Prevention: Surgical Site Infections

BY DANIELLE SCHEURER, MD, MSC, FHM

Of the 27 million operations performed annually in the United States, about 290,000 are associated with SSIs. These result in approximately 8000 deaths a year [CDC fact sheet]. These infections prolong the hospital stay by a mean of 7.5 days and cost between $130 million and $845 million a year (PMID: 15972163). In recognition of the magnitude of the problem, creating incentives for reducing the risk of SSIs is a major priority for local, state, and national agencies. In 2003, the Joint Commission made the prevention of SSIs a National Patient Safety Goal. In 2002, the Centers for Medicare and Medicaid Services (CMMS) created the Surgical Infection Prevention Collaborative, which identified 3 performance measures related to antibiotics (Table 1) for 7 procedures (abdominal hysterectomy, vaginal hysterectomy, hip arthroplasty, knee arthroplasty, cardiac surgery, vascular surgery, and colorectal surgery). The CMMS requires these 3 performance measures (appropriate timing and duration of antibiotics) in the quality measure set required for the inpatient prospective payment system.

In addition, the Surgical Care Improvement Project (SCIP) is a multiagency collaboration created in 2003. In addition to the 3 performance measures from CMMS, SCIP also focuses on 3 additional performance measures: proper hair removal (Table 1), diabetic control (blood sugar < 200 on postop days 1–2) in cardiac surgery patients, and perioperative normothermia for colorectal surgery patients. The Institute for Healthcare Improvement (IHI) recommends excellence in these same 6 performance measures, which are included in the 100,000 and 5 million lives campaigns.

The risk of occurrence depends on the patient risk category and the type of surgery. According to the National Nosocomial Infection Surveillance (NNIS), the patient risk category (0–3) depends on the American Society of Anesthesiologists (ASA) preoperative assessment score, the contamination of the wound, and the duration of the surgery (PMID: 11486302).

Surgical risk is site dependent; The highest rates occur after abdominal and organ transplant surgeries; genitourinary, gynecologic, orthopedic, vascular, and cardiothoracic surgeries are of intermediate risk; and the lowest rates occur after endocrine and eye surgeries.

Several guidelines exist to guide health care providers in how to mitigate the risk of developing an SSI. Most of these recommendations come from the Centers for Disease Control and Prevention (CDC) Hospital Infection Control Practices Advisory Committee (HICPAC) guidelines and the Society for Healthcare Epidemiologist of American (SHEA)/the Infectious Disease Society of American (IDSA) guidelines. Table 1, derived from the above-mentioned practice guidelines, outlines the risk factors associated with SSI risk, and interventions for mitigating the risk. The preventive interventions that hospitalists can most likely have an impact on are highlighted in bold.

Preoperative interventions include controlling blood sugar, counseling smoking cessation, identifying and treating remote infections before the surgery, choosing the correct antibiotic and dose based on the patient and the surgery (Table 2), and ensuring that the antibiotic is delivered with an hour of the incision. Eradication of staphylococcal nasal carriage was recently shown in a randomized controlled trial to reduce the risk of SSIs, but this has not been incorporated into any guidelines and is not currently considered the standard of care.

Peri- and postoperative interventions include controlling blood sugar, ensuring continued smoking cessation, careful hand washing before and after any contact with the wound, and ensuring that the antibiotic is discontinued within 24 hours.

Table 1. Factors Associated with SSI Risk and Interventions to Reduce Risk (HICPAC, 1999; SHEA, 2008)
[shaded areas are hospitalist-specific interventions/areas of awareness]

**A recent randomized controlled trial found that preoperative decolonization of Staphylococcus aureus nasal carriage reduced the risk of SSIs.
**A recent randomized controlled trial found chlorhexidine-alcohol significantly more effective than povidine-iodine for the prevention of SSIs.

Table 2. Antibiotics for Prevention of SSIs (Bratzler, ACOG)

*Should combine with bowel prep: neomycin/erythromycin or neomycin/IV metronidazole.