Sepsis

1. What is the difference between sepsis, septicaemia and septic shock?

2. What are the criteria to diagnose sepsis?

3. What is early direct goal therapy? (EDGT)

1. Systemic Inflammatory Response Syndrome (SIRS)

• Sepsis: SIRS + infection
• Severe sepsis: Sepsis + organ hypoperfusion e.g. hypoxaemia, oliguria, lactic acidosis, altered mental function
• Septic shock: Severe sepsis + hypotension (SBP < 90mmHg) despite adequate fluid resuscitation, or need vasopressor/inotropes to maintain BP
• Septicaemia: Presence of multiplying bacteria in circulation

2. Diagnosis: SIRS need 2 or more of the below criteria:

• HR >90 bpm
• T° >38°C or <36°C
• RR > 20 breaths/min, or PaCO₂ <32mmHg (4.3kPa)
• WBCC > 12 or <4 x 10⁹/L, or >10% immature band forms

Since sepsis = SIRS + infection, we need 2 or more of the above criteria + culture and sensitivity (C+S) result.

• C+S taken before antibiotic treatment
• > 2 blood C+S taken (each 10ml)
• C+S from percutaneous and vascular device in place

3. Early Goal-Directed Therapy (EGDT) is a more specific form of therapy used for the treatment of severe sepsis and septic shock. This approach involves adjustments of cardiac preload, afterload, and contractility to balance oxygen delivery with an increased oxygen demand before surgery. We need to identify hypotension / serum lactate > 4 mmol/l, if either of them present, administer crystalloid.

Initial goal of resuscitation in < 6hr:

• CVP = 8-12 mmHg (12-15 mmHg if on mechanical ventilation)
• MAP > 65 mmHg
• Urine output > 0.5 ml/kg/hr
• ScvO₂  > 70%

CVP = central venous pressure

MAP = mean arterial pressure

ScvO₂  = central venous oxygen saturation