Healthcare Associated Infections Flashcards

(46 cards)

1
Q

What are healthcare associated infections (HAI)?

A

Infections which were not present, or were in the pre symptomatic phase at the time of admission to hospital, but which arise 48 hours or more after admission or within 48 hours of discharge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What percentage of patients in Scotland develop HAI?

A

4.9%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Possible outcomes of HAI

A

Extended length of stay, pain, discomfort, permanent disability, death
Financial implications
Loss of public confidence and decreased staff morale
Litigation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Common HAIs

A
UTI 
Surgical site infection 
Pneumonia 
Blood stream infection
Eye/ear/nose/throat/mouth infection 
GI infection 
Skin and soft tissue 
Systemic 
LRTI 
CVC/PVC related 
Neonatal 
CNS 
Bone/joint 
Reproductive tract 
CVS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many bacteria are there in the adult human body?

A

10^14
10 bacterial cells to every human cell
1kg bacteria in the human gut alone
500 different species of bacteria have been isolated from human stool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

First line of defence against infection

A
Intact skin 
Normal bacterial flora 
Body secretions 
Coughing 
Gastric acid 
Flushing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why do ventilation and catheterisation increase the risk of HAI?

A

They bypass the body’s natural protective mechanisms (coughing and urination)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Second line defence against infection

A

Immune system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why are patients in hospital more vulnerable to microbial colonisation and infection?

A

People and inanimate objects all harbour microbes that may pose a risk to others, other patients are more likely to carry more microbes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What percentage of the population are colonised with staph aureus?

A

Approximately 30%, most with methicillin sensitive staph aureus (MSSA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How can the same strain of staph aureus that colonises the population cause infection?

A

Break in skin
Vascular device
Catheter associated UTI
Ventilator associated pneumonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What causes most HAI?

A

Disturbance in the bacterial-host equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is colonisation?

A

When bacteria are in or on the body but do not cause illness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is infection?

A

Where bacteria are in or on the body and cause illness, resulting in signs and symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Microbial factors leading to increased risk of infection

A
Resistance 
Virulence 
Transmissibility 
Increased survival ability 
Ability to evade host defences
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Host factors leading to increased risk of infection

A
Devices e.g. PVC, CVC, urinary catheter, ventilation 
Antibiotics 
Break in skin surface
Foreign bodies 
Immunosuppression 
Gastric acid suppression 
Age extremes 
Proximity to others 
Increased opportunity for infection e.g. poor hand washing 
Overcrowding
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Modes of transmission of microbes

A

Direct contact
Respiratory/droplet
Faecal-oral
Penetrating injury

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Chain of infection

A

Source of microbe
Transmission vector
Host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Ways to break the chain of infection

A
Risk awareness 
Standard IPC precautions 
Hand hygiene 
Personal protective equipment 
Vaccination 
Post exposure prophylaxis 
Environment
20
Q

What is cleaning?

A

Physical removal of organic material and microbial load reduction

21
Q

When can cleaning be used?

A

For low risk e.g. intact skin contact - stethoscopes, cots, mattresses

22
Q

When is cleaning essential?

A

Prior to disinfection/sterilisation

23
Q

What is disinfection?

A

Large reduction in microbial numbers, spores may remain

24
Q

When can disinfection be used?

A

For medium risk e.g. mucous membrane contact - bedpans, endoscopes

25
Method of cleaning
Detergent and water | Drying
26
Method of disinfection
Heat - pasteurisation, boiling | Chemical e.g. alcohol, chlorhexidine, hypochlorites, hydrogen peroxide
27
What is sterilisation?
Removal/destruction of all microbes and spores
28
When can sterilisation be used?
High risk e.g. penetration through the skin/sterile body cavities - surgical instruments
29
Methods of sterilisation
Steam under pressure - autoclave Hot air oven Gas Ionising radiation
30
Infection prevention and control surveillance methods
Local surveillance | National surveillance
31
Features of local surveillance - lab based
Lab detects microbe and notifies IPCT and clinicians Identify microbe and recommendations can be specific Depends on samples being sent, takes time to grow and identify microbe
32
Features of ward/clinical area based surveillance
Ward/clinical staff notify IPCT or microbiology Detects potential problem sooner and can ensure correct samples are sent Potential causative microbe is not always clear initially, IPC measures more general
33
Mandatory surveillance reporting for Scotland
``` MRSA bacteraemia MSSA bacteraemia C. diff E. coli bacteraemia Surgical sites ```
34
What is an outbreak?
2 or more defined cases of an infection linked in time and place
35
What is the purpose of the IPCT?
To prevent individual infections and outbreaks
36
What is the purpose of surveillance?
To detect and identify a possible outbreak at the earliest opportunity
37
Typing methods, to determine strain responsible
``` Antibiogram Phage typing Pyocin typing Serotyping Molecular typing ```
38
Control measures for outbreaks
``` Reinforcements of IPC measures Single room in isolation Cohorting of cases Ward/clinical area closure Staff/patient decolonisation Staff exclusion ```
39
Features of C. diff infection
Diarrhoea Abdominal pain, pyrexia, raised WCC Pseudomembranous colitis
40
In what percentage of adults is C. diff part of the normal gut flora?
Around 2%
41
Pattern of carriage rate of C. diff with age
C. diff carriage rate increases with age
42
What percentage of the elderly are colonised with C. diff?
Around 30%
43
When does C. diff infection occur?
When there is an imbalance in the gut flora due to an endogenous or exogenous source Variable in severity Elderly more at risk
44
What must be present for a diagnosis of C. diff infection to be made?
Diarrhoeal symptoms - positive toxin test does not always indicate disease
45
Possible reasons for increasing incidence
``` More antibiotics More of a particular type of antibiotic New strains Less hand washing due to more hand-gelling Increasing environmental contamination Increased number of vulnerable patients close together Increased throughput of patients Other drugs having effect ```
46
Treatment of C. diff
Stop predisposing antibiotic is possible Oral metronidazole if symptomatic Oral vancomycin if severe or failure of metronidazole Oral fidaxomicin