Table 1

Definition of the wound classes

Wound classDefinition
Class I (clean)An uninfected operative wound in which no inflammation is encountered and the respiratory, alimentary, genital or uninfected urinary tracts are not entered.
Class II (clean-contaminated)Operative wounds in which the respiratory, alimentary, genital or urinary tracts are entered under controlled conditions and without unusual contamination.
Class III (contaminated)Includes open, fresh and accidental wounds.
Class IV (dirty-contaminated)Includes old traumatic wounds with retained devitalised tissue and those that involve existing clinical infection or perforated viscera.