ÎÎClean-contaminated: Operative wounds in which the respiratory,
alimentary, genital, or urinary tracts are entered under controlled
conditions and without unusual contamination.
• Specifically, operations involving the biliary tract, appendix, vagina, and
oropharynx are included in this category, provided no evidence of infection or
major break in technique is encountered.
ÎÎContaminated: Open, fresh, accidental wounds.
• In addition, operations with major breaks in sterile technique (eg, open cardiac
massage) or gross spillage from the gastrointestinal tract, and
• Incisions in which acute, nonpurulent inflammation is encountered are included
in this category.
ÎÎDirty or infected: Includes old traumatic wounds with retained
devitalized tissue and those that involve existing clinical infection or
perforated viscera.
Note: This definition suggests that the organisms causing postoperative infection were
present in the operative field before the operation.
NHSN Criteria for Defining a Surgical Site Infection
ÎÎSuperficial incisional SSI: occurs within 30 days postoperatively and
involves the skin or subcutaneous tissue of the incision and at least
one of the following:
• Purulent drainage from the superficial incision.
• Organisms isolated from an aseptically obtained culture of fluid or tissue from the
superficial incision.
• At least one of the following signs or symptoms of infection: pain or tenderness,
localized swelling, redness, or heat, and the superficial incision is deliberately
opened by a surgeon and is culture-positive or not cultured. A culture-negative
finding does not meet this criterion.
• Diagnosis of superficial incisional SSI by the surgeon or attending physician.
ÎÎDeep incisional SSI: occurs within 30 or 90 daysa after the operative
procedure if no implant is left in place or within 1 year if implant
is in place and the infection appears to be related to the operative
procedure, involves deep soft tissues (eg, fascial and muscle layers)
of the incision, and the patient has at least one of the following:
• Purulent drainage from the deep incision but not from the organ/space
component of the surgical site.
• A deep incision spontaneously dehisces or is deliberately opened by a surgeon and
is culture-positive or not cultured and the patient has at least one of the following
signs or symptoms: fever (>38°C), localized pain or tenderness. A culture-negative
finding does not meet this criterion.
• An abscess or other evidence of infection involving the deep incision is found on direct
examination, during reoperation, or by histopathologic or radiologic examination.
• Diagnosis of a deep incisional SSI by a surgeon or attending physician.
1
