159. PREOPERATIVE AMBULATORY SCREENING OF PATIENTS CARRYING STAPHYLOCOCCUS AUREUS OR PRESENTING URINARY TRACT COLONIZATION BEFORE ORTHOPAEDIC SURGERY

Abstract

Purpose of the study: Prevention of operative site infections (OSI) in orthopaedic surgery requires strict observation of validated practices during hospitalisation and in the operative theatre, review of morbidity and mortality, and surveillance of OSI. Certain intrinsic patient-related risk factors of OSI cannot be controlled without direct implication of the patient and the referring physician. Search for Staphylococcus aureus (SA) colonisation and bacteriuria should be done in the ambulatory setting, before hospitalisation. The purpose of this work was to evaluate the feasibility of a search for SA in the nasal swabs and urine samples in patients scheduled for prosthesis surgery.

Material and methods: This was a prospective study on 335 patients who had a total hip arthroplasty (THA) or a total knee arthroplasty (TKA) from January 1, 2007 to December 31, 2008. Bacteriological tests were performed before hospitalisation. Before hospitalisation, the patient and the primary care physician were give information on the proper procedure for chemical decontamination. The results of these laboratory tests were analysed and OSI were followed.

Results: Three hundred thirty-five patients (195 THA and 143 TKA) were included; the sex-ratio was 0.95 M/F. Sixty-one patients (18%) exhibited SA colonization, including two meticillin resistant strains. Urine samples were positive in 30/323 patients (9.3%). Three patients presented an early OSI: two infections of a revision THA and one infection of a revision TKA. Two of these patients had an SA infection, including one who was colonized and had applied the chemical decontamination protocol before hospitalization.

Discussion: By treating bacteriuria before hospitalization, deferral of the scheduled operations could be avoided. Laboratories must run two sets of tests to search for both met-S and met-R SA, which in our experience was not always the case despite written prescriptions. Implementation of chemical decontamination of the nasal passages and skin before surgery requires a well-established cooperation between the primary care physician and the hospital. The three infections recorded in this series involved revision procedures, with a context of rheumatoid polyarthritis for two patients.

Conclusion: Systematic screening for SA colonization in orthopaedic surgery remains a subject of debate, particularly concerning the cost-efficacy balance, but can be quite useful in certain situations such as revision or prosthetic surgery in immunodepressed patients.