Table 1.

Experimental models of sepsis

	Non-surgical models of sepsis		Surgical models of sepsis
	Bacteria or endotoxin (LPS) injection	Cecal slurry (CS) injection	Cecal Ligation and Puncture (CLP)	Bacteria and fibrin clot implantation	Colon Ascendens Stent Peritonitis (CASP)
Description	Intraperitoneal or intravenously injection of bacteria or purified LPS	Intraperitoneal injection of cecal contents from a donor	Ligation of a portion of the cecum followed by cecal colostomies via one or more needle punctures	Standardized amounts of bacteria into fibrin clots, implanted into the peritoneal cavity	Insertion of a stent into the ascending colon to allow the stool to continuous flow from the colon into the peritoneal cavity
Pros	- Easy procedure - Replicates the physiology of severe sepsis - Highly reproducible - Dose of bacteria or endotoxin can be standardized	- High reproducibility - No surgical tissue trauma or ischemic tissue - Advantageous in experiments that require large number of animals - Can be performed in neonatal animals with less risk of being neglected by the mother - Standardized polymicrobial inoculum (fix weight-based intraperitoneal fecal injection)	- Easy procedure - Partly reflects human disease - Extensively studied - Sepsis severity can be adjusted based upon the length of the cecum ligated and the size and number of punctures performed - Better to study peritoneal abscess formation, local inflammation and infiltration	- Fibrin delays systemic infection - Replicates features of sepsis in humans - Low early mortality - Highly reproducible	- Mimic human sepsis better than CLP - Better to study bacteremia, SIRS and sepsis - Sepsis severity can be adjusted altering the size of the catheter
Cons	- Transient inflammatory response - Intoxication model (septic shock) - Host response limited to gram negative organisms (LPS) or bacteria injected	- High variability (lethality of the cecal preparation varies between donor batches)	- Surgical trauma - Time consuming - Bacterial dissemination in the peritoneum (more localized inflammation) - High variability - Impossible to control rate and amount of fecal material released	- Surgical trauma - The use of a single organism in the fibrin clot does not have clinical relevance	- Time consuming - Low characterized - High variability