Antimicrobial OBJECTIVES Flashcards
prophylactic coverage
attempt to prevent an infection before it is encountered
often done before surgery
empiric coverage
giving an antibiotic that will cover all of the most likely pathogens affiliated with a particular infection
not sure what it is so cover for all while getting a culture to narrow down
targeted coverage
give antibiotics for a specific pathogen
helps eliminate unnecessary and excessive coverage
broad spectrum
antibiotic that treats/covers a variety of organisms
typically both gram positives and gram negatives (and resistant organisms)
when would you use broad spectrum Abx?
used for empiric/initial treatment of suspected infection
narrow spectrum
antibiotic with limited pathogen coverage
may be due to nature of antibiotic or resistance issues
when would you use narrow spectrum Abx?
for treatment of specific pathogen (via culture or patient history)
bacteriostatic agents
antimicrobials that inhabit bacterial GROWTH
requires host immune system to eliminate bacteria that are there
bactericidal agents
antimicrobial that directly destroys the bacteria
used in patients who are immunocompromised (no immune system to fight what is left) or serious infections
bioavailability
% of a drug that gets into the body when given orally as compared to IV
drugs with high bioavailability have same IV doses and PO doses
what factors must be considered when prescribing antibiotics to the elderly?
different dosing due to
- muscle wasting
- renal dysfunction
- adverse events
reduced renal function and antibiotics
often found in elderly
may potentially underdose an antibiotic
elderly and adverse events
more susceptible
i.e. cephalosporins can cause hallucinations
must reduce the dose or we will overdose and do harm
steps in selecting an antibiotic regimen
- consider infection (site. common organism, PO/IV)
- consider patient (age, allergies, renal, CI)
- cost effective
- don’t be redundant – most coverage, no duplicate coverage, different targets)
- be convenient (appropriate dosing, PO are better)
goals of antimicrobial stewardship (4)
- reduce complications and risk of adverse events
- improve outcomes
- use more cost effective regimens
- reduce emergence of bacterial resistance
benefits of antimicrobial stewardship
- reduce C diff rates
- reduce resistance rates
- improve approbate use and clinical outcomes
- reduce cost of care (less spending on Abx, fewer readmissions, lower resistance rates, decrease complications)
why are beta lactams preferred over other antibiotics?
work quickly
potent
bactericidal
mechanism of action Beta lactams
cause bacterial cell wall
bactericidal, potent and rapidly kill bacteria
drug of choice when they are susceptible
drug of choice for syphilis
penicillin
drug of choice for MSSA bacteremia
IV Antistaaphyloccocal penicillin
nafcillin/oxacillin
drug of choice for enterococcal infections
aminopenicillins
beta lactamases
enzymes produced by bacteria that render beta lactam antibiotics ineffective
make bacteria more resistant to Abx
Beta lactamase inhibitors increased spectrum by:
adding coverage of
Gram -,
staph species,
strep pneumoniae
Beta lactamase inhibitors
drugs that inhibit beta lactamase in bacteria
