Preliminary results of a survey of the use of antimicrobial agents as prophylaxis in orthopedic surgery

An epidemiological survey of the use of antimicrobial prophylaxis in Italian hospitals was carried out under the auspices of the Journal of Chemotherapy. Out of 500 Italian orthopedic centers queried, 225 agreed to participate in this study. A total of 136,321 surgical procedures were reported in the 166 centers reporting complete answers on type of surgery. They comprised hip and knee prosthesis (13.9%), spine surgery (4%), hip endoprosthesis (5.2%), osteosynthesis (26.9%), arthroscopy (24.4%), and others (25.5%). Perioperative antimicrobial prophylaxis was used in 75% of operations (ranging from 57.1% to 99.4% in arthroscopy and joint prosthesis, respectively). Short term (<24 h) antimicrobial prophylaxis was performed in 38.4% of the 206 centers answering this question correctly. 61.1% of centers employed single agent prophylaxis and 70.8% of these prescriptions were betalactam antibiotics. Bacteriological analysis revealed Gram-positive isolates in 73.3% of cases. Methicillin resistance was present in 45% of 915 tested strains. Out of 4221 patients with high risk of infectious complications (joint prosthesis surgery) given antimicrobial prophylaxis in 46 centers, the percentage of surgical wound infections was overall 2.1%, while that of non-surgical wound infections was 3.6%. The total infection rate was decreased by about half in association with long-term (>24 h) as compared to short-term (<24 h) antibiotic treatment (3.7% vs 7.6%, respectively), and with use of antibiotic drug combinations vs single antibiotic drugs (3.9 vs 6.6%, respectively). The incidence of surgical-site infection was not decreased by extending the chemoprophylaxis for more than the first 24 h after surgery, while it was reduced from 2.5 to 1.4% by use of combination antibiotic therapy.