6. Sepsis and Infective Endocarditis

Question 1

Definition of bacteraemia

Answer 1

Transient presence of bacteria in the bloodstream

Question 2

Definition of septicaemia

Answer 2

Persistent presence of bacteria in the bloodstream with attendant signs and symptoms

Question 3

Definition of sepsis

Answer 3

Infection and SIRS

SIRS with a presumed/confirmed infectious process

Question 4

Definition of SIRS

Answer 4

Systemic inflammatory response syndrome

A clinical response arising from a non-specific insult

Question 5

Clinical features of SIRS (4)

Answer 5

Temperature <36C or >38C
HR/pulse >90bpm
Respiratory rate >20bpm or PaCO2 < 4.3pKa
WCC <4,000cells/mm3 or >12,000cells/mm3

Question 6

Types of sepsis (3)

Answer 6

Sepsis
Severe sepsis
Septic shock

Question 7

Definition of severe sepsis

Answer 7

Sepsis with one or more signs of organ dysfunction/failure (includes microvascular opening/rash)

Question 8

Types of organ failure (7)

Answer 8

Cardiovascular (refractory hypotension)
Renal
Respiratory
Hepatic
Haematological
CNS
Metabolic acidosis

Question 9

Definition of septic shock

Answer 9

Sepsis plus shock refractory to fluid resuscitation

Question 10

What is sepsis (2)

Answer 10

Uncontrolled, unregulated, self-sustaining intravascular inflammation
Involves a cytokine storm

Question 11

Definition of cytokine storm (2)

Answer 11

Unregulated simultaneous release of pro-inflammatory and anti-inflammatory elements out of balance
Extending to otherwise normal tissue

Question 12

Reactions to sepsis

Answer 12

Endothelial damage
Microvascular dysfunction
Impaired tissue oxygenation
Organ injury

Question 13

Gram negative septicaemia clinical features result from

Answer 13

Endotoxin release

Mainly hospital-acquired (E. coli)

Question 14

Gram positive septicaemia clinical features result from

Answer 14

Teichoic acid and peptidoglycan from cell wall

Question 15

Sources of infection (4)

Answer 15

Skin
Respiratory tract
Bone/joint infections
Oral cavity

Question 16

Who does fungal septicaemia affect

Answer 16

Immunosuppressed hosts (disease of the diseased)

Question 17

Septicaemia treatment (3)

Answer 17

Aggressive early treatment (IV antibiotics, oxygen, blind empirical antibiotics)
Modify treatment when culture available
Identify and remove source

Question 18

Septicaemia diagnosis (4)

Answer 18

Blood cultures
Cultures of other infected sites
Detection of microbial products in serum
Molecular methods (PCR)

Question 19

Sepsis 6 (6)

Answer 19

Give O2 to keep SATS >94%
Take blood cultures
Give IV antibiotics
Give fluid challenge
Measure lactate
Measure urine output

Question 20

Sepsis 6 - Why should you give O2 to keep SATS >94%

Answer 20

To maintain oxygen supply to organs, decreasing risk of failure

Question 21

Sepsis 6 - Why should you take blood cultures

Answer 21

To identify source of infection and pathogen causing it

Question 22

Sepsis 6 - Why should you give IV antibiotics

Answer 22

To get rid of the infection-causing pathogen

Question 23

Sepsis 6 - Why should you give fluid challenge

Answer 23

Maintain hydration - challenge patient to drink certain amount

Question 24

Sepsis 6 - Why should you measure lactate

Answer 24

Measurement of tissue dysfunction

Question 25

Sepsis 6 - Why should you measure urine output

Answer 25

Measurement of metabolism of tissue and organs (urea conc.)

Question 26

Definition of infective endocarditis

Answer 26

Microbial infection of the endothelial lining of the heart

Question 27

Manifestation of infective endocarditis

Answer 27

Vegetations on heart valves, involves microbial colonisation of thrombi on surface irregularities

Question 28

What does infective endocarditis cause

Answer 28

Haemodynamics and blood flow of heart to change, allowing bacteria to enter blood and accumulate in valves

Question 29

Treatment of infective endocarditis

Answer 29

Surgical valve removal and prosthetic heart valve insertion

Question 30

Problems with prosthetic heart valve

Answer 30

More suitable site for pathogens to adhere to

Question 31

Infective endocarditis portals of entry (3)

Answer 31

Oral cavity Skin breach Haematological spread

Question 32

Patients at higher risk of infective endocarditis (6)

Answer 32

``` Acquired valve disease Prosthetic valve Structural congenital heart disease Previous endocarditis Hypertrophic cardiomyopathy Recurrent bacteraemia ```

Question 33

Infective endocarditis diagnosis (4)

Answer 33

Clinical signs Blood cultures (x3 over 24hrs) Echocardiography DUKE criteria (positive micro blood cultures, evidence of endocardial involvement)

Question 34

Infective endocarditis antimicrobial treatment (4)

Answer 34

Broad-spectrum initially, guide by lab results Consider multiple drug combo Monitor drug levels Cardiac monitoring