Sepsis

• Sepsis


  Evidence of infection plus life-threatening organ dysfunction, clinically codified by an acute change in 2 points or greater in the SOFA score
• Septic shock


  Sepsis with fluid, unresponsive hypotension, serum lactate level greater than 2 mmol/L, and the need for vasopressors to maintain mean arterial pressure of 65 mm Hg or greater
• Systemic Inflammatory Response Syndrome (SIRS)

  • A group of physiological and immune mediated reactions that are triggered in response to an infectious/ non infectious insult
  • Diagnosed if ≥ 2 of the following 4 criteria are present: Temp: > 38 or < 36, Heart Rate: >90 /min, Respiratory rate: > 20 /min or PaCO2 < 32 mmHg, White blood cell: > 12000 /mm3, < 4000 /mm3
• Sepsis


  SIRS criteria PLUS a suspected or confirmed underlying infection
• Pathophysiology of Sepsis


  1. Infection stimulates normal release of inflammatory mediators

  2. In sepsis, this process becomes self stimulating: Further release of inflammatory mediators

  3. Recruitment of lymphocytes, macrophages and PMNs

  4. Destruction of healthy tissue by immune system

  5. Loss of normal homeostasis is a major contributor to organ failure
• Signs and symptoms of sepsis

  • Fever, chills, and diaphoresis
  • Tachycardia
  • Tachypnea
  • Generalized edema (capillary leak)
  • Features of organ dysfunction (see SOFA score)
  • CNS impairment: altered mental status
  • Cardiovascular failure: hypotension
  • Coagulopathy disseminated intravascular coagulation-petechiae, purpura
  • Liver failure: jaundice
  • Kidney failure: oliguria
  • Respiratory failure; : symptoms of acute respiratory distress syndrome (ARDS)
• Features of septic shock

  • Hypotension (MAP< 65 mm Hg)
  • Altered skin and soft tissue perfusion
  • Early presentation: warm skin and normal capillary refill time (warm shock)
  • Late presentation: cold, cyanotic, pale, and/or mottled skin and prolonged capillary refill time (cold shock)
• qSOFA score


  • Altered mental status (GCS <15)
  • RR > 22
  • SBP < 100
• Management plan for patients with sepsis

  1. Perform diagnostics and treatment simultaneously

  2. Sepsis surveillance: Use a sepsis screening tool to identify at-risk patients

  3. Initial evaluation: Perform a clinical evaluation using the ABCDE approach, establish IV access, continuous cardiac monitoring, and continuous pulse oximetry

  4. Initial studies: Serum lactate, two sets of blood cultures (aerobic and anaerobic) prior to antibiotics

  5. Initial management: Provide immediate hemodynamic support and respiratory support for unstable patients, fluid resuscitation, vasopressors for septic shock, antibiotics for sepsis
• The Sepsis Six


  • Give oxygen to maintain SpO2>94%
  • Take blood cultures
  • Give broad-spectrum intravenous antibiotics
  • Give a fluid challenge
  • Measure lactate
  • Measure urine output and chart hourly fluid balance
• Management of a suspected septic patient

  1. General investigations: Bloods (FBC, UBE, LFTs, CRP, Lactate, Glucose, Coagulation), Urine (Leucocyte esterase, Culture), Arterial blood gas, Imaging (X-ray, Ultrasound, CT/MRI, Echo, PET)

  2. Bacteriological: Blood culture, Specific site culture (e.g. CSF)

  3. Assess for evidence of organ dysfunction using qSOFA and SOFA score

  4. If qSOFA ≥2 and SOFA ≥2, diagnose sepsis

  5. If despite adequate fluid resuscitation, vasopressors required to maintain MAP ≥65mmHg and serum lactate >2mmol/L, diagnose septic shock