sepsis

Question 1

what is sepsis?

Answer 1

life-threatening organ dysfunction due to dysregulated host response to infection

Question 2

what is sepsis triggered by?

Answer 2

infection

Question 3

what differentiates sepsis from infection?

Answer 3

organ dysfunction

Question 4

what causes the organ dysfunction?

Answer 4

overwhelming immune response

Question 5

how is organ dysfunction identified?

Answer 5

acute change in total SOFA score of >_ 2 points

Question 6

what is SOFA?

Answer 6

a tool to clinically characterise px at risk of sepsis (prolonged ICU or death)

Question 7

what is the SOFA criteria?

Answer 7

resp >_ 22 breaths/min
altered mentation (ggow coma scale <15)
systolic bp

Question 8

what is baseline SOFA?

Answer 8

0, unless px has pre-existing organ dysfunction before onset of infection

Question 9

what are the common sites of infection causing sepsis?

Answer 9

lungs
abdomen
bloodstream
urinary system

Question 10

what are the common sources of infection causing sepsis?

Answer 10

gram + bacteria
-staph aureus
gram - bacteria
fungal
-candida
-associated with higher mortality

Question 11

who is more likely to get sepsis?

Answer 11

older people
medically/immune compromised px
cancer
cirrhosis
autoimmunity
HIV/AIDS
organ transplantation
diabetes

Question 12

what inflammatory pathways are activated?

Answer 12

innate immunity
complement system
vascular endothelium
coagulation system
adaptive immunity

Question 13

what is the pathophysiology of sepsis?

Answer 13

body-wide blood clotting and leaky vessels
one or more organs begin to fail
persistent hypotension

Question 14

describe PRRs

Answer 14

pattern recognition receptors
-can be specific to one or more molecules
activated by PAMPs/DAMPs
leads to activation of inflammatory signalling pathways

Question 15

what are PAMPs?

Answer 15

pattern-associated molecular patterns
conserved exogenous (non-self) factors expressed by pathogens
eg LPS, peptidoglycan, nucleic acids

Question 16

what are DAMPs?

Answer 16

damage-associated molecular patterns
endogenous (host) factors released following cell damage
eg heat-shock proteins, nucleus acid

Question 17

what does TNF-alpha coordinate?

Answer 17

local containment of infection, but drives sepsis when released systemically

Question 18

what does TNF-a do?

Answer 18

stimulates expression of:
-adhesion molecules on endothelial cells
-proteins that trigger blood clotting
recruits immune cells to site of infection
prevents pathogen spreading via blood

Question 19

how does systemic release of TNF-a contribute to onset of sepsis and septic shock?

Answer 19

systemic vasodilation
increased vascular permeability
loss of blood pressures
systemic blood clotting of microvasculature

Question 20

what is the hallmark of sepsis?

Answer 20

complement

Question 21

how does complement contribute to sepsis?

Answer 21

activated immediately upon recognition of PAMPs and DAMPs
generation of peptides C3a and C5a
C5a drives immunopathogenesis
potent chemoattractant
further amplifies inflammation
contributes to vasodilation, tissue damage and organ failure

Question 22

why do changes in vascular endothelium occur during sepsis?

Answer 22

response to inflammatory stimuli

-endothelial barrier dysfunction

Question 23

what are the characteristics of a hypercoagulative state?

Answer 23

microvascular thrombi
fibrin deposition
neutrophil extracellular trap
formation
endothelial injury

Question 24

what effect does sepsis have on the coagulation system?

Answer 24

results in a hypercoagulative state

Question 25

what organ systems are commonly affected?

Answer 25

neurological
-altered mental status
pulmonary
-hypoxaemia
-ARDs
cardiovascular
-shock
renal
-oligouria

Question 26

how does sepsis affect adaptive immunity?

Answer 26

excessive inflammation and immune suppression

Question 27

describe excessive inflammation

Answer 27

sustained inflammation causes tissue injury
strong activation of innate immunity via PAMPs and DAMPs
sustained hyperinflammation
activation of complement system, coagulation system and vascular endothelium

Question 28

describe immune suppression

Answer 28

both innate and adaptive immunity
apoptosis of T cells, B cells
dysfunctional DCs
delayed apoptosis of immature dysfunctional neutrophils

Question 29

what are the current treatments for sepsis?

Answer 29

enteral feeding
insulin therapy
urinary catheter
lung protective ventilation
antibiotics
fluids
vasopressors
-norepinephrine
-epinephrine
-vasopressin

Question 30

why is a dental abscess highly infectious?

Answer 30

develop during immune response to acute bacterial infection of pulp space
contain immune cells, dead tissue and live bacteria

Question 31

how are dental abscesses treated?

Answer 31

promptly with excision and drainage
periapical abscesses require root canal or extraction
antibiotics ineffective

Question 32

what can happen if dental abscesses spread?

Answer 32

severe local and systemic consequences

Question 33

what are red flag signs and symptoms of spreading dental infection?

Answer 33

temp < 36 or > 38
elevated breathing rate (>20 breaths/min)
elevated or reduced HR
varying degrees of facial swelling
trismus
dehydration