What are the different stages and severity of sepsis, a systemic inflammatory response syndrome (SIRS) caused by infection?

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From the Guidelines

Sepsis is now defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection, and it progresses through stages of increasing severity, including sepsis, and septic shock, with the latter being the most critical stage requiring vasopressors to maintain mean arterial pressure above 65 mmHg. The stages of sepsis can be identified by the following characteristics:

  • Sepsis: a life-threatening organ dysfunction caused by a dysregulated host response to infection, characterized by an increase in the Sequential Organ Failure Assessment (SOFA) score of 2 points or more 1.
  • Septic shock: a subset of sepsis, clinically identified by a vasopressor requirement to maintain a mean arterial pressure of 65 mmHg or greater and serum lactate level greater than 2 mmol/L in the absence of hypovolemia 1. The severity of sepsis can be assessed using the quick SOFA (qSOFA) score, which includes variables such as Glasgow Coma Scale score, systolic blood pressure, and respiratory rate 1. Some key points to consider in the management of sepsis include:
  • Early recognition and prompt administration of intravenous fluids and vasopressors are crucial in the treatment of sepsis 1.
  • The use of broad-spectrum antibiotics, such as carbapenems or extended-range penicillin/β-lactamase inhibitor combinations, is recommended for empiric therapy in sepsis and septic shock 1.
  • The classification of sepsis has been updated to reflect the current understanding of the disease, with a focus on organ dysfunction and the host response to infection 1. It is essential to note that the definition of severe sepsis is now superfluous, and sepsis should be considered a spectrum of disease, ranging from mild to severe, with septic shock being the most critical stage 1.

From the Research

Stages of Sepsis

  • Sepsis: a life-threatening condition that occurs when the body's response to infection causes injury to its own tissues and organs 2, 3, 4
  • Severe sepsis: a subset of sepsis in which there is associated organ dysfunction 3, 4
  • Septic shock: a subset of severe sepsis in which there is persistent hypotension despite adequate fluid resuscitation 2, 3, 4

Severity of Sepsis

  • The severity of sepsis can be quantified using the Sequential Organ Failure Assessment (SOFA) score 5
  • The Quick SOFA (qSOFA) criteria can be used to rapidly identify potentially infected patients at risk for poor outcomes 5
  • The diagnosis of septic shock requires vasopressor dependence and increased lactate levels 5

Clinical Implications

  • Early recognition and treatment of sepsis are essential to reducing organ system injury and mortality 2, 3, 4
  • Delays in antimicrobial administration are associated with rapid increases in likelihood of progression to septic shock 6
  • The qSOFA score has higher specificity than the systemic inflammatory response syndrome (SIRS) score for predicting septic shock, but is associated with a worse outcome, even when patients receive early antibiotics 6

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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