Antimicrobial Stewardship Flashcards
(180 cards)
1
Q
define mechanism of action
A
how a drug inhibits or kills bacteria
2
Q
define spectrum of activity
A
which bacteria the drug is able to cover
3
Q
does cidal or static require more drug?
A
static
4
Q
define cidal
A
kills bacteria on its own and requires less drug to do so
5
Q
define static
A
inhibits future growth of bacteria and require more drug and immune system assistance
6
Q
what are 3 parameters we can use to optimize the way antibiotics kill bacteria?
A
- Time > MIC
- Cmax > MIC (max concentration above the MIC)
- AUC/MIC
7
Q
drug concentration needs to be above the ___ for as long as possible
A
MIC
8
Q
which drugs need to be above the MIC?
A
time-dependent killers
9
Q
are beta lactams cidal or static?
A
cidal
10
Q
true or false. You want to optimize time above the MIC with beta-lactams
A
True
11
Q
list some beta-lactam drugs
A
penicillins, cephlasporins, carbapenemes, aztreonam (monobactam)
12
Q
what routes can penicillin be given?
A
IV, IM, or oral
13
Q
what is the drug of choice for susceptible enterococcus and listeria?
A
aminopenicillin
14
Q
what are some examples of antistaphylcoccal penicillins?
A
-Nafcillin
-oxacillin
-dicloxacillin
15
Q
which drug has no activity against enterococcus?
A
cephlasporins
16
Q
Augmentin is a combination of what drugs? (PO)
A
amoxycillin and clavulate
17
Q
Unasyn is a combination of which drugs? (IV)
A
ampicillin and sulbactam
18
Q
what is unasyn used for?
A
bite wounds
19
Q
Zosyn is a combination of which drugs?
A
piperacillin and tazobactam
20
Q
which drug is known as vitamin z?
A
zosyn
21
Q
what broad spectrum treatment is given if infection is suspected in the ER (hint: it covers MRSA and pseudomonas. You must monitor kidney function)
A
vancomycin and zosyn
22
Q
Which drug class has no activity against enterococcus?
A
cephlasporins
23
Q
Which cephlasporin is primarily used against gram negative bacteria but can treat some gram positive infections like strep?
A
Cefepime
24
Q
as you move from 1st generation cephlasporins down, you lose gram ___ and gain gram ____ activity. The exception is the ___ generation
A
positive; negative; 5th (covers MRSA but not pseudomonas)
25
which drug combination is used for the most drug-resistant bacteria?
cephlasporins and beta-lactamase inhibitors
26
do cephlasporins + beta-lactamase inhibitors have acctivity against enterococcus?
No
27
List 2 cephlsporin + beta lactamase inhibitor drug combos
-ceftolozane/tazobactam (zerbaxa)
-ceftazidime/avibactam (Avycaz)
28
which carbapenems are seen most often?
entrapenem and meropenem
29
is entrapenem broad or narrow?
narrow
30
which carbapenem has a high rate of causing seizures?
Imipenem. It is reserved for infections with unique activity/nocardia
31
all carbapenems have the possibility to cause seizures by
lowering the threshold to have a seizure
32
Which carbapenem can treat APE (acinetobacter, pseudomonas, and enterococcus) and which carbapenem can't?
Mertapenem can; ertapenem can't
33
Which drugs are carbapenems?
-ertapenem (Invanz)
-Doripenem (doribax)
-Meroapenem (Merrem)
-Imipenem/Cilastatin (primaxin)
34
Do not use ___ ___ with carbapenems
valproic acid
35
aztreonam has gram ___ activity only
negative
36
Which drug has an inhaled form which is typically used for the cystic fibrosis population which are normally colonized with pseudomonas?
Aztreonam
37
Aztreonam combined with ____ could treat carbapenemase resistant infections
Avibactam
38
True or false. Aztreonam is used a lot.
False. It is not used a lot because of resistance.
