Background
An appropriately feared complication of operations, surgical site infections (SSIs) are infections associated with high economic costs and significantly worse clinical outcomes (1). Defined as infections of the superficial incision site, deep incision space, or organ space, SSIs add additional cost ranging from $2,700 to $26,000 per episode according to CDC’s National Nosocomial Infections Surveillance System. Patients who develop an SSI have hospital lengths of stay (LOS) in excess of 7 days longer and are 60% more likely to spend time in the intensive care unit than are patients without an SSI. A patient with an SSI is five times more likely to be readmitted to the hospital and is twice as likely to die (2).
Unfortunately, surgical site infections are common. Among healthcare-acquired infections, SSIs rank second only to urinary tract infections in frequency, making them more common than bloodstream infections and nosocomial pneumonia (3). There are approximately 30 million operations annually in the United States and an SSI complicates 2–5% of clean extra-abdominal sites. The rate is much higher for intra-abdominal operations, approaching 20% (1). Because most SSIs begin within 2 hours of contamination, the perioperative period is the most crucial for development of an SSI (4). By offering clinical expertise in the practice guidelines that reduce the risk of SSIs, hospital medicine programs can help patients and hospital systems lower morbidity, mortality, and costs associated with this complication. Adherence to best practices will likely require coordinated, multidisciplinary process improvement.
Several important interventions fall directly under the control of the anesthesia and surgical teams, such as administering perioperative oxygen, ensuring perioperative normothermia, and avoiding shaving of the surgical site. In coordinated quality improvement efforts, members of the operative team should assume direct responsibility for the performance of these measures. But the performance of two important interventions in this decisive period is likely to be significantly enhanced by the presence of focused hospitalist surgical co-management: antimicrobial prophylaxis and perioperative glycemic control (Table 1).
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Antimicrobial Prophylaxis
Studies overwhelmingly show a marked reduction in the relative risk of SSIs with the use of antibiotic prophylaxis (1). In June 2004, the National Surgical Infection Prevention Project (NSIPP) published an advisory statement on antimicrobial prophylaxis in which it outlined three performance measures for quality improvement in prevention of SSIs:
- The proportion of patients who have parenteral antimicrobial prophylaxis initiated within 1 hour before surgical incision
- The proportion of patients provided with a prophylactic antimicrobial agent that is consistent with currently published guidelines, and
- The proportion of patients whose prophylactic antimicrobial therapy is discontinued within 24 hours after the end of surgery (5)
Pooled data suggest that attention to timing makes a favorable difference in SSI rates (1). Fully administering the appropriate antibiotic within 60 minutes of incision ensures that serum and tissue drug levels exceed the MICs of the most likely contaminating organisms. Dosing the antibiotic immediately prior to the start of surgery also provides the best opportunity to extend therapeutic levels for the duration of the surgery. The fact that anesthesia and surgical teams are in the most practical time-space positions to apply this measure underscores the multi-disciplinary and process-level efforts necessary to reduce SSI rates.
When it comes to the choice of antimicrobial and the duration of its use, hospitalists may find themselves in superior positions of impact. Familiarity with recommendations of the NSIPP advisory statement (summarized in Table 2) promotes evidence-based selection of antibiotic prophylaxis based on patient-specific factors: type of operation and presence of true drug allergies (5). Compared with other members of the surgical co-management team, hospitalists are more likely to be aware of relevant patient-specific risk factors such as the likelihood of colonization with methicillin-resistant Staphylococcus aureus (MRSA). For example, in patients colonized with MRSA, hospitalists might consider vancomycin as the alternative agent for prophylaxis. Free access to the NSIPP advisory statement is available at www.journals.uchicago.edu/CID/journal/issues/v38n12/33257/33257.html.