Healthcare associated infections

Question 1

what is a healthcare associated infection

Answer 1

Healthcare Associated Infection -HAI- (Nosocomial infection) is one that is not present or incubating when a patient is admitted to hospital.

Question 2

who is it a major problem for (2 people)

Answer 2

patients- but also staff

Question 3

what is the US data

Answer 3

4% of all admissions and rates increasing
Prolonged stays by 4-13 days.
20-35 Billion Dollars
687,000 cases and 72,000 deaths 2015

Question 4

what is the cost to the NHS in England and Wales

Answer 4

£2 bn+ in costs annually
20K annual deaths of patients with HAI

Question 5

What are the European HAI levels

Answer 5

4,000,000 get a HAI annually
37,000 fatalities

Question 6

what are the % of admissions in developed countries

Answer 6

5-10

Question 7

what are the % of admissions in developing countries

Answer 7

10-30

Question 8

how likely are the patients to die

Answer 8

Patients with nosocomial infection are 7.1 times more likely to die

Question 9

how long do they stay in hospital

Answer 9

Patients with an infection remain in hospital on average 2.5 times longer than other patients
-average additional length of stay is 11 days
-Increased cost and Increased risk

Question 10

where do the disease rates vary

Answer 10

-vary between countries, within a country, between hospitals and even within a hospital
-Different mixtures of patients (geriatric v maternity)
-Differing treatments (cancer v orthopaedic)
-Differing policies

Question 11

what are the 2 classes for HAI

Answer 11

Endogenous and exogenous

Question 12

explain endogenous

Answer 12

-Organism is part of the normal microbiota of the patient.
-Acts as an opportunistic pathogen
-Underlying health issues for patient= Innate immunity compromised
-Medical interventions on patient= Innate immunity compromised

Question 13

Explain a exogenous infection

Answer 13

Organism comes from other patients, hospital personnel, equipment or environment= Can be an opportunistic pathogen or a true pathogen

Question 14

how do exogenous pathogens spread

Answer 14

-direct contact= Staff-patient, patient-patient and visitors may also have a role but more difficult to prove.
-fomites= Medical and other devices passed between patients
-air
-water

Question 15

What are the risk factors for HAI in Nursing homes

Answer 15

-Compromised patients
-Infected patients as reservoirs of infection
-Crowding predisposes to infection
-Interaction of individual staff with many patients

Question 16

what are the risk factors of HAI in newbornes

Answer 16

Newborns at risk due to immature immune systems

Question 17

what are the general risk factors for HAI (procedures and control)

Answer 17

-Many procedures can overcome the innate host defence mechanisms= Surgery, Immunosuppression, Injection, Catheterisation and Biopsy
-Control of infection by antibiotics can predispose to superinfection by yeasts and other exotic microorganisms.

Question 18

what are CAUTIs

Answer 18

Catheter-associated urinary tract infections- A urinary tract infection (UTI) is an infection involving any part of the urinary system, including urethra, bladder, ureters, and kidney

Question 19

what are the main groups for HAIs

Answer 19

-Urinary tract infections= Catheter-associated Urinary Tract Infections
-Surgical wound infections=12%
-Lower respiratory infections= Ventilator-associated Pneumonia and VAP
-Septicaemia= Central line associated Bloodstream Infections (CLABSIs)

Question 20

what is Ventilation associated pneumonia

Answer 20

pneumonia occurring more than 48 h after patients have been intubated and received mechanical ventilation

Question 21

what are central lines

Answer 21

intravascular catheter that terminates at or close to the heart or in one of the GREAT VESSELS which is used for infusion, blood withdrawal or hemodynamic monitoring

Question 22

what are some of the great vessels

Answer 22

Aorta
Pulmonary arteries
Superior vena cava
Inferior vena cava
Brachiocephalic veins
Internal jugular veins
Subclavian veins
External iliac veins
Common iliac veins
Femoral veins
Umbilical artery and veins in neonates

Question 23

what are the ESKAPE pathogens

Answer 23

Enterococcus faecium
Staphylococcus aureus
Klebsiella pneumoniae
Acinetobacter baumannii
Pseudomonas aeruginosa
Enterobacter spp.

Question 24

what is MRSA

Answer 24

-Methicillin Resistant Staphylococcus aureus
-Found on nose and on the skin of many healthy people without causing harm.
-Causes boils, abscesses , wound infections, sepsis and pneumonia
particularly in those who are already unwell.
-difficult to treat by commonly prescribed antibiotics.
-Some strains of Staphylococcus aureus are resistant to an antibiotic called Methicillin (and up to 18 other antibiotics!!)
Rates have declined over the last decade or so but still a major pathogen.

