Pathogenesis of Sepsis and antibiotics

Question 1

What is septic shock?

Answer 1

Sepsis with acute or refractory hypotension or tissue hypoperfusion despite fluid resuscitation

Question 2

SIRS temperature?

Answer 2

> 38 or <36

Question 3

SIRS RR?

or SIRS PaCO2?

Answer 3

> or equal to 20/min

or < 32 mmHg (normal: 38-42)

Question 4

SIRS WBC?

Answer 4

12,000/ul or over
or 4,000/ul or under
or >10% immature forms

Question 5

What is sepsis?

Answer 5

At least two SIRS criteria caused by an infection (known or suspected)

Question 6

What is LPS?

Answer 6

An endotoxin secreted by gram negative bacteria

Question 7

What is the most common cause of shock from gram negatives?

Answer 7

LPS

Question 8

What is the most common cause of shock from gram positives?

Answer 8

Lipoteichoic acid

Question 9

Direct cause of shock by microbe?

Answer 9

Interaction with the vascular endothelium

Question 10

Common producers of super antigens?

Answer 10

S. aureus
Streptococcus pyrogenese (group A strep)

Question 11

What does a superantigen do?

Answer 11

Directly attach to MHC class II and TCR causing faster and prolonged response

Question 12

What effect of sepsis causes tissue hypo-perfusion

Answer 12

Increased coagulation, loss of red cell deformability, decrease in BP (leaky vessels)

Question 13

G -ve causes of shock?

Answer 13

E. coli
Meningococci
Pseudomonas
Haemophilus

Question 14

G +ve causes of shock?

Answer 14

Staph aureus
Group A streptococci
Strep pneumoniae
Clostridium spp.

Question 15

Causes of neonatal shock?

Answer 15

Group B streptococci
Listeria
E. coli

Question 16

What does strep pneumoniae cause?

Answer 16

Pneumonia and meningitis

Question 17

What fungus is common in the immunosuppressed?

Answer 17

Aspergilus

Question 18

Common bacteraemias:

Answer 18

S. aureus (+)
Enterococcus (+)
Strep pneumoniae (+)

E. coli (-)
Klebsiella (-)
Pseudomonas (-)

Question 19

Most common cause of g -ve septicaemia in hospital?

Answer 19

UTI with pyelonephritis

Question 20

Hospital cause of septicaemia?

Answer 20

IV catheters and devices

Question 21

Differentials for septic shock

Answer 21

Burns or trauma
Pancreatitis
PE (resembles pneumonia)
Ruptured AAA, bleed, MI, tamponade
Overdose
Adrenal insufficiency
Anaphylaxis

Question 22

Management of sepsis?

Answer 22

Fluids
Dopamine
Transfusion (ICU)
Solve precipitating problem
Anti-biotics

Question 23

Monitor what in sepsis?

Answer 23

ABG
Renal function (U+E's)
CNS
Glasgow coma score (GCS)
LFTs
Myocardial function

Question 24

Sepsis 6:

Answer 24

1: Administer high flow O2
2: Blood cultures
3: Broad spectrum anti-biotics
4: IV fluid challenges
5: Measure serum lactate and Hb
6: Measure hourly urine output

Question 25

When do should IV abx have begun?

Answer 25

Within the first hour of admission

Question 26

Consider what in neutropenic patients?

Answer 26

Combination empiric therapy

Question 27

What is de-escalation?

Answer 27

Going from broad spectrum antibiotics to narrow | Carry out once cultures come back

Question 28

Examples of beta-lactams:

Answer 28

Penicillins, cephalosporins and carbapenems (ertapenem, meropenem)

Question 29

Glycopeptide Abx:

Answer 29

Vancomycin | Teicoplanin

Question 30

What are glycopeptide Abx used for?

Answer 30

G +ve MRSA Coagulase -ve staphylococcus

Question 31

Bactericidal vs bacteriostatic:

Answer 31

Kill vs stop growth

Question 32

-mycin =

Answer 32

Macrolide (bacteriostatic)

Question 33

When might a macrolide be used?

Answer 33

Penicillin allergy against staph and strep e.g. skin/throat | Atypical pneumonia

Question 34

-cycline

Answer 34

Tetracycline (bacteriostatic, broad spec)

Question 35

When might a tetracycline be used?

Answer 35

Respiratory and soft tissue atypicals e.g. legionella and mycoplasma

Question 36

Tigecycline is effective against?

Answer 36

G +ve G -ve Anaerobes

Question 37

Aminoglycosides are used for what?

Answer 37

G -ve Synergy with penicillins against strep and others Used for serious sepsis

Question 38

Potential complication of macrolide use? (except tobramycin)

Answer 38

Nephrotoxicity | CN VII toxicity

Question 39

Penicillins ordered from broad (top) to specific (bottom):

Answer 39

``` Tazobactam Co-amoxicillin Amoxicillin Penicillin V PO ```

Question 40

Function of quinolones?

Answer 40

Prevents DNA synthesis

Question 41

-oxacin

Answer 41

Quinolone

Question 42

Examples of quinolones:

Answer 42

Ciprofloxacin Levofloxacin Maxifloxacin

Question 43

Use for trimethoprim?

Answer 43

UTI

Question 44

Potential complications of trimethoprim and co-trimoxazole?

Answer 44

``` Interfere with folate G +ve side effects G -ve side effects Stevens-Johnson syndrome Bone marrow suppression/aplasia ```

Question 45

In which situations do abx not help the patient get better quicker?

Answer 45

Comylobacter | Acute bacterial sinusitis

Question 46

Treatment for: CAI and shock Origin unknown/gut/renal/biliary

Answer 46

Co-amoxiclav + gentamicin (+vancomycin if MRSA) or cefuroxime + metronidazole + gentamicin or ciprofloxacin + metronidazole + gentamicin

Question 47

Treatment for: CAI and shock Origin skin/soft tissue

Answer 47

Flucoxacillin + penicillin/amoxicillin +/- gentamicin | consider adding clyndamicin if group A strep or staph. aureus - risk of toxic shock

Question 48

Treatment for: CAI and shock Pneumonia

Answer 48

co-amoxiclav + doxycycline | or cefuroxime + erythromycin

Question 49

Treatment for: CAI and shock Meningococcal disease

Answer 49

Penicillin or ceftriaxone

Question 50

Treatment for: CAI and shock Malaria

Answer 50

Quinine

Question 51

Penicillin allergy (rash only)

Answer 51

Consider using penicillin or cephalosporin depending on the allergy

Question 52

Penicillin allergy (severe i.e. anaphylaxis)

Answer 52

Ciprofloxacin, vancomycin, eryhthromycin (get advice) | No beta-lactams at all

Question 53

HAI vs CAI

Answer 53

For HAI you have to go more broad spectrum

Question 54

Early HAI abx

Answer 54

Same as CAI

Question 55

Late HAI abx

Answer 55

Broad Gentamicin + Tazocin (maybe meropenem or colistin as resistance that bad)

Question 56

MRSA abx:

Answer 56

Vancomycin

Question 57

VRE

Answer 57

Linezolid