39
Are fluroquinolones time or concentration dependent?
concentration
40
what is the mechanism of action for fluroquinolones?
inhibit DNA gyrase, resulting in DNA breakage
41
What year was the first fluroquinolone introduced?
1964
42
what are some potential side effects of fluoroquinolines?
-ruptures or tears of the aortta
-hypoglycemic risks
-psyhciatric risks
-joint pain, tendon rupture, anxiety, depression, altered mental status, peripheral neuropathy
43
What is the PK/PD of beta lactams?
T>MIC (optimize time above the MIC)
44
what is the PK/PD of fluroquinolones?
AUC: MIC
45
What is the PK/PD of aminoglycosides?
Cmax/MIC
46
What is the mechanism of action of aminoglycosides?
inhibits protein synthesis at the level of the ribosome
47
what are some ADEs of aminoglycosides?
nephrotoxicity, ototoxicity (kidneys and hearing affected... think of the meme)
48
True or false. Pharmacy doses aminoglycosides in a patient specific manner and they are almost always used in combination with something else
True
49
Aminoglycosides are almost always used for gram ____ infections
negative
50
what are aminoglycosides usually used to treat?
resistance or infection of the heart
51
what is the mechanism of action for macrolides?
they are static and inhibit protein synthesis at the ribosome
52
What are some ADEs of macrolides?
QTc prolongation, GI upset
53
with which drug do we see resistance because it is used to treat viral infections like colds?
azithromycin
54
what is the mechanism of action for sulfonamides?
interferes with bacterial folic acid synthesis (static)
55
Bactrim (the oral option for MRSA) is a combination of which drugs?
sulfamethoxozole and trimethoprim
56
what are some ADEs of sulfonamides?
rashes, dermatolic reactions
-monitor potassium, serum creatinine, and CBC
57
what is the mechanism of action of tetracyclines?
inhibit protein synthesis at the ribosome (statcic)
58
what is the most commonly prescribed tetracycline?
doxycycline
59
what are some ADEs of tetracyclines?
tooth discoloration (in children under 8), esophagitis (take with a full glass of water and sit up for at least half hour otherwise it can errode your esophagus, nausea, and photosensitivity
60
which drugs are not used for tick borne illness?
tetracyclines
61
Which drugs are not given to pregnant women to not disrupt dentition of children in utero?
tetracyclines
62
when in doubt
doxy it out (given to treat odd infection if they can't figure out the infection)
63
glycopeptides and lipoglycopeptides are used for gram ___ infections
positive
64
vancomycin is used to treat which MDRO?
MRSA
65
what drug class does vancomycin fall under?
glycopeptides
66
describe some characteristics of vancomycin
-vitamin v
-mostly concentration dependent
-dosed in a patient specific manner
-Red man syndrome (not an allergy; infuse the drug slowly to prevent)
-harsh on kidneys
67
Which drugs are lipoglycopeptides?
dalbavancin and oritavancin
68
what are some characteristics of dalbavancin and oritavancin?
-longer half life
-1-2 dose treatment for skin infections
-can avoid hospital admission for IV treatment
-not always sure how to use them because they are newer
69
what does Linezolid treat and what must be monitored?
-gram positive and VRE
-Monitor platelets (patients are at risk of bleeding) and serotoninergic interactions
70
what does Daptomycin treat and what must be monitored?
-gram positive and VRE
-monitor CPK and statin use
-CPK can cause muscle pain and urine discoloration if it builds up in blood too much
71
What does Clindamycin treat?
-gram positive mostly
-some gram negative anaerobes
-causes antibiotic associated diarrhea and c. diff
72
Are IV drugs normally cidal or static?
cidal
73
true or false. Linezolid is an oral option for MRSA?
True
74
The use of what other drug may be discontinued when a patient takes daptomycin?
statin use
75
which drug is the second line agent after vancomycin?
daptomycin
76
what are 4 oral MRSA options?
-bactrum (sulfamethoxozole/trimethoprim)
-doxy
-clinda
-linezolid
77
what is Metronidazole used to treat?
-anaerobes (mostly gram negative)
78
what are some characteristics of Metronidazole?
