CDC Surgical Wound Class	Alternative Surgical Wound Class
Class I	Clean - Uninfected wound with no inflammation. Respiratory, alimentary, genital, or uninfected urinary tract is not entered.	Clean wound, healthy host (no history of prior procedure at surgical site)
Class II	Clean/Contaminated – Wound in which respiratory, alimentary, genital, or urinary tracts are entered under controlled conditions and without unusual contamination.	Previous surgery, healthy host (no history of prior infection at surgical site)
Class III	Contaminated – Open fresh/open surgical wounds return to OR, accidental wounds. Gross spillage from GI tract, incisions with acute / nonpurulent inflammation, including necrotic tissue without purulence (dry gangrene).	Compromised host (no history of prior infection at surgical site)
Class IV	Dirty/Infected – Old traumatic wounds with retained devitalized tissue and those that involve existing clinical infection or perforated viscera. Suggests that organisms causing postop infection were present preoperatively.	Previous or active infection at site of surgery