Sepsis is a clinical syndrome that complicates severe infection and is characterized by the systemic inflammatory response syndrome (SIRS), immune dysregulation, microcirculatory derangements, and end-organ dysfunction.

The Multiple Organ Dysfunction Syndrome (MODS) can be defined as the development of potentially reversible physiologic derangement involving two or more organ systems not involved in the disorder that resulted in ICU admission, and arising in the wake of a potentially life-threatening physiologic insult.

Sepsis is a clinical syndrome that complicates severe infection and is characterized by the systemic inflammatory response syndrome (SIRS), immune dysregulation, microcirculatory derangements, and end-organ dysfunction. In this syndrome, tissues remote from the original insult display the cardinal signs of inflammation, including vasodilation, increased microvascular permeability, and leukocyte accumulation.

Although inflammation is an essential host response, the onset and progression of sepsis center upon a “dysregulation” of the normal response, usually with an increase in both proinflammatory and antiinflammatory mediators, initiating a chain of events that leads to widespread tissue injury. Evidence supports a state of acquired immune suppression or immunoparalysis in some patients, which may occur simultaneously with or following the initial proinflammatory response. It is this dysregulated host response rather than the primary infectious microorganism that is typically responsible for multiple organ failure and adverse outcomes in sepsis.