-metallic taste
-cause nausea and vomiting
-used to be for c. diff, now only in combo if fulminant
79
What is nitrofuratoin used to treat?
UTIs
80
what are some side effects of nitrofurantoin?
-pulmonary toxicity
-not for use in elderly
81
Synercid is a combination of which drugs? how is it adminstered?
-clinda and delphaprstin
-horrible and causes flu like symptoms. obselete.
-can only be administered via central line and is very harsh on veins
82
What is an example of a glycyclcines
tigercycline (tygacil)
83
what is a side effect of glycyclines?
-increased mortality in pneumonia and bloodstream infections
-last line option
84
what are examples of polymixins?
polymistin B and colistin
85
what are polymixins used to treat?
only MDROs if they are used at all
86
what are adverse events associated with polymixins?
neurotoxicity and nephrotixicty
87
What information does an antibiogram provide?
-compile all isolates within the last year and describe susceptibility patterns
-provide a description of antimicrobial susceptibility for the community
-bacteria must be represented by a certain number of isolated to be reported
88
antibiograms are useful only for _____ selection
empiric
89
how much does antimicrobial resistance cost in expenditures yearly?
20 billion
90
how many unnecessary prescriptions are filed each year?
47 million
91
how many premature deaths are expected by 2050?
300 million
92
What are 4 mechanisms of antibiotic resistance?
1. enzymes
2. efflux pumps: bacteria vomits the antibiotic back out
3. target site alteration: fool the antibiotic, change so it can't bind and kill
4. decreased uptake: reverse channels; don't take up the antibiotic
93
which professionals are the core of antimicrobial stewardship?
ID trained MDs and PharmDs
94
define antimicrobial stewardship
the coordinated interventions designed to improve and measure the appropriate use of antimicrobials by promoting the selection of the optimal antimicrobial drug regimen, dose, duration of therapy, and route of adminstration
95
true or false. It is now legislated that all facilities have a formal stewardship program
True
96
what are the basic principles of antimicrobial stewardship?
right drug, dose, route, duration
97
when was MRSA first detected?
1960s
98
when was VRE first detected?
the 1980s in Europe and 90s in USA
99
when were ESBLs detected?
1990s
100
Define antimicrobial
a substance that inhibits or kills microbes
101
define antibiotic
a type of antimicrobial that is synthesized by a living microorganism, usually a fungus
102
how are most antimicrobials administered?
IV or oral
103
what is the MIC?
the lowest concentration of drug that can still inhibit microbial growth
104
what is half-life
how long the body takes to metabolize half of a drug
105
what is concentration dependent activity?
achieving a higher concentration in the blood over a short time is more effective at eliminating infection than maintaining a lower concentration over a longer period.
106
what is the goal of concentration dependent drugs?
maximize serum or tissue drug concentrations (often allows for once daily dosing)
107
what are examples of concentration dependent drugs?
-aminoglycosides
-fluoroquinolones
108
what is time-dependent activity?
maintain drug concentrations above the MIC. Lower doses at an increased frequency over time.
109
what are examples of time-dependent drugs?
-natural penicillins
-vancomycin
-beta lactams
110
define in vitro
lab susceptibility testing
111
define in vivo
patient
112
antibiograms can help answer questions in what 2 main areas?
-clinical care
-infection prevention strategies
113
what does an antibiogram do?
simplifies multiple patients antimicrobial sensitivity information at an institution into a single number for pathogens of interest in an effort to monitor trends emerging in drug resistance.
114
how many isolates are need for an antibiogram?
at least 30
115
For patients with multiple positive cultures, how many isolates should be included in an antibiogram?
Only the first (regardless of body fluid tested or antimicrobial susceptibility pattern)
116
can surveillance isolates be used for antibiograms?
no, only diagnostic
117
When developing an antibiogram for s. aureus, should MRSA be included?
Yes
118
True or false. Antibiograms do not underestiminate the activities of drugs for multi-drug resistant strains?
