Surgical site infections (SSIs) are the most common healthcare-associated infections in patients undergoing surgery in the United States, contributing significantly to increased morbidity, mortality, and healthcare costs.1 The increased number of outpatient surgeries and the increasing number of drug-resistant organisms present additional challenges in the management of SSIs. An estimated 27 million surgical procedures are performed each year, and the rate of SSIs in patients undergoing surgery ranges from 2% to 5%, for an annual incidence of 540,000 to 1.3 million SSIs.1 Infection is the cause of death in 77% of surgical patients who have SSIs at the time of death.1 The U.S. Department of Health and Human Services has set a goal of reducing SSIs by 25% nationally by 2013.3
Before Joseph Lister introduced the principles of antisepsis in the mid-19th century, surgical patients commonly developed postoperative SSIs and often died. Lister's work helped reduce the incidence of postoperative infection, making surgery a safer discipline that could lessen suffering and prolong life.4
SSIs cause a significant number of complications and deaths among hospitalized patients, despite advances in infection control practices such as improved OR ventilation, sterilization methods, barriers, surgical technique, hair removal and skin preparation, surgical wound dressing protocols, blood glucose control, and availability of antimicrobial prophylaxis.5
Defining and recognizing SSI
An SSI is an infection that develops within 30 days after a surgical procedure, or within 1 year if an implant was placed and the infection appears to be related to the surgery.1,4 SSIs can be superficial, involving only the skin, or may be more serious, involving subcutaneous tissue, organs, or implanted material.6
A thorough assessment can help you recognize an SSI early. Look for these signs and symptoms:
* Malaise, a common symptom of infection, is defined as reduced energy, increased tiredness, and an overall aching feeling. Malaise may be attributed to normal postoperative recovery if the patient reports feeling better each postoperative day. If not, malaise may indicate infection.
* Fever may be normal postoperatively if it's low-grade (100[degrees]F [37.8[degrees]C] or less). If it's trending upward or is 101[degrees]F (38.3[degrees]C) or greater, with or without chills and loss of appetite, alert the surgeon, as fever may lead to dehydration and headache.
* Pain typically is present postoperatively, but should steadily diminish as healing takes place. A patient who reports an increased pain level may have an SSI. Be sure pain assessments are consistent; use a reliable, validated pain intensity rating scale and document the location, description, and radiation of the pain and the patient's response to any analgesics administered.
* Induration of the incision may be a sign of infection. This abnormal firmness of the tissue underneath and surrounding the incision makes the incision appear swollen.
* Erythema, or redness at the incision site, is a normal finding, but should steadily diminish as healing progresses. Red streaks radiating from the incision site aren't normal and should be reported to the surgeon.
* Increased warmth at the incision site indicates a systemic reaction by the body in an attempt to combat infection.
* Serous or serosanguinousfluid may drain from the surgical wound or surgical drain postoperatively, but shouldn't be foul-smelling. Pus is an indication of infection and may be blood-tinged, white, yellow, or green.
Clinical and lab findings
Effective and timely antimicrobial treatment is important for patients with SSIs because delayed diagnosis and treatment substantially increase mortality. Blood tests used to help diagnose infection include white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP).7
For early detection of postoperative infections, CRP may be useful.8 CRP is an acute-phase reactant and is a marker of general tissue damage and inflammation. CRP is superior to WBC count and ESR in detecting acute inflammation because it activates sooner and decreases more rapidly when inflammation subsides.8,9 Obtaining a preoperative CRP level is important in order to rule out preexisting infection. Keep in mind that CRP levels generally increase for several days after surgery and trauma, plateauing on days 2 to 4.7
WBC count and ESR, although useful, suffer from several drawbacks, including low sensitivity and specificity for infection and sepsis.7
More recently, other biomarkers for infection and sepsis have become available; the most promising are procalcitonin and neutrophil CD64. Further research is being performed before these markers become accepted as part of the routine protocol for diagnosis of infections.7
A wound culture can help determine the specific bacteria causing the infection, and which drugs should be used to treat it.
Beyond simple but imperative preventive measures, the path to improving early detection and diagnosis of SSIs lies in the hands of the clinicians providing direct patient care and those teaching patients to assess their surgical wounds at home. Close tracking of postoperative assessment data and noting trends that suggest an SSI, along with confirmation from lab tests, may prove to be the most reliable indicators of SSIs.
REFERENCES