sepsis

Question 1

what are the main causes of sepsis

Answer 1

• caused by anything that triggers your immune system
• 40% caused by e. coli
• can be viral, fungal or bacterial infections
• caused when there is a pathogen fighting any infection in the body

Question 2

how does a blood stream infection cause SIRS

Answer 2

1. peripheral blood mononuclear cells (PBMCs) detect pathogens that have entered the bloodstream using PRRs, complement receptors and Fc receptors
2. PBMcs produce pro-inflammatory cytokines due to the pathogen
3. the cytokine TNFa then binds to receptors on endothelial cells
4. This binding causes the release of nitrous oxide - causing vasodilation, high HR, fever, increased CRP levels

Question 3

how does SIRS then develop into sepsis

Answer 3

1. TNFa activates blood neutrophils which produce further TNFa and neutrophil extracellular traps
2. TNFa also activates the endothelial cells which produce tissue factor and nitrous oxide
3. the TF causes coagulation and NO causes capillary leakages
   - all the damage that this causes then increases the inflammation and the immune response which causes more coagulation, creating more damage etc.

Question 4

how can sepsis lead to septic shock

Answer 4

1. uncontrolled inflammation leading to SIRS
2. increased TF causes localised increase in clotting
3. hypercoagulation
4. depletion of clotting factors
5. increased anti-coagulation
6. vasodilation, oedema, hypoperfusion (also caused by increased TNFa, CXCL8, NO from SIRS
   - these come from anaerobic metabolism using lactic acid

Question 5

how do you get further problems from spesis

Answer 5

• there will be a depletion from the immune system so you run out of inflammatory signals
• your vitals will look more stable
• you have compensatory anti-inflammatory response syndrome

Question 6

how do you get severe secondary infections from sepsis

Answer 6

the immune system is so damaged post sepsis that when you get a secondary illness you can’t fight it off
- treat as if they are septic with a lowered threshold for sepsis

Question 7

what are the sepsis symptoms

Answer 7

• new onset confusion
• rigors
• oliguria
• tachypnoea
• non blanching rash

Question 8

what is SIRS

Answer 8

a wide body response involving inflammatory mediators not always caused by infection

Question 9

what is sepsis

Answer 9

SIRS in the presence of documented or suspected infection with organ dysfunction

Question 10

what is septic shock

Answer 10

a subset of sepsis where particularly profound circulatory, cellular and metabolic abnormalities substantially increase mortality

Question 11

what is compensatory anti-inflammatory response syndrome (CARS)

Answer 11

a body wide suppression of immune responses following overwhelming pathogen exposure

Question 12

what are red flags for sepsis

Answer 12

• BP <90
• pulse >130
• reduced GCS
• purpuric rash
• new O2 demand
• resps >25
• urine output <0.5 for 2 hrs
• mottled cyanotic skin
• chemo in last 6 weeks

Question 13

what is done to confirm sepsis

Answer 13

• white cell count
• CRP
• tissue perfusion
• haemodynamic variable
• kidney function
• liver function
• coagulation variables

Question 14

what is the sepsis six

Answer 14

• maintain oxygen levels and tissue perfusion
• identify the pathogen in blood cultures
• give appropriate antibiotic IV
• give IV fluids to maintain BP
• monitor hypoxia state
• monitor kidney function in urine output