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 need 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 from 1979 to 2000, and sepsis remains the tenth 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; up to 40% of patients with severe sepsis and 60% of patients with septic shock die due to sepsis-related complications (Table 138-1).
Table 138-1 Sepsis Syndromes, Definitions, and Mortality Risk ||Download (.pdf)
Table 138-1 Sepsis Syndromes, Definitions, and Mortality Risk
|Systemic inflammatory response syndrome (SIRS)||At least two of the following four clinical features:
Temperature > 38 degrees Celsius or < 36 degrees Celsius
Heart rate > 90 beats/minute
Respiratory rate > 20 breaths/minute 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)
- Cardiac dysfunction
- Renal dysfunction
- Hepatic dysfunction
- 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%|
Successful shock resuscitation may 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 138-2). An uncontrolled hyperinflammatory response is believed to be the cause of multiple organ dysfunction.
Table 138-2 Correlation between Organ Failure and Mortality in Sepsis ||Download (.pdf)
Table 138-2 Correlation between Organ Failure and Mortality in Sepsis
|One lasting more than one day||20%|
|Two lasting more than one day||40%|
|Three lasting more than three days||80%|