Sepsis and Septic Shock

Question 1

SIRS criteria

Answer 1

temp <36 or >38
HR > 90
RR > 22 or PaCO2 <32
WBC >12,000 or <4,000 or 10% bands

Question 2

sepsis =

Answer 2

SIRS + infection

Question 3

severe sepsis =

Answer 3

sepsis + end organ damage

Question 4

septic shock =

Answer 4

severe sepsis + hypotension

Question 5

sepsis definition

Answer 5

life threatening organ dysfunction caused by dysregulated host response to infection

Question 6

how can organ dysfuction be identified?

Answer 6

acute change in total SOFA score > 2 points consequent ot the infection

Question 7

how can septic shock be identified?

Answer 7

Septic shock can be identified with a clinical construct of sepsis with persisting hypotension requiring vasopressors to maintain MAP > 65 mmHg and having a serum lactate of >2 mmol/l despite adequatevolume resuscitation.

Question 8

what is the hospital mortality of patients with septic shock?

Answer 8

40%

Question 9

how to calculate SOFA score

Answer 9

hypotension, systolic BP < 100
altered mental status
tachypnoea RR > 22

Question 10

body defence mecahnisms

Answer 10

physical barrier - skin mucosa, epithelial lining
innate immune system - IgA in GIT, dendritic cells/macrophages
adaptive immune system - lymphocytes, immunoglobulins

Question 11

patients with sepsis have an uncontrolled inflammatory response. what features are consistent with immunosuppression?

Answer 11

loss of delayed hypersensitivity
inability to clear infection
predisposition to nosocomial infection

Question 12

change in sepsis syndrome over time

Answer 12

increase in inflammatory mediators then there is a shift to an anti-inflammatory immunosuppressive phase

Question 13

name the 3 phases in the pathogenesis of sepsis

Answer 13

release of bacterial toxins
release of mediators
effects of specific excessive mediators

Question 14

bacterial invasion of the body tissues is a source of what?

Answer 14

dangerous toxins

Question 15

name the commonly released gram negative toxins

Answer 15

lipopolysaccharide (LPS)

Question 16

name the commonly released gram positive toxins

Answer 16

microbial associated molecular pattern: lipoteichoic acid, muramyl dipeptides

super antigens: staphylococcal toxic shock syndrome, streptococcal exotoxins

Question 17

name the 3 components of the release of mediators in sepsis

Answer 17

effects of infections due to endotoxin release
effects of infections due to exotoxin release
mediator role on sepsis (Th1 vs Th2)

Question 18

draw a diagram showing effects of infections due to endotoxin release

Answer 18

LPS needs an LPS-binding protein to bind to macrophages

LTA do not need these

Question 19

draw a diagram to show the effects of infections due to exotoxin release

Answer 19

pro-inflammatory response

small amounts of super antigens will cause a large number of mediators to be secreted: cascade effect

Question 20

what is the mediator role on sepsis?

Answer 20

pro-inflammatory
causes inflammatory response that characterises sepsis
compensatory anti-inflammatory reaction can cause immunoparalysis

Question 21

describe the effects of pro-inflammatory mediators

Answer 21

• Promote endothelial call – leukocyte adhesion
• Release of arachidonic acid metabolites
• Complement activation
• Vasodilatation of blood vessels by NO
• Increase coagulation by release of tissue factors and membrane coagulants
• Cause hyperthermia

Question 22

describe the effects of anti-inflammatory mediators

Answer 22

• Inhibit TNF alpha
• Augment acute phase reaction
• Inhibit activation of coagulation system
• Provide negative feedback mechanisms to pro-inflammatory mediators

Question 23

clinical features of sepsis: nervous system

Answer 23

altered consciousness
confusion
psychosis

Question 24

clinical features of sepsis: respiratory

Answer 24

tachypneoa
PaO2 <70
<90%

Question 25

clinical features of sepsis: liver

Answer 25

jaundice increased liver enzymes decreased albumin increased prothrombin

Question 26

clinical features of sepsis: blood

Answer 26

decreased plateletes increased PT/APTT decreased protein C increased d-dimer

Question 27

clinical features of sepsis: cardiac

Answer 27

tachycardia | hypotension

Question 28

clinical features of sepsis: renal

Answer 28

oliguria anuria increased creatinine

Question 29

clinical features of sepsis: general

Answer 29

fever >38 hypothermia <36 hyperglycaemia > 8 mmol/l

Question 30

inflammatory variables in sepsis

Answer 30

``` leucocytosis WCC > 12,000/ml leucopoenia WCC < 4,000/ml normal WCC with >10% immature high CRP high procalcitonin ```

Question 31

haemodynamic variables in sepsis

Answer 31

arterial hypotension - systolic < 90 or MAP < 70 | SvO2 > 70%

Question 32

organ dysfunction variables in sepsis

Answer 32

``` arterial hypoxaemia PaO2/FiO2 < 50mmHg oliguria < 0.5ml/kg/h creatinine increase coagulation abnormalities PT > 1.5 or APTT > 60s ileus thrombocytopaenia <150,000/ml hyperbilirubinaemia ```

Question 33

tissue perfusion variables in sepsis

Answer 33

high lactate | skin mottling and reduced capillary perfusion

Question 34

how can the host affect sepsis presentation?

Answer 34

• Age • Co-morbidities o COPD, DM, CCF, CRF, disseminated malignancy • Immunosuppression o Acquired – HIV/AIDS o Drug induced – steroids, chemotherapeutic agents, biologics o Congenital – agammaglobulinaemia, phagocytic defects, defects in terminal complement component • Previous surgery – splenectomy

Question 35

how can the organism affect sepsis presentation?

Answer 35

gram positive vs gram negative virulence factors - MRSA, toxin secretion, ESBL, KPC, NDM-1 bioburden

Question 36

how can the environment affect sepsis presentation?

Answer 36

occupation travel hospitalisation

Question 37

sepsis 6

Answer 37

``` high flow oxygen IV antibiotics IV fluids Blood cultures Serum lactate Urine output ```

Question 38

antibiotic guidance in sepsis 6

Answer 38

o Based on working diagnosis from history and examination o Local antibiotic guidelines o Consider allergy o Consider previous MRSA, ESBL, CPE o Consider antibiotic toxicity/interactions

Question 39

IV fluids in sepsis 6

Answer 39

30ml/kg

Question 40

in sepsis, if there is a spike in temperature what should you do?

Answer 40

take another set of blood cultures

Question 41

what is serum lactate a marker of?

Answer 41

generalised hypoperfusion/sever sepsis/poorer prognosis

Question 42

type A serum lactate shows?

Answer 42

hypoperfusion

Question 43

type B serum lactate shows?

Answer 43

mitochondrial toxins alcohol malignancy metabolism errors

Question 44

of the available biomarkers which one has the most support to identify adverse outcomes in sepsis?

Answer 44

lactate

Question 45

what is urine output a measure of?

Answer 45

renal dysfunction

Question 46

when would you consider a HDU referral in a septic patient?

Answer 46

* Low BP responsive to fluids * Lactate > 2 despite fluid resus * Elevated creatinine * Oliguria * Liver dysfunction, bil, PT, Plt * Bilateral infiltrates, hypoxaemia

Question 47

when would you consider a ITU referral in a septic patient?

Answer 47

When to Consider ITU Referral • Septic shock • Multi-organ failure • Requires sedation, intubation and ventilation