Key Clinical Questions
What is the definition of systemic inflammatory response syndrome (SIRS) and how do you differentiate SIRS from sepsis, severe sepsis, and septic shock?
Which patients presenting with sepsis need admission to the intensive care unit (ICU)?
Which septic patients require invasive monitoring (arterial catheter, central venous catheter)?
What interventions in the treatment of sepsis improve mortality?
Which septic patients deserve empiric steroids as part of the therapeutic regimen?
Sepsis is a clinical syndrome that complicates severe infection and is characterized by systemic inflammation and widespread tissue injury. The incidence and number of sepsis-related deaths has increased yearly from 1979 to 2009 with a combined peak of both primary and secondary sepsis in 2009 greater than 1 million patients in the United States; and sepsis is the ninth most common cause of death in the United States. Despite the rising number of cases, earlier identification of sepsis and improved intensive medical care has been shown to reduce the overall mortality rate to approximately 17.9%. Severity is correlated with mortality (Table 141-1).
TABLE 141-1Sepsis Syndromes, Definitions, and Mortality Risk ||Download (.pdf) TABLE 141-1 Sepsis Syndromes, Definitions, and Mortality Risk
|Syndrome ||Definition ||Approximate Mortality |
|Systemic inflammatory response syndrome (SIRS) || |
At least two of the following four clinical features:
Temperature >38°C or <36°C
Heart rate >90 beats/min
Respiratory rate >20 breaths/min or PaCO2 <32 mm Hg
White blood cell (WBC) count >12,000 cells/mm3, or <4000 cells/mm3, or >10% immature (band) forms
|Sepsis ||SIRS criteria plus a culture-proven infection or presumed presence of an infection ||20% |
|Severe sepsis || |
Sepsis plus presence of one or more organ dysfunctions including:
Pulmonary dysfunction (eg, acute respiratory distress syndrome)
Neurologic dysfunction (altered sensorium)
Hematologic dysfunction (eg, disseminated intravascular coagulation [DIC], thrombocytopenia)
Lactic acidosis (indicating end-organ hypoperfusion)
|Septic shock ||Sepsis and refractory hypotension with mean systemic blood pressure lower than 65 mm Hg unresponsive to crystalloid fluid challenge of 20-40 cc/kg ||40%-60% |
Initially successful shock resuscitation may still be associated with considerable morbidity and mortality. Multiple organ dysfunction syndrome (MODS) refers to severe acquired dysfunction of at least two organ systems lasting at least 24 to 48 hours in the setting of sepsis, trauma, burns, or severe inflammatory conditions so that homeostasis cannot be maintained without intervention. Mortality is directly correlated with the number of dysfunctional organs and the duration of dysfunction (Table 141-2). An uncontrolled hyperinflammatory response is believed to be the cause of multiple organ dysfunction.
TABLE 141-2Correlation between Organ Failure and Mortality in Sepsis ||Download (.pdf) TABLE 141-2 Correlation between Organ Failure and Mortality in Sepsis
|Organ Failure ||Mortality |
|One organ lasting more than 1 d ||20% |
|Two organs lasting more than 1 d ||40% |
|Three organs lasting more than ...|