More periop oxygen halves surgical wound infection rate

Administration of 80% oxygen during elective colorectal surgery and for two hours afterward reduces by 50% the rate of surgical wound infections compared with administration of 30% oxygen, according to a new report.1

Researchers at the University of California at San Francisco examined the effects of administering both concentrations of oxygen during and for two hours after elective colorectal surgery in 500 patients. The rationale for providing the higher oxygen concentrations is that neutrophils require oxygen for the production of bactericidal superoxide radicals. Therefore, bactericidal activity is strongly related to the partial pressure of oxygen in the tissues. Surgery disrupts the local vascular supply and causes thrombosis, with associated local wound apoxia, which is corrected by increasing arterial oxygen tension beyond that required to saturate the red blood cells. Arterial oxygen saturation, subcutaneous oxygen tension, and intraoperative oxygen tension in muscle were significantly higher among the patients who received 80% oxygen, the authors report.

Although infections prolonged hospital stays by an average of a week, there was no overall difference between the two groups in the duration of their hospitalizations. According to the results of prior studies, infections after surgery for cancer can add an average of $12,500 to a patient’s hospital bill. More patients in the 30% oxygen group than in the 80% oxygen group required ICU admission, and more patients in the 30% group died, though neither difference was statistically significant, the investigators note.

Reference

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