Antibiotic resistance profiles of deep surgical site infections in hip hemiarthroplasty; comparing low dose single antibiotic versus high dose dual antibiotic impregnated cement

The incidence of fractured neck of femur (FNOF) is increasing yearly. Many of these patients undergo hip hemiarthroplasty. High dose dual-antibiotic cement (HDDAC) has been shown to reduce rates of deep surgical site infection (SSI) when compared to the current standard low dose single-antibiotic cement (LDSAC) in a quasi-randomised controlled trial. Some concerns exist regarding the use of HDDAC and the development of antibiotic resistance. We reviewed cases of infection in LDSAC and HDDAC bone cement with regard to causative organism and resistance profile. A retrospective analysis was undertaken of all hemiarthroplasties within our trust from April 2008 to December 2014. We identified all patients in this time period who acquired a deep SSI. The infecting organisms and susceptibility patterns were collated for each cement. We identified 1941 hemiarthroplasties. There were 38 deep surgical site infections representing an infection rate of 3.4% in LDSAC patients and 1.2% in HDDAC patients. The majority of infections were polymicrobial. was the most commonly isolated organism. It accounted for a larger proportion of HDDAC than LDSAC infections (p