INCREASED SYSTEMIC INFLAMMATION AFTER LAPAROTOMY VS LAPAROSCOPY IN ANANIMAL-MODEL OF PERITONITIS

Objective: To study the influence of laparotomy and laparoscopy on loc al and systemic inflammation in a rat model of peritonitis. Design: Ba cteremia, peripheral leukocyte subpopulations, tumor necrosis factor a lpha (TNF-alpha) plasma levels, and ex vivo secretion of peripheral bl ood mononuclear cells were investigated after laparotomy and laparosco py in a prospective randomized experimental study. Setting: Surgical d epartment of a university hospital. Animals: 60 male inbred Wistar rat s. Interventions: Standardized fecal inoculum was injected intraperito neally and rats underwent laparotomy (n=20), laparoscopy (n=20), or no further manipulation (control group, n=20). Blood samples were obtain ed during the perioperative course to determine bacteremia, leukocytic subpopulations, TNF-alpha plasma levels, and ex vivo secretion. The n umber of intraperitoneal abscesses was determined in each animal after 1 week. Main Outcome Measure: The hypothesis of the experiment was th at laparoscopy with carbon dioxide leads to an increase of local and s ystemic inflammation in comparison with the laparotomy and control gro ups. Results: One hour after intervention, bacteremia was significantl y higher in the laparotomy and laparoscopy groups compared with the co ntrol group (P=.01). Fecal inoculum caused significant monocytopenia a nd lymphocytopenia in all groups within 1 hour after intervention (P<. 05), with complete recovery on day 2 only in the laparoscopy and contr ol groups. Laparotomy caused a significant increase in TNF-alpha plasm a levels and decrease of ex vivo production of TNF-alpha compared with the other 2 groups (P<.05). Conclusions: Laparotomy and laparoscopy i ncreased the incidence of bacteremia and systemic inflammation in this peritonitis model. The inflammatory response was significantly higher in the laparotomy group compared with the laparoscopy group.