Table 1 Criteria for SIRS and Sepsis syndromes (modified from Dellinger et al [57])

Systemic inflammatory response syndrome (SIRS) any two or more of the following criteria

▪ HR>90 bpm

▪ RR>20/min or PaCO₂< 32 mmHg

▪ WCC< 4 × 10⁹ cells/L or > 12 × 10⁹ cells/L or > 10% immature bands 12,000

▪ T>38°C or <36°C

Sepsis

▪ SIRS + proven infection

15%

Severe sepsis

▪ Sepsis + failure of one or more organs

20%

Septic shock

▪ Severe sepsis + cardiovascular failure despite adequate fluid resuscitation (usually SABP <90 mmHg or >40 mmHg from baseline)

45%