Overview of sepsis Flashcards
What is colonisation?
The presence of a microbe in the human body without an inflammatory response
What is infection?
Inflammation due to a microbe
What is bacteraemia?
Presence of viable bacteria in the blood
What is sepsis?
Life-threatening organ-dysfunction due to dysregulated host response to infection.
What is septic shock?
A subset of sepsis with circulatory and cellular/metabolic dysfunction associated with higher mortality risk.
What is required for septic shock to be present?
Sepsis AND both of:
- Persistent hypotension requiring vasopressors to maintain Mean Arterial Pressure (MAP) greater than or equal to 65 mm Hg,
AND
- Lactate greater than or equal to 2 mmol/l.
(despite adequate volume resuscitation)
What is systemic inflammatory response syndrome (SIRS)?
Systemic inflammatory response syndrome (SIRS) is an exaggerated defense response of the body.
What can SIRS occur in response to and how does the body attempt to compensate?
To a noxious stressor (infection, trauma, surgery, acute inflammation, ischaemia or reperfusion, or malignancy,
To localise and then eliminate the endogenous or exogenous source of the insult.
Features of SIRS?
A non-specific clinical response including >2 of the following:
- Temperature >38oC or <36oC
- Heart rate >90 beats/min
- Respiratory rate >20/min
- White blood cell count >12,000/mm3 or <4,000/mm3 or >10% immature neutrophils
As well as infection, SIRS can also be caused by trauma, burns, pancreatitis and other insults
What is sequence of disease continuum for sepsis?
Infection
SIRS
Sepsis
Septic shock
Death
Sepsis occurs before SIRS. True/false?
False
Sepsis occurs after SIRS
Sepsis = SIRS with a presumed or confirmed infectious process
What is the main feature of septic shock?
Sepsis plus signs of at least one acute organ dysfunction:
- Renal
- Respiratory
- Hepatic
- Haematological [e.g DIC]
- Central nervous system
- Unexplained metabolic acidosis
- Cardiovascular [hypotension]
What is the criteria for SIRS?
SIRS includes >2 of the following:
- Temperature >38oC or <36oC
- Heart rate >90 beats/min
- Respiratory rate >20/min
- White blood cell count >12,000/mm3 or <4,000/mm3 or >10% immature neutrophils
What is sepsis-2 vs sepsis-3?
Sepsis-2 (≥2 systemic inflammatory response syndrome criteria + infection).
Sepsis-3 (prescreening by quick Sequential Organ Failure Assessment [qSOFA]).
What is qSOFA (quick sequential organ failure assessment)?
The third international consensus definition for sepsis and septic shock (sepsis 3), used as a score for detection of patients at risk of sepsis outside of intensive care units.
What is septic shock?
Occurs when the arterial blood pressure drops despite adequate fluid resuscitation, resulting in organ hypoperfusion. Anaerobic respiration begins, and the serum lactate level rises.
It is diagnosed with:
- Low mean arterial pressure (below 65 mmHg) despite fluid resuscitation (requiring vasopressors)
- Raised serum lactate (above 2 mmol/L)
Management of septic shock?
Septic shock requires aggressive treatment with IV fluids to improve blood pressure and tissue perfusion.
Patients should be escalated to high dependency or intensive care for treatment with vasopressors such as noradrenaline.
How do vasopressors help with septic shock?
Vasopressors are medications that cause vasoconstriction (narrowing of blood vessels), increasing systemic vascular resistance and consequently mean arterial pressure (MAP), helping to improve tissue perfusion.
What is SOFA (Sequential Organ Failure Assessment)?
Can be used to assess the severity of organ dysfunction, most often in the intensive care unit.
It takes into account signs of organ dysfunction:
Hypoxia
Increased oxygen requirements
Requiring mechanical ventilation
Low platelets (thrombocytopenia)
Reduced Glasgow Coma Scale (GCS)
Raised bilirubin
Reduced blood pressure
Raised creatinine
Risk factors for sepsis?
Very young or old patients (under 1 or over 75 years)
Chronic conditions, such as COPD and diabetes
Chemotherapy, immunosuppressants or steroids
Surgery, recent trauma or burns
Pregnancy and childbirth
Indwelling medical devices, such as catheters or central lines
What is assessed in the NEWS for sepsis?
Temperature
Heart rate
Respiratory rate
Oxygen saturation
Blood pressure
Consciousness level
Additional signs of infection in sepsis?
Signs of potential sources, such as cellulitis, discharge from a wound, cough or dysuria
Reduced urine output
Mottled skin
Cyanosis
Arrhythmias, such as new-onset atrial fibrillation
A non-blanching rash can indicate meningococcal septicaemia
What is mottled skin?
It occurs when blood flow to tiny vessels under your skin is disrupted. This results in a fine, bluish-red, lace-like pattern
What is an early sign of sepsis?
A raised respiratory rate (tachypnoea) is often an early sign of sepsis
