Calc Function

    • Calcs that help predict probability of a diseaseDiagnosis
    • Subcategory of 'Diagnosis' designed to be very sensitiveRule Out
    • Disease is diagnosed: prognosticate to guide treatmentPrognosis
    • Numerical inputs and outputsFormula
    • Med treatment and moreTreatment
    • Suggested protocolsAlgorithm





    Chief Complaint


    Organ System


    Patent Pending

    SIRS, Sepsis, and Septic Shock Criteria

    Defines the severity of sepsis and septic shock.


    February 2016: These criteria are no longer recommended for the diagnosis of sepsis, as they are neither sufficiently sensitive nor specific. For the latest on sepsis, visit our qSOFA Score or the Sepsis-3 Consensus Definitions.

    For patients under 18, please use the Pediatric SIRS, Sepsis, and Septic Shock Criteria.

    When to Use
    Why Use
    SIRS Criteria (≥ 2 meets SIRS definition)
    Sepsis Criteria (SIRS + Source of Infection)
    Severe Sepsis Criteria (Organ Dysfunction, Hypotension, or Hypoperfusion)
    Septic Shock Criteria
    Multiple Organ Dysfunction Syndrome Criteria


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    Next Steps
    Creator Insights


    • When a patient presents with two or more SIRS criteria but with hemodynamic stability (i.e. blood pressure at baseline), a clinical assessment must be made to determine the possibility of an infectious etiology.
    • If an infection is suspected or confirmed, the patient is diagnosed with Sepsis and a lactate level is obtained to determine the degree of hypoperfusion and inflammation. A lactate level ≥ 4 mmol/L is considered diagnostic for Severe Sepsis, and aggressive management with broad spectrum antibiotics, intravenous fluids, and vasopressors should be initiated (aka EGDT).
    • Patients that present with a suspected or confirmed infection AND hemodynamic instability should immediately be treated for Septic Shock. While SIRS criteria will likely be present in these patients, aggressive management should not be delayed while waiting for laboratory values such as the WBC or lactate.
    • The management of Severe Sepsis and Septic Shock is the topic of intense research and scrutiny.
    • While Early Goal Directed Therapy has been advocated in the Surviving Sepsis Guidelines, there remains controversy as to which of the bundled interventions are necessary.
    • Recent studies have showed EGDT not to be better than “usual care”, and called for significant amendments to currently used sepsis protocols.
    • To date, most experts agree that early recognition of Sepsis, Severe Sepsis, and Septic Shock, and early administration of broad spectrum and organism specific antibiotic are the most critical actions.
    • There remains controversy in the type of fluids that should be used, their quantity, and the timing of vasopressors and/or inotropes.

    Critical Actions

    • Assess all patients presenting with two or more SIRS criteria for the possibility of an infectious etiology.
    • Screen for Severe Sepsis by obtaining a lactate level on patients with Sepsis, that are elderly, immunocompromised, or ill appearing.
    • Some experts recommend obtaining a lactate level on all patients in whom blood cultures are sent. This is institution dependent however and not mandated in any guidelines.
    • When Severe Sepsis or Septic Shock are identified, initiate broad spectrum antibiotics immediately. These antibiotics should be organism specific and therefore institutional antibiograms should be used.
    • The Surviving Sepsis Campaign Guidelines recommend initiation of antimicrobials within one hour from the time of recognition of Severe Sepsis or Septic Shock, or within three hours of the patient’s arrival to the hospital.
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