Question 25

What are the cost effects of MRSA

Answer 25

Costly interventions that have taken a decade to see results

Question 26

what is the timeline of MRSA

Answer 26

1959, methicillin introduced in the UK
1961, methicillin resistance first reported
1960’s, methicillin used in labs to detect resistance
1970’s, MRSA outbreaks in UK & Europe
1979, major outbreak in Melbourne Hospital Australia
1981, first epidemic MRSA strain (EMRSA1)
2000+ strains resistant to up to 16 antibiotics

Question 27

when did penicillin resistance emerge

Answer 27

1940s

Question 28

in the 1950s what was the % of penicillin resistance

Answer 28

95%

Question 29

what is C.diff or C.difficile

Answer 29

Clostridioides difficile
It is a Sporeformer Anaerobe, Rod shaped, GI tract inhabitant and CDI is a major cause of death in hospitalised patients - it was a lcoal problem in N.I as well as an international problem

Question 30

what does C.difficile cause in patients

Answer 30

-induced diarrhea in hospitalized adults
-The disease can be mild or severe= Pseudomembranous colitis, Bowel perforation, Toxic megacolon, Sepsis
-Only occurs after intense antibiotic therapy= disruption of gut normal flora allows C. difficile to grow-Dysbiosis
-Virulence mainly due to two toxins: A and B
-Treatment is supportive and involves discontinuing antibiotic therapy
-Diagnosis is made based on detection of toxins in the stool

Question 31

what are the treatment options for C.difficile

Answer 31

stopping the antibiotics thought to be causing the infection, if possible
try different antibiotics
taking a 10 to 14-day course of antibiotics that are known to kill C.difficile

Question 32

what are the mechanisms of control of HAIs

Answer 32

-Aseptic techniques= hand washing and the use of gloves
-Isolation policies
-Food handling procedures
-Disinfection protocols= concurrent and terminal
-Waste disposal regimes
-Surgical wound dressing= SOPs
-Catheter insertion= SOPs
-Cannula insertion= SOPs
(infections rates are decreasing)

Question 33

how do we prevent the spread of HAIs ( reduce what)

Answer 33

Reduce Contacts= patient-to-patient and staff-to-patient

Question 34

what are the 2 main isolation strategies

Answer 34

Forward isolation and reverse isolation

Question 35

what is forward isolation

Answer 35

-Different classes of isolation= Strict, Contact, Private room (self contained) and Respiratory etc.
-Designed to prevent microbes getting from infected patent to others in hospital environment= make COVID wards and Influenza wards in 1918-19
-Strict disinfection programmes
-Negative pressure may be used
Air enters room via unsealed doors etc. and is sterilized by HEPA filters,
prevents airborne organisms within the room entering other parts of the hospital as they cannot move against the air flow

Question 36

what is reverse isolation

Answer 36

-Private room (self contained)
-Designed to prevent microbes from the hospital environment getting to a severely compromised patient= Immunosuppressed, cancer chemotherapy, Stem cell transplantation etc.
-Positive pressure=Sterile air fed into room (sterilized by HEPA filters) and exits through doors, prevents airborne organisms from entering the room as they cannot move against the air flow

Question 37

How do we control HAI (pcs)

Answer 37

Prevention= Barrier nursing etc.
Surveillance= Regular checks for the presence of target microbes
Control= Break transmission cycles and Kill/remove pathogens

Question 38

what are infection control committees

Answer 38

Representative of microbiology laboratory, Infection Control Nurse and Nursing representative

Question 39

what is the history of infection control

Answer 39

-Ignác Semmelweis (1818-1865)= Observed that up to 1/5 women died from “childbed” puerperal fever after physician-assisted delivery due to Staphylococcus aureus, by contrast, mortality was low in deliveries performed by midwives
-There was no PPE in the mid-19th century! Little disinfection either.
Pathogens, particularly Staphylococcus aureus, easily transferred by direct contact
-Semmelweis discovered that doctors handwashing with carbolic acid prior to delivery dramatically reduced mortality in women
he wrote letters to the establishment outlining his discovery and had opposition
-Suffered a nervous breakdown and was declared a lunatic and institutionalized, died from blood poisoning 10 d after receiving a finger cut while forced into a straightjacket