NETs are composed of DNA, chromatin and serine proteases. NETs can both destroy extracellular organisms without phagocytosis, and act as a physical barrier to selleck chemicals prevent the further spread of pathogens[17]. Finally, tissue factor, expressed by injured tissue, leads to activation of the coagulation cascade.

This results in increased fibrin production, necessary to contain bacteria by abscess formation. These cellular processes can also have systemic effects, as the products of mast cell degranulation at the site of injury move into the circulatory system. There, in addition to increased vascular permeability, they cause smooth muscle relaxation and can result in peripheral vascular collapse. Free radicals released with degranulation cause lipid peroxidation of cell membranes resulting in further release of toxic granulation products. Granulocytes and macrophages, attracted to the site of injury by the complement chemotactic factors C3a and C5a,

release acute phase cytokines such as IL-1, IL-6, TNF-α, IFN-γ. These cytokines are released into the peripheral circulation where they cause fever, cortisol release, acute phase protein synthesis, leukocytosis, and see more lymphocyte differentiation and activation. The resultant physiologic state is clinically known as the Systemic Inflammatory Response Syndrome (SIRS). SIRS is defined by the very presence of at least two of the following: core body temperature > 38°C or < 36°C, heart rate > 90 beats per minute, respiratory rate > 20 breaths per minute (not ventilated) or PaCO2 < 32 mmHg (ventilated), WBC > 12,000, < 4,000, or > 10% immature forms (bands)[18]. When SIRS is associated with a bacterial source, as with cases

of IAI, it is known as sepsis. When sepsis is paired with organ failure, it is known as severe sepsis. Management Management of IAI requires resuscitation, source control, and antibacterial treatment. The most important of these factors is source control, which, “”encompasses all measures undertaken to eliminate the source of infection and to control ongoing contamination”"[19]. There are three key components of source control: drainage, debridement, and definitive management. Resuscitation and Support of Organ Systems IAI causes volume depletion by several mechanisms. Nausea, anorexia and ileus lead to a decrease in oral intake, while vomiting and diarrhea increase sensible losses. In addition, ileus with third space losses into the bowel wall and ascites, as well as fever both increase insensible losses. Elevated body temperature leads to both an increase in dermal loss via sweating, and an increase in respiratory loss by causing tachypnea.