SIRS vs Sepsis

 Systemic Inflammatory Response Syndrome (SIRS)

1. Non-specific (infections vs non-infectious)
2. ≥2 of the following:
• Temp >38°C or <36°C
• HR >90 bpm
• RR >20 or PaCO₂ <32 mmHg
• WBC >12,000/mm³, <4,000/mm³, or >10% bands

Sepsis

1. Organ dysfunction due to dysregulated host response to infection.
2. SOFA score increases by ≥2.
3. qSOFA (≥2 indicates high risk):

• Altered mental status (GCS <15)
• RR ≥22/min
• SBP ≤100 mmHg

Severe Sepsis (Obsolete Term in Sepsis-3, 2016)

• Sepsis + tissue hypoperfusion/organ dysfunction.

Septic Shock

• Sepsis + circulatory failure

• Hypotension requiring vasopressors (MAP <65 mmHg).
• Lactate >2 mmol/L 

Management (Surviving Sepsis Campaign Guidelines)

• Early recognition & treatment (within 1 hour)
• IV fluids (30 mL/kg crystalloid in 1st 3 hours)
• Broad-spectrum antibiotics ASAP
• Vasopressors (norepinephrine) if MAP <65 mmHg
• Source control (drain abscesses, remove infected devices)
• Supportive care (oxygenation, ventilation, glycemic control, DVT/stress ulcer prophylaxis)