Healthcare associated infections Flashcards
Define HAI
Infections not present or in the pre symptomatic phase at the time of admission to hospital
which arise >48 hours after admission or within 48 hours of discharge
4 possible outcomes of HAI
litigation
increased hospital stay, pain, discomfort, permanent disability and death
increased cost
loss of public confidence and decreased staff morale
6 most common sites of HAI
UTI respiratory tract infections skin and soft tissue infections GI infections bloodstream infections surgical site infection
How many different species of bacteria have been isolated from the human stool?
over 500
What percentage of the population is colonised with staph aureus and where is it found in humans?
30%
in their nose
Most people colonised with staph aureus is MRSA or MSSA?
MSSA
List 4 ways the same strain colonising can cause infection - examples
break in the skin eg surgical site infection
vascular device eg CVC
catheter associated UTI
ventilator associated pneumonia
5 microbial factors tipping the balance towards infection- increased…
virulence transmissibility ability to evade hosts immune defences resistance survival ability
List some host factors tipping the balance towards infection
break in the skin immunosuppression other drugs eg PPI devices eg catheter overcrowding age
3 parts of the chain of infection
source of microbe (endogenous or exogenous)
transmission
host
4 means of transmission and an example of a microbe transmitted this way
faecal oral - c diff
direct contact - staph aureus
respiratory/droplet - Neisseria meningitidis, TB
penetrating injury - blood borne viruses
List some ways to break the chain of infection
appropriate PPE SIPCs risk awareness closure of wards vaccination hand hygiene
Define cleaning
physical removal of organic material and decrease in microbial load
Define disinfection
Large reduction in microbe numbers - spores may remain
Define sterilisation
Removal or destruction of ALL microbes and spores
Give an example of a low risk piece of equipment and how to decontaminate it
stethoscope - intact skin contact
cleaning compatible with manufacturers instructions
Give an example of a medium risk piece of equipment and how to decontaminate it
mucous membrane - endoscope
disinfect or sterilise as appropriate
Give an example of a high risk piece of equipment and how to decontaminate it
surgical instruments
sterilisation
Explain the concept of cleaning
manufacturers instructions
detergent and water
drying
essential prior to disinfection and sterilisation
2 methods of disinfection
heat
chemicals
Heat - disinfection
pasteurisation or boiling
Heat - chemical
vary in organism range and must be equipment compatible
eg alcohol, Hydrogen peroxide
4 ways to sterilise
steam under pressure - autoclave
hot air oven
gas
ionising radiation
Define outbreak
2or more cases of an infection linked in time and place
What is the first purpose of IPC?
prevent individual infections and outbreaks
What is the purpose of surveillance?
detect and identify a possible outbreak at the earliest opportunity
What must be done to confirm an outbreak?
typing
5 typing methods
antiobiogram - antibiotic sensitivity pattern phage typing serotyping pyocin typing molecular typing
6 outbreak control measures
single room isolation ward closure staff exclusion cohort cases reinforce PIC measures staff decolonisation
Clinical characteristics of C diff
diarrhoea
faeces have characteristic odour
abdominal pain, pyrexia, increased WCC
pseudomembranous colitis
Epidemiology of c. diff colonisation
2% population
increases with age
30% elderly
Do toxin negative strains of c.diff cause disease?
no
What makes you more susceptible to c.diff infection?
imbalance in gut flora
elderly
antibiotics
What needs to be present for a c.diff diagnosis?
diarrhoea
First thing to do in c.diff infection
stop antibiotics predisposing if possible
Symptomatic treatment of c.diff
oral metronidazole
oral Vancomycin if severe
oral fidaxomicin if 2nd episode
4 C antibiotics
cephalosporins
co-amoxiclav
clindamycin
ciprofloxacin
