Inhibition of peritonitis by amide local anesthetics

Peritonitis was induced in rats by exposing the peritoneal surface to 0.1 M hydrochloric acid (HCl). Peritonitis was quantified by extraction of Evans blue-bound albumin from the tissue exposed to HCl and analyzed by a spectrophotometric technique. In the first set of experiments, one group of rats had the peritoneal surface exposed to HCl following local pretreatment with isotonic saline; a second group of rats had the peritoneum exposed to HCl after topical pretreatment with an equal volume of lidocaine 1%, whereas in a third group the peritoneal surface was exposed only to saline without HCl. The experimental design in the second set of experiments was similar to that of the first set except that bupivacaine 0.5% was used instead of lidocaine in the second group. Results show a significant inhibition of peritonitis in the groups pretreated with lidocaine (P less than 0.01) and bupivacaine (P less than 0.05) compared with rats in the saline pretreated group. In the lidocaine-pretreated group Evans blue-albumin extravasation did not differ significantly from the rats not receiving HCl, whereas the bupivacaine-pretreated group showed a slightly but significantly (P less than 0.05) more pronounced peritonitis than control rats not exposed to HCl. In the third set of experiments the peritoneum was topically treated with either lidocaine 1%, bupivacaine 0.5%, or isotonic saline after first having exposed the peritoneal surface to HCl. A significant inhibition of albumin extravasation was seen following lidocaine (P less than 0.001) or bupivacaine (P less than 0.001) treatment compared with treatment with isotonic saline.(ABSTRACT TRUNCATED AT 250 WORDS)