Sepsis and septic shock are among the leading causes of admission to ICU. This chapter focuses on clinically relevant pathophysiology and its implications for diagnosis and treatment.
Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated response to infection, and septic shock refers to the need for vasopressors to maintain a MAP >65 mmHg with a lactate level >=2 mmol/L. Proinflammatory immune pathways (specifically the activation of the endothelium, cytopathic hypoxia, septic cardiomyopathy and endocrine dysfunction) explain multiorgan failure, which commonly accompanies sepsis, and justify therapeutic interventions.
Early recognition and initiation of therapy are crucial for survival, but diagnosis can be tricky due to its inconsistent clinical picture and lack of specific biomarkers. Initial management should focus on the stabilisation of haemodynamics with balanced crystalloids and vasopressors, early and adequate antibiotic therapy and source control.
When clinical improvement has been achieved, de-escalation of fluid and antibiotic therapy is key to prevent patient harm.