Airborne bacteria and surgical infection.

From the inception of modern surgery, the significance of airborne microbes to surgical infection has been controversial. The success of aseptic methods led the majority of surgeons early in this century to discount the airborne route. Despite aseptic disciplines, a significant level of infection continued and from 1930 onwards renewed attention was directed towards the air. Many studies over the following 25 years produced anecdotal and suggestive evidence that this was relevant and that a reduction in surgical sepsis followed a reduction in the numbers of airborne bacteria in the operating room. To this day, however, there has been no wholly satisfactory demonstration of this. Such a demonstration requires comparison of the outcome of a considerable number of surgical operations performed during the same period by the same surgeons under conditions which differ only in the levels of air contamination. Recent developments in orthopedics have resulted in large numbers of essentially similar operations on a site susceptible to infection but free from sources of bacteria within itself. Under these conditions, there is evidence that the numbers of bacteria contaminating the would at the end of the procedure are substantially fewer when the levels of airborne bacteria are reduced.