment in which half the patients sent to the hospital with carbon monoxide poisoning got hyperbaric oxygen and the other half got normal-pressure oxygen treatment.

They were typical of the estimated 40,000 Americans who need emergency treatment each year because they breathe excess amounts of carbon monoxide generated by inefficient burning of gasoline, coal, oil or other fuels. The carbon molecule binds with oxygen-carrying hemoglobin in the blood, depriving brain tissue of the oxygen it needs to function and gradually killing brain cells. Damage can be limited by flooding the blood with oxygen.

In the study, patients got three oxygen treatments over 24 hours, breathing either in a specialized high-pressure chamber or normal-pressure oxygen through a tube. The study was cut short when an analysis of brain function tests given six months and a year after treatment showed that 35 of the 76 patients who got normal-pressure therapy suffered loss of function, compared to 19 of the 76 who got hyperbaric treatment.

The study is praised as the best of its kind by Dr. Stephen R. Thom, a professor of emergency medicine at the University of Pennsylvania and author of an accompanying editorial.

"The consensus of the medical literature strongly supported hyperbaric oxygen therapy, but what was missing was a final, well-done trial," he says. "Previous trials all left one or two questions unanswered. This trial answers those questions. At this point in time, there should be no hesitation in using hyperbaric oxygen for acute carbon monoxide poisoning."

Hyperbaric oxygen facilities are available in most larger cities, Thom says, and the faster a patient is brought to one of them by calling 911, the better.

Weaver is more cautious in his view of how the study will affect emergency medical practice. "We want to make sure every emergency medical physician knows about this, but we can't be sure of what they will do with the information," he says.

One potential barrier to wider use of hyperbaric oxygen treatment is that "it is obviously very expensive," Weaver says. "But it is the right thing to do."

What To Do

You can learn about carbon monoxide poisoning from the National Safety Council or the U.S. Consumer Product Safety Commission.

SOURCES: Lindell K. Weaver, M.D., director, hyperbaric medicine unit, LDS Hospital, Salt Lake City; Stephen R. Thom, M.D., Ph.D, professor, emergency medicine, University of Pennsylvania, Philadelphia; Oct. 3, 2002, The New England Journal of Medicine
Consumer News