Important Definitions in Sepsis

Dr Rosalind O’Reilly

Overview

• Origins of definitions• Infection• Bacteraemia• Systemic Inflammatory Response Syndrome• Sepsis• Severe Sepsis• Multi Organ Dysfunction Syndrome

Origin of Definitions

• Initially defined in 1991 – Consensus panel convened by ACCP and SSCM

• Reconsidered in 2001 International Sepsis Definitions Conference– ACCP, SCCM, ATS, ESICM, SIS

• Reconsidered again 2012– SSCM and ESICM

INFECTION

Invasionof

normally sterile tissue by

organisms

BACTERAEMIA

presence of

viable bacteria in

blood

SYSTEMIC INFLAMMATORY RESPONSE SYNDROME

clinical syndrome from

dysregulated inflammatory response to

noninfectious insult

SEPSIS

Infection +

systemic manifestations of infection

Systemic Manifestations

• General variables– Temp >38.3 °C <36 °C– HR >90 /min– Tachypnoea– Altered mental status– Significant oedema or

positive fluid balance >20mL/kg over 24hr

– Hyperglycaemia >7.7mmol/L in absence of diabetes

• Inflammatory variables– WCC >12, <4 x109/L– Normal WCC

>10%immature– CRP > 2SD – Procalcitonin >2SD

• Haemodynamic variables– SBP <90mmHg or decrease

>40mmHg– MAP <70mmHg

Systemic Manifestations

• Organ dysfunction– Arterial hypoxaemia

(PaO2/FiO2 <40kPa / 300mmHg)

– Acute oliguria (urine output <0.5mL/kg/hr for at least 2 hrs despite adequate fluid resuscitation)

– Creatinine increase 44.2μmol/L

– Coagulation abnormalities (INR >1.5 or APTT >60s)

– Ileus (absent bowels sounds)

– Thrombocytopenia (plt <100 x103/mm3)

– Hyperbilirubinaemia

• Tissue perfusion variables– Hyperlactatemia

>1mmol/L– Decreased capillary refill

or mottling

SEVERE SEPSIS

Sepsis +

sepsis-induced organ dysfunction or

tissue hypoperfusion

Tissue hypoperfusion or organ dysfunction

• Sepsis-induced hypotension• Lactate above upper limits• Urine output < 0.5mL/kg/hr for more than 2 hrs despite adequate

fluid resuscitation• Acute lung injury with PaO2/FiO2 < 33kPa (250mmHg) in the absence

of pneumonia as infection or source• Acute lung injury with PaO2/FiO2 in the presence of pneumonia as

infection source• Creatinine > 176.8 μmol/L• Bilirubin >32 μmol/L• Platelet count <100 x109 /mm3

• Coagulopathy (PT or APTT > 1.5 x control)

SEPTIC SHOCK

Sepsis-induced hypotension persisting

despite adequate fluid resuscitation

MULTI ORGAN DYSFUNCTION SYNDROME

Progressive organ dysfunction+

homeostasis cannot be maintained without intervention

MODS

• PRIMARY– well-defined insult– early organ dysfunction– directly attributable

• SECONDARY– organ failure not in

direct response to the insult

– is a consequence of the host’s response

MODS

• No universally accepted criteria for individual organ dysfunction in MODS

• Progressive abnormalities of – PaO2/FiO2 ratio– Platelet count– Serum bilirubin – Serum creatinine– Glasgow coma score– Hypotension

Questions???