PERIOPERATIVE IMMUNE MODULATION

Background. The effects of operative trauma on systemic immunity were studied. The relative effects of skin incision and of breaching the pe ritoneum were determined. In addition, the role of the antiendotoxic a gent taurolidine in preventing postoperative immune suppression was as sessed. Methods. Systemic immune responsiveness was measured as the de layed-type hypersensitivity (DTH) response to 2-4 dinitro l-fluorobenz ene (DNFB) with an an vivo rat model. The effect of both laparotomy an d taurolidine on the hepatic Kupffer cell population was determined by immunohistochemistry. Results. This study confirmed that cellular imm unity is significantly depressed after laparotomy (15.5%; range, 2.5%- 24.0%) compared with unoperated controls (26.77%; range, 9.2%-38.0%). Opening the peritoneum appeared to be a critical factor in inducing th is immunosupression, in which animals undergoing a similar midline inc ision without opening of the peritoneum displayed minimal alteration i n their DTH response (20.5%; range, 0.85%-41.5%). In addition, intrape ritoneal administration of taurolidine in the perioperative period pre vented this decrease in postoperative DTH response. Kupffer cell numbe rs were increased after- intraperitoneal administration of taurolidine , compared with animals treated with intraperitoneal saline solution o r unoperated controls. Conclusions. These findings confirm the presenc e of an operatively induced decrease in immune responsiveness and sugg est that entering the peritoneum is an important factor in the inducti on of this effect. In addition, administration of taurolidine acts to prevent the impact of laparotomy on DTH response, possibly by preventi ng perioperative portal endotoxemia.