False
119
What are some methods of antimicrobial susceptibility testing?
-agar disk diffusion (Kirby-Bauer)
-antimicrobial gradient diffusion method (e-test or d-test)
120
How is the spread of resistance expressed?
as episodes of newly detected colonization or infection per 100 admissions or 1000 patient days
121
What is the main selective pressure responsible for antimicrobial resistance?
antimicrobial use
122
How do patients come to possess a resistant pathogen?
by transmitting bacteria that already have a resistance gene in place or by having the bacteria acquire a gene that codes for resistance
123
cidal agents kill _____% while static kills ___%
99.9%; 90-99%
124
when a drug is cidal or static can depend on what?
the concentration a pathogen is exposed to
125
what are some types of toxicities that may occur as a result of taking drugs?
-hepatotoxicity
-myelosupression
-renal toxicity
-auditory toxicity
-vestibular toxicity
-CNS toxicity
126
what are 3 indications for antimicrobial use?
1. empiric
2. pathogen directed
3. prophylactic
127
define prophylactic
Prevents rather than treats known or suspected infection
128
what is the most common prophylaxis?
surgical antimicrobial prophylaxis where wound infection risk is high. For prostetic devices and patients with immunosuppresion
129
what are some basic principles of antimicrobial prophylaxis?
-drug spectrum should be appropriate for the organisms likely to cause infection
-usually staph or strep
-adueqate tissue levels, usually 1st gen cephlasporin, should be used from first incision onward
-duration should be as short as necessary to minimize resistance, side effects, and costs
130
when should antimicrobial prophylaxis be considered?
-anytime skin or mucosa is incised
-patients travelling to areas with endemic malaria
-endocarditis in ptients with high risk valvular lesions
-spontaneous bacterial peritonitis in patients with ascites
131
What are 2 organisms where prophylaxis may be used?
-meningococcal meningitidis
-HIV
132
What dosage is normally required for propphylaxis?
a single preoperative dose and sometimes one or two additional doses is surgery duration is prolonged
133
What is empiric therapy?
When no definitive information about a causative pathogen is available, therapy is empiric
134
When is empiric therapy done?
when the results of cultures are pending. Patients are usually sufficiently ill at this time.
135
When are cultures collected for empiric therapy?
Before therapy is started
136
What directs empiric therapy?
site of infection and host factors (i.e., immunocomprised) give an indication of likely pathogens which can direct empiric therapy.
137
Does a NAAT (PCR) provide susceptibility results?
No, a culture needs to be done for this
138
True or false. Nonculture results can direct therapy for pathogen with predictable susceptibility?
True (i.e., chlamydia and gonorrhea)
139
Which factors contribute to successful antimicrobial therapy? (hint: there are 5)
1. prompt institution of an appropriate antimicrobial
2. The bug factor (virulence and susceptibility)
3. The drug factor (activity of the antimicrobial at a particular site of infection)
4. Host factor (underlying condition and patient immunocompetence)
5. site factor (infections at certain body sites like the heart are more difficult to treat)
140
Dose should be ___enough to be therapeutic but ___ enough to minimize toxicity
high; low
141
Hepatic insufficiency requires dose reduction of drugs excreted by the
Liver
142
Define switch therapy
switch from IV to oral after initial response to therapy
143
What are 3 possible effects of co-administering antimicrobials?
1. some inactivate others (piperaccilin/tazobactam and aminoglycosides)
2. Antigonism: inactivatoin. two antimicrobials become less effective (tetracycline and penicillin).
3. Synergy: two co-administered antimicrobials are more effective
144
What is an example of a synergetic drug combination
endocarditis due to enterococcus. Protein inhibitory agent (aminoglycoside) with a cell wall active agent (penicillin or vancomycin) to achieve bactericidal activity
145
describe the microtiter brother dilution systems
trays of small volume wells consisting of various concentrations of antibiotic read with an automated commercial instrument
146
describe the antimicrobial gradient diffusion method (e-test or d-test)
a regent strip of gradient antimicrobial is placed on an agar plate to produce a gradient of concentrations in the medium
147
results of antimicrobial susceptibility testing should be based on what
susceptible, intermediate susceptible (drug is only effective at body sites where it is concentrated) and resistant
148
what are some mechanisms of antimicrobial resistance?
