SALINE WOUND IRRIGATION REDUCES THE POSTOPERATIVE INFECTION-RATE IN GUINEA-PIGS

Wound irrigation with saline is widely used alone or together with sys temic antibiotic prophylaxis to prevent postoperative wound infection, This study was aimed to investigate the effect of saline irrigation u pon the bacterial load on wound surfaces and on the wound infection ra te in an animal model, In 16 guinea pigs, two wounds were contaminated with Bacteroides fragilis and Escherichia coli. One wound was irrigat ed with saline, while the other received no prophylaxis. Quantitative wound cultures were performed before and after irrigation, The wound i nfection rate was determined at 10 days, Saline irrigation reduced the aerobic and anaerobic bacterial counts in wound margins, The infectio n rate was also reduced (15/16 nonirrigated vs 6/16 irrigated, P < 0.0 01). High bacterial counts at the end of operation were associated wit h wound infection (P < 0.001), At skin closure, wounds which later bec ame infected harbored fourfold more bacteria than noninfected wounds [ 8.7 (6.4-11.0) vs 2.3 (0.8-3.7) colony-forming units . 10(3) of E. col i/cm(2); P < 0.005], Saline wound irrigation diminishes infection rate in experimental animals by means of a significant reduction of the ba cterial inoculum present at the time Of Skin closure. (C) 1996 Academi c Press, Inc.