8.3 Infection Control

Question 1

Risk factors for the development of infectious complications after a central neuraxial block

Patient factors

Answer 1

Underlying sepsis
Diabetes
Localised bacterial infection
Chronic steroid therapy
Immunosupression

Question 2

Risk factors for the development of infectious complications after a central neuraxial block

Anaesthetic technique factors

Answer 2

Aseptic technique
Chronic catheter placement

there are no convincing data that an infection at remote sites or lack of
antibiotic prophylaxis is a risk factor for infection.

Question 3

PDPM - how common

Caused by

Answer 3

Meningitis following a spinal anaesthetic (post-dural puncture
meningitis – PDPM) is a rare event.

It is most commonly caused by

1
Streptococcus viridans
(mouth commensals),

2
Staphylococcus aureus,

3
Pseudomonas aeruginosa

4
Enterococcus faecalis

Question 4

Pathogenesis: PDPM

Normal path

difference

operator role?

Answer 4

Pathogenesis:

a successful meningeal pathogen must be able to colonise the host mucosal epithelium, then invade the intravascular space, cross the
blood–brain barrier and survive in the cerebrospinal fluid.

In PDPM, it is inoculated directly in the CSF somehow and circumvents the first three
obstacles.

Operator role has been suggested by 
isolation of same bacterial
types from patients having PDPM 
and nasal/oral cavities of the
neurologists/anesthesiologists 
who performed the procedure

Question 5

Epidural abscess following epidural anaesthetic

RF

Answer 5

Epidural abscess following epidural anaesthetic

can be a devastating
complication if not recognised
and treated in time.

Risk factors for the
development of an epidural abscess
include an

1
immunocompromised state

2
malignancy,

3
localised infections near epidural site,

4
thromboprophylaxis, and

5
chronic catheters.

Question 6

Epidural Abscess bugs

Commonest

CSE

meningitis

Answer 6

S. aureus is the most common

pathogen isolated followed
by streptococci and Gram-negative bacilli.

In the case of combined spinal epidural,
meningitis is most commonly
caused by S. viridans,

while an
epidural abscess is most
commonly caused by S. aureus

Question 7

Grades of recommendations for infection control while performing a peripheral nerve block

Answer 7

Grade A evidence:

Hand-washing
Cleaning skin with alcohol-based antiseptic
chlorhexidine
Wearing sterile gloves

Question 8

Grades of recommendations for infection control while performing a peripheral nerve block

Answer 8

Grade B evidence:

A new face mask for each new case
Remove jewellery before hand-washing
Allow the antiseptic to dry before starting (1 minute)
Use of bacterial filter for catheter techniques

Question 9

Grades of recommendations for infection control while performing a peripheral nerve block

Answer 9

Grade C evidence:
Antibiotic prophylaxis for catheter
placement

Question 10

Grades of recommendations for infection control while performing a peripheral nerve block

Answer 10

Grade D evidence:
At least two disinfections of procedure site
Wear sterile gowns for catheters
Use sterile mixtures and minimise disconnections for
top-up administration