Reduction in MRSA Cardiothoracic Surgical-Site Infections

Surgical-site infection (SSI) is a clinically significant complication of surgical interventions. Despite advances in infection control and prevention, SSIs caused by methicillin-resistant Staphylococcus aureus (MRSA) continue to plague certain types of surgery, including cardiothoracic procedures. On February 1, 2007, a large, community-based hospital in New York State initiated a quality-improvement program designed to reduce MRSA infections on the cardiac surgical service. Now, researchers report the results of this program.

The improvement project included five key components:

• Screening of staff for nasal MRSA carriage; decolonization of carriers

• Screening of patients for nasal MRSA carriage before or just after admission; vancomycin prophylaxis for carriers

• Use of nasal mupirocin calcium ointment for all patients

• Application of mupirocin to exit sites after removal of chest and mediastinal tubes

• Rescreening of all patients at hospital discharge

SSI rates were compared between two groups: a baseline cohort (2766 patients who underwent cardiothoracic surgery between January 1, 2004, and January 31, 2007) and an intervention cohort (2496 patients who underwent such surgery between February 1, 2007, and January 31, 2010).

The MRSA SSI rate was 93% lower in the intervention cohort than in the baseline cohort (0.08% vs. 1.2%; P<0.001). A reduction seen in SSIs overall was predominantly attributable to the decrease in MRSA SSIs; the rate of SSIs caused by other organisms was similar between groups (0.7% and 1.0%; P=0.36). The rate of MRSA SSIs among patients who underwent noncardiac surgery at the same hospital did not change during the study period.