Background: Risk factor and outcomes data pertaining to surgical
site infection in the elderly following orthopaedic operations are lacking.
The aim of this study was to identify risk factors for surgical site
infections and to quantify the impact of these infections on health outcomes
in elderly patients following orthopaedic surgery.
Methods: A risk factor and outcomes study was performed at Duke
University Medical Center, a tertiary care center, and seven community
hospitals in North Carolina and Virginia between 1991 and 2002. The study
included elderly patients in whom a surgical site infection had developed
following orthopaedic surgery and elderly patients in whom a surgical site
infection had not developed following orthopaedic surgery (controls). Outcome
measures included mortality during the one-year postoperative period and the
total length of the hospital stay (including readmissions during the
ninety-day postoperative period).
Results: One hundred and sixty-nine patients with a surgical site
infection were identified, and 171 controls were selected. The mean age of the
patients was 74.7 years. The most frequent procedures were hip arthroplasty (n
= 74, 22%) and open reduction of fractures (n = 55, 16%). The most common
pathogen was Staphylococcus aureus (n = 95, 56%). A risk factor for
surgical site infection, identified in the multivariate analysis, was
admission from a health-care facility (odds ratio = 4.35; 95% confidence
interval = 1.64, 11.11). Multivariate analysis also indicated that surgical
site infection was a strong predictor of mortality (odds ratio = 3.80; 95%
confidence interval = 1.49, 9.70) and an increased length of stay in the
hospital (multiplicative effect = 2.49; 95% confidence interval = 2.10, 2.94;
9.31 mean attributable days per infection, 95% confidence interval = 6.88,
12.13).
Conclusions: Measures for prevention of surgical site infection in
elderly patients should target individuals who reside in health-care
facilities prior to surgery. Future studies should be done to examine the
effectiveness of such interventions in preventing infection and improving
outcomes in elderly patients who undergo orthopaedic surgery.
Level of Evidence: Prognostic Level III. See Instructions
to Authors for a complete description of levels of evidence.