Box 1.

American College of Surgeons National Surgical Quality Improvement Program (NSQIP) surgical site infection (SSI) definitions

Superficial incisional SSIa

1) Purulent incisional drainage from above the fascia

2) Organisms isolated from an aseptically obtained culture of fluid or tissue from the superficial incision

3) Pain/tenderness, wound swelling, redness, or heat, and the superficial incision is deliberately opened by the surgeon (unless its culture is negative for organisms)

Deep incisional SSIb

1) Purulent drainage from the deep incision

2) Spontaneous dehiscence or deliberate opening of the fascia in the setting of fever or localized pain/tenderness (unless it is culture negative)

3) An abscess is found involving the deep incision through physical examination, reoperation, or radiologic examination

Organ/space SSI

1) Purulent drainage from an intraperitoneal drain

2) Presence of organisms in culture of fluid obtained aseptically from an organ or space

3) Abscess or other infection involving an organ or space on physical examination, reoperation, or histopathologic or radiologic examination

^aSurgeon diagnosis of any of the 3 types of SSI also meets NSQIP criteria.

^bInvolves deep soft tissues, such as the fascia or muscle layers of the incision.