Cecal Ligation and Puncture as a Model of Sepsis in the Rat: Influence of the Puncture Size on Mortality, Bacteremia, Endotoxemia and Tumor Necrosis Factor Alpha Levels

Background: Cecal ligation and puncture is a widely used experimental model of sepsis. Aim of the Study: The present study was aimed to evaluate the influence of the size of the cecal puncture on mortality, bacteremia, endotoxemia and plasma TNF-α levels. Materials and Methods: Female Sprague-Dawley rats underwent cecal ligation and puncture, divided into the following groups, defined by the diameter of the cecal puncture: 0.5-cm blade incision (n = 25), 13-gauge (n = 25), 16-gauge (n = 25), 18-gauge puncture (n = 25) and 4 punctures with a 22-gauge needle (n = 25). A sham operation was performed in another 25 rats. Three animals of each group were sacrificed 5 h after the procedure for blood cultures as well as determination of plasma endotoxin and TNF-α. The remaining animals were followed up for a week after cecal ligation and puncture for evaluation of mortality. Results: Five hours after cecal ligation and puncture, bacteremia was present in all animals, independently of the puncture size. Endotoxemia and plasma TNF levels tended to increase along with the diameter of the cecal puncture. Mortality gradually increased with the puncture size, from 27% with a 22-gauge needle to 95% with the blade incision. Conclusions: The severity of sepsis obtained with cecal ligation and puncture in rats can be easily modulated varying the size of the puncture.