Methicillin-resistant staphylococci in clean surgery. Is there a role for prophylaxis?

Abstract

The incidence of infection in clean surgery (i.e. surgery with no major contamination of the operative site) should be less than 2%, although the incidence of postoperative infections can be higher in patients with various risk factors (namely insertion of foreign bodies, a compromised immune status or prolonged duration of surgery). Although antibiotic prophylaxis has been shown to reduce the incidence of postoperative infections in clean surgery, there is still no consensus regarding its use in this area. However, for clean surgical procedures that involve implantation of foreign material, grafts or prosthetic devices, prophylaxis is well accepted and justifiable, since this practice is indicated when the benefits exceed the expected risks. Staphylococcus aureus and coagulase-negative staphylococci are responsible for 70 to 90% of wound infections in this type of surgery. First and second generation cephalosporins are considered the drugs of choice for surgical prophylaxis. Cefazolin and other cephalosporins have good tissue penetration but poor coverage against methicillin-resistant staphylococci. The frequency with which methicillin-resistant staphylococci have been recovered in nosocomial infections has increased steadily during recent years. This provides a rationale for the use of alternative antibiotics, such as the glycopeptides (vancomycin and teicoplanin), for prophylaxis in clean surgery in hospitals where the prevalence of methicillin-resistant staphylococci is high. The effectiveness and tolerability of teicoplanin as prophylaxis for orthopaedic surgery involving joint replacement were analysed in 4 randomised controlled trials. Two compared teicoplanin with cefamandole, while the others compared teicoplanin with either cefuroxime or cefazolin. The overall early wound infection rates (within 3 months) in these studies were 1.1% for teicoplanin and 1.7% for the comparator cephalosporin. The overall late infection rate was 0.2% for both treatment groups. Adverse events were attributed to the drug in 1% of patients in both treatment groups. Therefore, on the basis of these trials, single dose teicoplanin is as efficacious and as well tolerated as multiple dose cephalosporin regimens for prophylaxis in prosthetic joint surgery.