Give surgical patients a breath of fresh air

SSIs and costs may fall as a result

Grief R, Akca O, Horn EP, et al. Supplemental perioperative oxygen to reduce the incidence of surgical-wound infection. N Engl J Med 2000; 342:161-167.

The administration of supplemental oxygen during colorectal resection and for two hours afterward halved the incidence of surgical-wound infection, the authors found. "Because the cost of and risk associated with supplemental perioperative oxygen are trivial, the provision of supplemental oxygen appears to be a practical method of reducing the incidence of this dangerous and expensive complication," they emphasize.

Destruction by oxidation is the most important defense against surgical pathogens and depends on the partial pressure of oxygen in contaminated tissue. An easy method of improving oxygen tension in adequately perfused tissue is to increase the concentration of inspired oxygen, the authors surmised.

They randomly assigned 500 patients undergoing colorectal resection to receive 30% or 80% inspired oxygen during the operation and for two hours afterward. Anesthetic treatment was standardized, and all patients received prophylactic antibiotic therapy. With use of a double-blind protocol, wounds were evaluated daily until the patient was discharged and then at a clinic visit two weeks after surgery. Wounds with culture- positive pus were considered infected. The surgeon, who did not know the patient’s treatment-group assignment, determined the timing of suture removal and the date of discharge.

The arterial and subcutaneous partial pressure of oxygen was significantly higher in the patients given 80% oxygen than in those given 30%. Among the 250 patients in the former group, 13 (5.2%) had surgical-site infections. However, 28 (11.2%) of the 250 patients given 30% oxygen had infections. "The administration of supplemental oxygen during colorectal resection and for two hours afterward reduced the incidence of wound infection — one of the most serious common complications of surgery — by half," the authors concluded. Moreover, surgical-wound infections are expensive. For example, postoperative infections in patients with cancer add an average of $12,500 per patient to the cost of care. "The one-week-longer hospitalization in patients with infection in our study is consistent with findings in previous studies and indicates that the infections were clinically important, as do the higher numbers of admissions to the intensive care unit and of deaths in the group given 30% oxygen," they emphasized.

The researchers used a sealed mask and a manifold system to deliver oxygen postoperatively so that administration could be controlled precisely. However, similar amounts of oxygen can be delivered through conventional non-rebreathing masks, they reported. The postoperative administration of oxygen through a conventional mask introduces little if any extra cost, because virtually all patients are given some oxygen after surgery, they noted.