Research for infection protection

Surgical Site Infection

Nosocomial surgical site infections (SSI) are a problem for all surgical specialties and rank among the most common nosocomial infections in several countries, for example Germany*.To ensure consistent diagnosis of the different surgical site infections, e.g. for surveillance, the CDC case definitions are used**:

A1 Superficial incisional SSI

The infection at the incision area occurs within 30 days after the operative procedure and involves only skin or subcutaneous tissue. In addition, the infection must meet one of the following criteria:

  1. Purulent discharge from the superficial incision.

  2. Microorganism isolated from an aseptically obtained culture of fluid or tissue from the superficial incision.

  3. One of the following signs of infection: pain or tenderness, localized swelling, redness, or heat,

    and

    The superficial incision is deliberately opened by the surgeon. This criterion does not apply when the microbiological culture from the superficial incision tested negative.

  4. Diagnosis by the attending physician.

A2 Deep incisional SSI

The infection occurs within 30 days after the operative procedure (within one year if implant is in place) and appears to be related to the operative procedure involvingfascia and muscle tissue. In addition, the infection must meet one of the following criteria:

  1. Purulent discharge from the deep incision but not from the organ or cavity (these infections belong to category A3).

  2. The deep incision spontaneously dehisces or is deliberately opened by a surgeon, when the patient exhibits at least one of the following symptoms: fever (>38°C), localized pain, or tenderness. (This criterion does not apply when the microbiological culture from the deep incision tested negative).

  3. An abscess or other evidence of infection involving the deep layers is found on direct examination, during reoperation, or by histopathologic or radiologic examination.

  4. Diagnosis by the attending physician.

A3 Organ and cavity SSI

The infection meets all criteria of category A2 and at least one of the following:

  1. Purulent discharge from a drain that is placed into the organ or cavity.

  2. Microorganism isolated from an aseptically obtained culture of fluid (and wound swab respectively) or tissue from the organ or cavity.

  3. An abscess or other evidence of infection involving the organ or cavity is found on direct examination, during reoperation, or by histopathologic or radiologic examination.

  4. Diagnosis by the attending physician.


There are a number of preventive measures that have been proven by evidence:

Recommendations of the Robert Koch-Institute:


* According to data of the German Hospital Infection Surveillance System (KISS = Krankenhaus-Infektions-Surveillance-System); Geffers 2011

**7th edition of the definitions of nosocomial infection (CDC definitions). Robert Koch-Institute, 10 February 2011