sepsis and septic shock

Question 1

Systemic inflammatory response syndrome

Answer 1

• Temp: >38oC or <36oC
• HR >90
• RR >20 or PaCO2 <32
• WBCs > 12000 or < 4000 or >10% bands (immature forms)
• SIRS does not always indicate infection. Can occur following burns, pancreatitis, surgery.

Question 2

sepsis

Answer 2

life threatening organ dysfunction
dysregulated host response to infection
acute change in SOFA score >2 points consequent to infection

Question 3

septic shock

Answer 3

sepsis with persisting hypotension requiring vasopressors to maintain MAP >65mmHg and serum lactate of >2mmol/l
high mortality

Question 4

serum lactate

Answer 4

amount of lactic acid in the blood and is a fairly sensitive and reliable indicator of tissue hypoperfusion and hypoxia. Any disorder that causes an imbalance between lactate production and clearance can lead to lactic acidosis, a serious and sometimes life-threatening condition

Question 5

qSOFA score (2 or more risk of poor outcome)

Answer 5

Hypotension
altered mental status
tachypnoea
systolic BP <100mmHg
confusion ( not neccessarily GCS)
RR>22`

Question 6

pathophysiology

Answer 6

Breach of body's natural defence
uncontrolled inflam response
immunosuppresion features
presdiposition to nosocomial
loss of delayed hypersensitivity
probably change of sepsis syndrome over time
-initially increase in inflam mediators
-later shift toward anti inflam immunosuppresive

Question 7

pathogenesis

Answer 7

release of bacterial toxins
commonly released toxins
Gram-ve: lipopolysaccharide
Gram +ve: Microbial associated molecular pattern
a. lipoteichoic acid
b. muramyl dipeptides
Superantigens
a.staphylococcal toxic shock syndrome toxin
streptoccocal exotoxins

Question 8

release of mediators

Answer 8

endotoxin release
LPS need LPS binding protein
LTA doesnt
exotoxin
-proinflam response
-small amount of superantigens large mediators secreted

Question 9

Mediators

Answer 9

TH1: Pro inflam mediators cause inflammatory response that characterise sepsis
TH2: compensatory anti inflam- can cause immunoparalysis

Question 10

pro inflam mediators

Answer 10

promote endothelial cell- leukocyte adhesion
release of arachidonic acid metabolites
complement activation
vasodilation of blood vessels-erythema
increase coagulation by release of tissue factor
hyperthermia-> TNF alpha release

Question 11

Anti-inflam mediators

Answer 11

inhibit TNF alpha
augment acute phase reaction
inhibit activation of coagulation system
negative feedback mechanism to pto inflam

Question 12

balance

Answer 12

Excess anti-inflammatory: septic shock with multi-organ failure and death
Excess pro-inflammatory: immunoparalysis with uncontrolled infection and multi-organ failure

Question 13

Immunoparalysis

Answer 13

Persistence of a marked compensatory anti-inflammatory innate immune response following an insult such as sepsis or trauma

Question 14

general feature of sepsis

Answer 14

fever
hypothermia
tachycardia
tachypnoea >20/min
hyperhlycemia >8mmol/l absence of diabetes

Question 15

inflammatory

Answer 15

leucocytosis (>12000)
leucopenia (<4000)
greater than 10% immature
high CRP
high procalcitonin (elevated only in patients with active infection)

Question 16

haemodynamic-

Answer 16

arterial hypotension

SvO2 > 70%

Question 17

Organ dysfunction

Answer 17

arterial hypoxaemia
oliguria
creatinine increased
coagulation abnormalities
Ileus
thrombocytopenia
hyperbilirubinaemia

Question 18

tissue perfusion

Answer 18

high lactate!
indicates hypoperfusion

skin mottling and reduced capillary perfusion

Question 19

effects of host

Answer 19

age
comorbidities
immunosuppresion
congenital-agammaglobulinaemia
surgery- splenectomy

Question 20

effects of organism

Answer 20

gram+ve above diaphragm
gram-ve under diaphragm
virulence factors (MRSA toxin secretion)
bioburden

Question 21

sepsis 6

Answer 21

give 3
oxygen aim 94 -98
iv antibio
iv fluid challenge
take 3
blood cultures
blood lactate
measure urine output

Question 22

blood cultures

Answer 22

microbiological diagnosis

Question 23

type A

Answer 23

hypoperfusion

Question 24

type B

Answer 24

mitocohondrial toxins, alcohol, malignancy, metabolism errors

Question 25

antibiotics

Answer 25

o Local antibiotic guidelines
♣ Consider allergy
♣ Consider previous MRSA, ESBL, CPE
Consider toxicity & interactions

Question 26

IV fluids

Answer 26

30ml/kg fluid challenge
Fluid challenges require the definition of four components:
1) the type of fluid to be administered
2) the rate of fluid infusion (e.g., 500 mL to 1,000 mL over 30 minutes)
3) the end points (e.g., mean arterial pressure of >65 mm Hg, heart rate of <110 beats per minute)
4) the safety limits (e.g., development of pulmonary oedema)

Question 27

When to refer to HDU

Answer 27

• Low BP responsive to fluids
• Lactate >2 despite fluid resuscitation
• Elevated creatinine (>2)
• Oliguria (< 0.5 mL/kg/hr for more than 2 hrs despite adequate fluid resuscitation)
• Liver dysfunction
o Bilirubin > 2 mg/dL (34.2 μmol/L)
o Platelet count < 100,000 μL
o Coagulopathy (INR > 1.5)
• Bilateral infiltrates, hypoxaemia
• Acute lung injury with Pao2/Fio2 < 250 in the absence of pneumonia as infection source
• Acute lung injury with Pao2/Fio2 < 200 in the presence of pneumonia as infection source

Question 28

when to refer ITU

Answer 28

septic shock
multiorgan failute
requires
sedation, intubation and ventilation