The risk related to surgical site infections after hip endoarthroplasty--surveillance outcome analysis in two Polish orthopaedic centres.

BACKGROUND Surgical Site Infections (SSIs) are a major infection control problem in modern hospitals. The aim of this study was to carry out an epidemiological analysis of surgical site infections diagnosed in patients after hip endoarthroplasty in two clinical centres in 2005. MATERIAL AND METHODS Surveillance of hospital infections was performed according to the definitions and criteria of the National Nosocomial Infections Surveillance System (NNIS). 187 and 479 surgical procedures were performed in two hospital wards. RESULTS Incidence was found to be 7.5% and 2.3%, respectively. Deep infections were the dominant type in Clinical Centre I and superficial infections predominated in Clinical Centre II. In one of the centres, an effective post-discharge infection registration system was implemented (63.6% of the cases); the second centre registered SSI cases predominantly during the patients' stay on the ward. Gram-positive cocci were the most common aetiological factor for all types of SSIs. All Staphylococcus aureus strains isolated were MSSA and the main therapeutic problem was multi-resistant coagulase-negative staphylococci. CONCLUSIONS The results of the study point to a significantly higher SSI incidence in the population of patients in Clinical Centre I. Prolonged preoperative hospital stay was shown to raise the risk for SSI. The technical skill of the surgeons, expressed as the number of procedures carried out at each centre, was another significant factor. Drug resistance of isolates points to the problem of multi-resistant coagulase-negative staphylococci infections in the study population.