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At-Risk Patient: Surgical Site Infections

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Skin is a natural barrier against infection. Despite the provision of precautions and protocols to prevent infection, any surgery or procedure that breaches the skin can lead to an infection. Infections that occur on the part of the body where the surgical procedure took place are called surgical site infections (SSIs). The chances of a patient developing an SSI post-surgery are about 1% to 3%. Surgical site infections can sometimes be superficial infections involving the skin only. Other SSIs are more serious and can involve tissues under the skin, organs, or implanted material.

Infection at the surgical site remains the second most common adverse event occurring to hospitalized patients and a major source of morbidity following surgical procedures. Infections are more likely to occur after surgery on parts of the body that harbor lots of germs (or are susceptible to cross contamination). Surgical site infections have been shown to increase mortality, readmission rate, length of stay, and cost for patients who incur them.

Symptoms of Surgical Site Infections

Symptoms of SSIs include: a delay in healing of the surgical site, discoloration of the tissue around the surgical site, a foul odor or pus coming from the incision site, pain or tenderness in the area around the incision, severe swelling, and the incision may be hot to the touch.


The most common causes of surgical site infections are invasive procedures that penetrate bacteria-laden body sites, for example the bowel. The CDC stratifies the increased likelihood and extent of bacterial contamination during the surgical procedure into four separate classes:

  • Clean wounds: The wound is considered clean when the operative procedure does not enter into a normally colonized viscera or lumen of the body. Surgical site infection rates in this class of procedures are less than 2%, depending upon clinical variables, and often originate from contaminants in the operating room environment, from the surgical team or, most commonly, from skin.
  • Clean-contaminated wounds: A site is considered clean-contaminated when the operative procedure enters into a colonized viscera or cavity of the body, but under elective and controlled circumstances. SSI rates in this class of procedures range from 4% to 10%.
  • Contaminated wounds: When gross contamination is present but no infection is obvious, a surgical site is considered to be contaminated. As with clean-contaminated procedures, the contaminants are bacteria that are introduced by soilage of the surgical field. Surgical site infection rates in this class of procedures can exceed 20%.
  • Dirty wounds: If active infection is already present in the surgical site, it is considered a dirty wound. Pathogens of the active infection as well as unusual pathogens will likely be encountered. Surgical site infection rates in this class of procedures can exceed 40%.

Risk Factors

Some variables, such as age and gender, are obviously not amenable to change or improvement. Although several other potential factors are, such as: obesity, nutritional status, smoking, proper use of antibiotics and intraoperative technique. Other risk factors include: diabetes mellitus, perioperative hyperglycemia, having surgery that lasts more than two hours, having other medical problems or diseases.


Surgical site infections have been shown to increase mortality, readmission rate, length of stay, and cost for patients who incur them.

Treatments of Surgical Site Infections

Antimicrobial dressings can be used prophylactically to reduce the chance of SSI’s. Many times they are applied in the OR especially for cardiothoracic surgery or any surgery involving implants such as joint replacements, pacemakers, organ transplants, or hernia mesh surgeries. They are also important to use in those who may be immunocompromised.

If necessary, the incision should be opened, the infected material removed, and the wound dressed to allow for healing by secondary intention. Sometimes additional surgery or procedures may be required to treat the SSI.

Most SSIs can be treated with antibiotics. Topical antibiotics are sometimes used to reduce microbial contaminant exposure following surgical procedures, with the aim of reducing SSIs. Topical antibiotics applied to surgical wounds healing by primary intention can reduce the risk of SSI relative to no antibiotic, and relative to topical antiseptics, but there is little evidence regarding the effects of topical antibiotics on adverse outcomes such as allergic contact dermatitis. The relative effects of topical antibiotics remain unclear.

The following precautions can help minimize the risk of developing surgical site infections in at-risk patients:

  • Administer pre-operative prophylactic antibiotics, and discontinue use within 24 hours after the procedure.
  • Do not shave the area. If hair removal is absolutely necessary, use single-patient use clippers.
  • Wash and clean the skin around the incision site with a dual agent skin preparation containing alcohol (unless contraindicated).
  • Use an appropriate antiseptic agent for pre-operative surgical scrub, scrubbing the hands and forearms for two to five minutes for most products.
  • Consider the use of nutritional support products for underweight patients who undergo major surgical operations.
  • Antimicrobial dressings may be used to help prevent


CDC. Frequently Asked Questions About Surgical Site Infections. Centers for Disease Control and Prevention. Updated December 14, 2010. Accessed May 9, 2017.

John Hopkins Medicine. Surgical Site Infections. John Hopkins Medicine.…. Accessed May 9, 2017.

Pear, Suzanne M. Patient Risk Factors and Best Practices for Surgical Site Infection Prevention. Halyard Health.…. Published March 2007. Accessed May 9, 2017.

Uçkay I, Harbarth S, Peter R, Lew D, Hoffmeyer P, Pittet D. Preventing Surgical Site Infections. Medscape. Published 2010. Accessed May 9, 2017.

Safe Care Campaign. Surgical Site Infection Educational Media. Safe Care Campaign. Accessed May 9, 2017.

Dumville J, Gray T, Walter C, Sharp C, Page T. Dressings For The Prevention of Surgical Site Infection. Cochrane Library. Published September 1, 2014. Accessed May 23, 2017.

World Health Organization. WHO Global Guidelines for the Prevention of Surgical Site Infection. WHO. Published 2016. Accessed May, 23, 2017.

Singhal, Hemant. Wound Infection Treatment and Management. Medscape. Updated May 5, 2017. Accessed May 23, 2017.

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World Health Organization. Global Guidelines for the Prevention of Surgical Site Infection. World Health Organization.…. Accessed July 12, 2017.