Lavage by laparoscopy fares better than lavage by laparotomy - Experimental evidence

Background: Although carbon dioxide (CO2) pneumoperitoneum is proposed incr easingly for treatment of secondary peritonitis, associated deleterious eff ects have been reported in experimental models, with the hypothesis that in creased intraperitoneal pressure might facilitate bacterial translocation. The purpose of this study was to compare the outcome (and qualitative micro biologic analysis) from peritonitis in rats after lavage by laparoscopy wit h the outcome after lavage by laparotomy. Methods: After determination of the standard innoculum for this study in 30 animals, 120 male Wistar rats received 1 mi of Escherichi coli 10(6) colon y-forming unit (CFU), Bacteroides fragilis 10(7) CFU, Enterococcus faecalis 10(7) CFU in a sterile rat feces-barium sulfate suspension adjuvant, were anesthetized with intramuscular ketamine, and then underwent peritoneal lav age by either laparotomy (n = 60) or laparoscopy (n = 60). The duration of peritonitis defined two groups: group A: duration less than 3 h (n = 20) an d group B: duration 3 h or more (n = 40). Both groups underwent successive lavage with IO-ml aliquots (total, 50 mi) of 0.9% saline solution at 37 deg reesC. Five 2-ml samples of liquid lavage were drawn for culture and microb iologic analysis. Blood (0.2 mi) and peritoneal liquid lavage samples were incubated 48 h at 37 degreesC and cultured. Results: All the animals survived. Mean duration of peritoneal lavage was 1 3.2 min (range, 6-25 min) for laparoscopy and 9.7 min (range, 6-15 min) and for laparotomy. The difference was not statistically significant. The mean duration of operation was significantly longer with laparoscopy than with laparotomy: 44.5 min (range, 35-62 min) and 25 min (range, 16-40 min), resp ectively (p = 0.0001). The collected lavage volumes were not statistically different: 48.5 mi (range, 40-54 mi) and 46.7 mi (range, 37-56 mi), respect ively. No statistically significant differences were found between the lapa roscopy and laparotomy groups in terms of E. coli bacteremia, irrespective of peritonitis duration. The rates of positive blood culture for B. fragili s and E. faecalis were signficantly lower after laparoscopy than after lapa rotomy, both in the overall group (p = 0.025 and p = 0.045, respectively) a nd when duration of peritonitis exceeded 3 h (p = 0.001 and p = 0.044, resp ectively). Conclusions: In this animal model of secondary peritonitis, lavage by lapar oscopy was associated with less bacteremia for B. fragilis and E. faecalis than peritoneal lavage by laparotomy.