An experimental study on surgical wound contamination from distant infective source in rabbits

Surgical wound infections are usually encountered due to the endogenous rather than the exogenous infective sources. The objective of this study was to evaluate the effect of a distant inoculated infective source on the contamination of surgical wounds. Thirty White New Zealand rabbits divided randomly into three control and three treatment equal groups. In treatment groups 24 hrs before surgical intervention Staphylococcus aureus was injected subcutaneously in right thigh. In model animals, skin and muscles were incised 1 cm to the right of the vertebral column and sutured, immediately. The relative frequency of staphylococcal contamination of tissue specimens at 24 and 48 hrs after surgery in treatment groups were 20% and 60%, respectively. Statistical analysis did not show any significant differences in the rate of contamination between control and treatment groups at aforementioned times (P>0.05). However, comparison at 72 hrs after surgery, showed that the rate of contamination in treatment group is significantly more than control ones (P = 0.004). The presence of S. aureus in wounds of treatment animals at 72 hrs after surgery, suggested that microorganisms lodged in any part of body other than wound region could contaminate it, which could be important in wound healing.