Wound Infection

Any consideration of infection following clean surgery, particularly cardiothoracic must include both exogenous and endogenous sources. The MRC Study on Hip Surgery presents a particular challenge. Although uncontrolled antibiotic prophylaxis reduced the infection rate almost as well as a laminar flow operating theater, further analysis of the data correlated the incidence of infection with the theater air counts and more significantly considered the sources of Staphylococcus aureus infections. Data on swabs from patient and theater staff at the time of surgery were available for 14 of the 28 patients who subsequently developed deep infections with S. aureus . Overall 25% of patients and 33% of staff were carriers. Bacteriophage typing revealed that 2 patients, 2 surgeons and 7 theater staff carried the infecting type at the time of the surgery. In two instances there was no correlation and in the last a member of the surgical staff on leave at the time carried the relevant strain. This at least provides a clue that exogenous infection can be important, and justifies attempts to clean the environment as well as the patient.