TUESDAY, Oct. 25, 2005 (HealthDay News) -- Giving higher concentrations of supplemental oxygen during elective colorectal surgery reduces the risk of surgical site infections, a new study found.
And the practice comes with very little down side, if any, said the authors of the report in the Oct. 26 issue of the Journal of the American Medical Association.
"Wound infections are among the most common serious complications of surgery. Supplemental oxygen costs only a few cents per patients and is essentially risk-free. Providing extra oxygen halves the risk of infection and should be used in most patients," said study co-author Dr. Daniel I. Sessler, chairman of the department of outcomes research at the Cleveland Clinic Foundation. "Now that two large studies with a total of 800 patients clearly indicate that supplemental oxygen is beneficial, we expect that it will become common practice. Consequently, fewer patients will suffer wound infections."
"People aren't doing the simple things they could be doing," added Dr. Jimmy Windsor, an anesthesiologist and critical-care physician at the Ochsner Clinic Foundation in New Orleans.
"It's the simple things -- that's what we need to start doing. We can't let things fall through the cracks," said Windsor, who was not involved with the study.
Infections occurring at the site of the colorectal surgery may be the most common serious complication of surgery and anesthesia, prolonging hospitalization by an average of one week and doubling the risk of death, the researchers said.
Ways to prevent such infections are well known and include antibiotics given at appropriate times, clipping rather than shaving hair and maintaining normal body temperature during the operation.
The role of supplemental oxygen in preventing these infections has been debated. One study, conducted in 2000, showed that providing 80 percent oxygen throughout the surgery and for two hours afterward cut infection risk by half, compared with patients who got 30 percent oxygen. By contrast, a less rigorous study, conducted in 2004, found that supplemental oxygen doubled the risk of infection.
For the new study, the researchers in Spain randomly selected 300 patients aged 18 to 80 undergoing elective colorectal surgery in 14 Spanish hospitals to receive either 80 percent oxygen or 30 percent oxygen during the procedure and for six hours after.
Almost one-quarter (24.4 percent) of patients receiving 30 percent oxygen developed surgical site infections, compared to only 14.9 percent of those receiving the purer mix.
The 80 percent mixture resulted in an absolute risk reduction of 6 percent, the study authors said.
"This helps to settle [the debate]," said Windsor, who said he had already been using supplemental oxygen.
Oxygen kills bacteria by activating the immune system's neutrophils, which are white blood cells that are among the first to arrive at an infection site.
There is little risk to the practice, Windsor said. "There's always a down side to everything. If you have damaged lungs, you should be doing the lowest possible oxygen," he said. But even then, the oxygen would have to be given for hours to days to pose any real danger.
Sessler confirmed the point. "The major potential risk of supplemental oxygen is collapse of lung spaces or atelectasis," he said. "However, we have shown in a previous study, since confirmed by others, that 80 percent oxygen does not cause any pulmonary problems whatsoever. Basically, the drug is inexpensive, risk-free, and highly effective."
An accompanying editorial in the journal also saw little reason not to adopt the practice.
"Surgeons should encourage the broader use of higher oxygen tensions for their patients undergoing major abdominal procedures and be more involved in quality improvement initiatives aimed at reducing [surgical site infections,]" wrote Dr. E. Patchen Dellinger of the University of Washington School of Medicine in Seattle.
"These low-risk interventions are probably very, very effective but are not being practiced," Windsor echoed. "We need to pay attention to the small details."
More information
The Institute for Healthcare Improvement has more on surgical site infections.
