Reduced costs for Staphylococcus aureus carriers treated prophylactically with mupirocin and chlorhexidine in cardiothoracic and orthopaedic surgery.

A multi centre double-blind randomised-controlled trial (M-RCT), carried out in the Netherlands in 2005-2007, showed that hospitalised patients with S. aureus nasal carriage who were treated prophylactically with mupirocin nasal ointment and chlorhexidine gluconate medicated soap (MUP-CHX), had a significantly lower risk of health-care associated S. aureus infections than patients receiving placebo (3.4% vs. 7.7%, RR 0.42, 95% CI 0.23-0.75). The objective of the present study was to determine whether treatment of patients undergoing elective cardiothoracic or orthopaedic surgery with MUP-CHX (screen-and-treat strategy) affected the costs of patient care. We compared hospital costs of patients undergoing cardiothoracic or orthopaedic surgery (n=415) in one of the participating centres of the M-RCT. Data from the 'Planning and Control' department were used to calculate total hospital costs of the patients. Total costs were calculated including nursing days, costs of surgery, costs for laboratory and radiological tests, functional assessments and other costs. Costs for personnel, materials and overhead were also included. Mean costs in the two treatment arms were compared using the t-test for equality of means (two-tailed). Subgroup analysis was performed for cardiothoracic and orthopaedic patients. An investigator-blinded analysis revealed that costs of care in the treatment arm (MUP-CHX, n=210) were on average €1911 lower per patient than costs of care in the placebo arm (n=205) (€8602 vs. €10513, p=0.01). Subgroup analysis showed that MUP-CHX treated cardiothoracic patients cost €2841 less (n=280, €9628 vs €12469, p=0.006) and orthopaedic patients €955 less than non-treated patients (n=135, €6097 vs €7052, p=0.05). In conclusion, in patients undergoing cardiothoracic or orthopaedic surgery, screening for S. aureus nasal carriage and treating carriers with MUP-CHX results in a substantial reduction of hospital costs.