What are the criteria for diagnosing Sepsis (Systemic Inflammatory Response Syndrome)?

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From the Guidelines

Sepsis is diagnosed using the Sequential Organ Failure Assessment (SOFA) score or the quick SOFA (qSOFA) criteria, with sepsis defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection, as per the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) 1. The SOFA score assesses six organ systems (respiratory, cardiovascular, hepatic, coagulation, renal, and neurological) with scores ranging from 0-4 for each system. An acute increase in SOFA score of 2 or more points indicates organ dysfunction.

  • For rapid bedside assessment, qSOFA requires at least two of the following:
    • respiratory rate ≥22 breaths/minute
    • altered mental status
    • systolic blood pressure ≤100 mmHg Septic shock is identified when sepsis is accompanied by persistent hypotension requiring vasopressors to maintain MAP ≥65 mmHg and serum lactate >2 mmol/L despite adequate fluid resuscitation 1. Early recognition is crucial as mortality increases with delayed treatment.
  • The key factors in the effective treatment of sepsis include:
    • prompt diagnosis
    • adequate resuscitation
    • early initiation of appropriate antibiotic therapy
    • early and effective source control
    • reassessment of the clinical response and appropriate adjustment of the management strategy 1 The older SIRS criteria are less specific but still used in some settings.
  • Prompt identification and treatment with appropriate antibiotics and supportive care significantly improve outcomes in sepsis patients, with the goal of restoring a mean arterial pressure of 65 to 70 mmHg as a good initial goal during hemodynamic support of patients with sepsis 1.

From the Research

Sepsis Criteria and Treatment

  • Sepsis is a medical emergency and life-threatening condition due to a dysregulated host response to infection, which is time-dependent and associated with unacceptably high mortality 2.
  • The treatment of sepsis involves the initiation of broad-spectrum antimicrobials within the first hour of diagnosis, and optimizing antibiotic use is essential to ensure successful outcomes and to reduce adverse antibiotic effects, as well as preventing drug resistance 2.

Antibiotic Treatment

  • The principle of individualized dosing should replace the principle of standard dosing, and the loading dose is an initial higher dose of an antibiotic for all patients, yet an individualized treatment approach for further doses should be implemented according to pharmacokinetics (PK)/pharmacodynamics (PD) and the presence of renal/liver dysfunction 2.
  • Extended or continuous infusion of beta-lactams and therapeutic drug monitoring (TDM) can help to achieve therapeutic levels of antimicrobials, and reevaluation of duration and appropriateness of treatment at regular intervals are also necessary 2.
  • Meropenem is a commonly used antibiotic for the treatment of sepsis, and its dosing regimen can vary depending on the patient's condition, such as renal function and the presence of septic shock 3, 4, 5.

Oxygen Therapy

  • Liberal oxygen therapy has been a cornerstone in the treatment of critically ill patients, but awareness of hyperoxia toxicity has emerged, and titration of oxygen therapy to normoxia in the emergency department should be evaluated 6.
  • A reduced inspired oxygen fraction of 0.4 instead of 0.6-0.8 can be used to treat sepsis patients in the emergency department, and most patients can achieve a partial pressure of oxygen in arterial blood (PaO2) greater than 9.5 kPa with 10 l O2/min 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

An approach to antibiotic treatment in patients with sepsis.

Journal of thoracic disease, 2020

Research

Clinical outcomes of continuous vs intermittent meropenem infusion for the treatment of sepsis: A systematic review and meta-analysis.

Advances in clinical and experimental medicine : official organ Wroclaw Medical University, 2020

Research

Maximally effective dosing regimens of meropenem in patients with septic shock.

The Journal of antimicrobial chemotherapy, 2018

Research

Oxygen therapy for sepsis patients in the emergency department: a little less?

European journal of emergency medicine : official journal of the European Society for Emergency Medicine, 2014

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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