L15: Antimicrobial Resistance and Stewardship Flashcards
When were antibiotics first developed? How does this related to antibiotic resistance?
Antibiotics developed 2 billion to 40 million years ago
Resistance–> Similar age
How can they determine when antibiotic resistance developed?
Drill down into permafrost–> 30000 years ago
(before antibiotics perscribed)
Extract bacteria
Genetic analysis to show genes with resistance
What was the first evidence of resistance?
Resistance to penicillin in individuals that had never had penicillin
Naturally resistance strains that have survived because of survival of the fittest
How does horizontal gene transfer influence resistance?
Bacteria able to transfer resistance genes between each other
Overtime become more and more resistant
Antibiotics select for resistance
What effect does resistance have in a clinical setting?
Significant problem
Patient infected with bacteria with no antibiotics that aren’t resistant –> pan-resistance
Finding sensitive antibiotics can be difficult
What is one of the main problems with resistance?
It is irreversible
Bacteria cannot be cured of resistance
New antibacteria development not happening
What are the consequences of antibacterial resistance?
Treatment failure –> pan-drug resistance
Prophylaxis failure–> antibiotics prevent surgical site infections–> resistance means surgical site infections will rise and surgical operations will be reduced
Economic cost–> consequence, expensive to treat patients
Define multi-drug resistance (MDR)?
Non-susceptibilty to at least one agent in three or more antimicrobial categories
Define extensive drug resistance (XDR)?
Non-susceptibility to at least one agent in all but two or fewer antimicrobial categories
Define pan-drug resistance (PDR)?
Non-suscpetibility to all agents in all antimicrobial categories
Define not muti-drug resistance?
Isolates non-susceptible to >1 agent in <2 antimicrobial categories
What is antimicrobial stewardship?
An organisational or healthcare-system wide approach to promoting and monitoring judicious use of antimicrobial to preserve their future effectiveness
What does antimicrobial stewardship depend on?
Antibacterial use and resistance
Causal relationship
What is the evidence that antibacterials cause resistance?
Laboratory evidence–> provides biological plausibility
Ecological studies–> relates level of antibiotic use in a population with levels of resistance
- Look at use one year, measure resistance the following year
- Not perfect as the antibiotics used may not be used in the patient that goes on to develop resistance
Individual level data–> prior antibacterial use in patient with subsequent presence of bacterial resistance (detected by culture or molecular means)
What are the objectives of antimicrobial stewardship?
Ensure appropriate use of antimicrobials
Optimal clinical outcomes
Minimise toxicity and other adverse events
Reduce the cost of health care for infections
Limit the selection for antimicrobial resistant strains
How do you go about achieving antimicrobial stewardship?
Requires a structure
- Multidisciplinary team and relationships to other quality/ safety teams –> drive appropriate use
- Surveillance–> process measures (what antimicrobials are being used) and outcome measure (what resistance has occurred)
- Interventions–> persuasive, restrictive and structural
Who is involved in a multi-disciplinary team for trying to achieve anti-microbial stewardship?
Medical microbiologist/ infectious disease physician Antimicrobial pharamcist Infection control nurse Hospital epidemiologist Information system specialist
What is antimicrobial stewardship in relationship with?
Infection prevention
Environmental decontamination–> keeping the hospital clean
What are the different types of interventions?
Persuasive
Restrictive
Structural
What is meant by persuasive intervention?
Education–> of resistance, making sure they are only used when necessary
Consensus–> guideline of when antimicrobials should be used if needed
Opinion leaders–> influential people, lead by example
Reminders–> when drugs are started, when they should be stopped
Audit
Feedback
What is meant by restrictive intervention?
Restricted susceptibility reporting –> have to have permission from microbiology
Formulary restrictions –> only certain amount of antibiotics allowed, have to request for more
Prior authorisation
Automatic stop order –> automatically stop prescription after certain time period
What is meant by structural intervention?
Computerised records
Rapid lab tests
Expert systems–> drive prescribing decisions, put in patient details, tells you what to prescribe and for how long
Quality monitoring
What is meant by process measures?
Measure the amount of antibiotics being used
Use a measurement called ‘defined daily dose–> widely accepted dose that will be given to a patient in a day
–> allows you to compare usage over time between different organisations
–> Divided by number of bed days to compensate for difference in size of hospitals
Also measure antibacterial classes used and appropriateness (adherence to guidelines)
Compare within the institution at different time periods and against other institutions
How is outcome measure measured?
Patient outcomes: did patient survive or die?
Emergence of resistance
Clostridium difficile infections rate–> complications, measure of usage of antibiotics
What are the challenges for stewardship?
Well developed in this country but…
- Need to consider long term confirmed and appropriate resources–> support still needed, still unresourced stewardship team
- Hospital leadership support–> needs challenging, still lots of clinicians that over prescribe that aren’t challenged due to their position
- Integration into organisational patient safety and quality of care structure and processes
Which intervention appears to be most effective?
Restrictive tends to get results faster
Persuasive takes more time but get the same results in the long run
Are there any unintended consequences?
Decrease antibiotic prescribing potential for patients to not get treatment they need–> little evidence if anything treatment seems to be more appropriate (right antibiotic for shorter period of time)
