SEPSIS Flashcards
define colonsation
the presence of a microbe in the human body without an inflammatory response
define infection
inflammation due to a microbe
define bacteraemia
the presence of viable bacteria in the blood
define sepsis
life-threatening organ dysfunction caused by a dysregulated host response to infection
define septic shock
- Subset of sepsis with circulatory and cellular/metabolic dysfunction associated with a higher risk of mortality.
- There must have been adequate attempts at resuscitation
name 4 risk factors for sepsis
- <1 year and >75 years
- recent trauma/surgery or invasive procedure
- impaired immunity due to illness (eg DM) or drugs (eg long term chemo or IS)
- any breach of skin integrity ( eg cut, burn, blister, skin infection), indwelling lines and catheters
correction of hypotension
- fluid resuscitation
- if required inotropes and vasoconstrictors can be used
use of inotropes
- eg nor/adrenaline
- cause vasoconstriction ± increase myocardial contractility
- indicated when there is persistent hypotensiondespite optimized fluid resuscitation/euvolaemia restored
shock liver
- acute liver injury caused by hypoperfusion
- can cause transaminitis (grossly elevated ALT/AST in blood stream) and jaundice due to hepatocyte injury
CNS features of sepsis
- delirium/acute confusional state due to diffuse cerebral hypoperfusion/dysfunction
- drowsiness and decreased conscious level
how can lactic acidosis occur in sepsis
- type A (due to tissue hypoxia)
- diffuse tissue hypoxia results in anaerobic metabolism (lactic acid is the end product of anaerboic metabolism of glucose)
what effect does metabolic acidosis have on CV stability
worsens it
haematological effects of sepsis
- disseminated intravascular coagulation: small clots form throughout the blood stream blocking small blood vessels
- increased clotting decreases platelets and clotting factors needed to control bleeding
evidence of DIC
- low platelets
- prolonged APTT/PT
- low fibrinogen
SIRS criteria
what else can cause SIRS
NO INFECTION - NOT SEPSIS
Can sepsis be caused by viruses
yes
qSOFA score
- identifies high risk patients for in-hospital mortality with suspected infection
- ≥2 qSOFA score and the likelihood of infection is assocated with a greater risk of death/prolonged ITU stay
GCS
<14 needed for qSOFA
NEWS score for sepsis
≥5 and indication of infeciton = SEPSIS
SEPSIS 6 BUNDLE
blood cultures - before or after ABx, and how many
- blood cultures then IV ABx
- sample area of infection in addition to blood cultures eg stool, urine, tissue, wound etc
- one blood culture (set of 2) is enough
how many blood cultures for suspected endocarditis
3 sets of 2, spread over one hour
then ABx
pathology of hypotension in sepsis
- bacteria produce toxins which stimulate the immune system to produce cytokines
- these increase NO production in vascular smooth muscle which is a potent vasodilator
- vasodilation - fall in TPR, fall in BP
- endothelial dysfunction and capillary leak leads to decreased intravascular volume
consequences of hypotension
- results in tissue hypoperfusion
- hypoxia and organ dysfunction
- hypoxia leads to anaerobic metabolism, which produces lactic acid as a by product
- metabolic acidosis with raised anion gap
- deterimental effects
fluid in SEPSIS 6
500ml saline 0.9% STAT (immediately)
serum lactate level
- normal <1.8 mmol/L
- elevation suggests hypoperfusion/hypoxia
- can be used to assess response following treatment
