Infection is defined as "a microbial phenomenon characterized by an inflammatory response to the microorganisms or the invasion of normally sterile tissue by those organisms."
Bacteremia is the presence of bacteria within the bloodstream, but this condition does not always lead to SIRS or sepsis . Sepsis is the systemic response to infection and is defined as the presence of SIRS in addition to a documented or presumed infection. Severe sepsis meets the aforementioned criteria and is associated with organ dysfunction, hypoperfusion, or hypotension. (See Etiology, Treatment, and Medication.)
Sepsis-induced hypotension is defined as "the presence of a systolic blood pressure of less than 90 mm Hg or a reduction of more than 40 mm Hg from baseline in the absence of other causes of hypotension." Patients meet the criteria for septic shock if they have persistent hypotension and perfusion abnormalities despite adequate fluid resuscitation. MODS is a state of physiologic derangements in which orga