-drug inactivation and alteration in target site
-decreased permeability or efflux
-bypass of a metabolic pathway
-point mutations in genes or acquisition of new genes
149
most forms of resistance result from
newly acquired genes
150
Which organism has become resistant through decreased permeability or efflux?
pseudomonas resistant to carbapenems
151
Which organism has become resistant to drugs through bypass of a metabolic pathway
trimethoprim/sulfamethoxazole
152
What are mutations
random errors that occur during DNA replication resulting in the ubstitution of one base pair for another which may result in the subtitution of one amino acid for another in a protein structure or enzyme. Mutations occur infrequently at the correct location at the bacterial genome to cause mutation.
153
ESBLs are resistant to all ______ except ____
beta-lactams except carbapenems
154
Define antibiotic cycling
alternate using different antimicrobials to prevent resistance
155
audits of the AS program can be ____ or _____
prospective or retrospective
156
What of the AS program can be audited?
-dosing
-whether surgical prophylaxis is used appropriately
-whether empiric is switched to pathogen directed therapy once culture results are available
157
What is the goal of antimicrobial stewardship?
optimize antimicrobial treatment that results in the best outcome with minimal toxicity to the patient
158
True or false. Antimicrobials are the only pharmaceutical therapy whose effectiveness dimishes with time and use.
True
159
How many deaths and illnesses annually are attributed to AMR?
23,000 deaths; 2 million illnesses
160
how many ER visits are due to an adverse antimicrobial reaction?
1 in 5 (140,000)
161
on average ______ of LTC residents will be taking antibiotics at any given time
6-10%
162
studies show that ____ of antibiotic prescribing may be unecessary
40-75%
163
ASP programs have been shown to
-improve patient outcomes
-reduce antimicrobial age related adverse events
-decrease antimicrobial resistance
164
up to ___ of nursing home residents received one or more courses of systemic antibitoics in a year
70%
165
what are the 7 core elements of antibiotic stewardship?
1. leadership
2. accountability
3. drug expertise
4. action
5. tracking
6. reporting
7. education
166
describe leadership
-ASP efforts in written statements and sharing this with staff, residents, and families
-including ASP duties in positions for medical director, pharmacists, and nursing leader
-communicate prescription policies
-supporting a culture and activities that promote ASP
167
describe accountability
identify and appoint individuals responsible for ASP activities
168
describe drug expertise
estbalish relationships with pharmaicsts or other individuals with ASP training or experience:
-ID docs
-ASP leads in hospitals within the network
169
describe action
requiring an ab timeout for all new ab starts
-improving the evaluation and communication of signs and symptoms when infection is first suspected (SBAR tool)
170
describe tracking
-montior at least one process and outcome measure of antibiotic use
-determine if antibiotics are prescribed per policy
-tracking antibiotic usedto review patterns and determining the impact of stewardship efforts.
outcome measures include: days of therapy, antibitoics starts, and prevalence surveys
-monitoring clinical outcomes
171
describe reporting and education
-reporting: provide regular feedback on antibiotic use and resistance to relevant staff
-education: provide resources to everyone about resistance and opportunities to improve use
172
what are some harms associated with antimicrobial prescribing
-anaphylaxis
-c. diff
-oral and vaginal superinfection (due to disruption of flora)
-adverse drug reactions
-increased healthcare expenditures
-resident and family suffering
-potential heavier work burden
-unecessary diagnoatic testing
-toxicity
-unfaovrable perception of a facility with increased infection rates
-related costs and burdens of adding TBP
-increased risk of MDRO colonization and infection
173
MDRO/ARO infections could result in what compared to susceptible infections?
-greater morbidity and mortality
-extended hospitalizations
-greater use of healthcare resources
-prolonged and costlier treatments
174
What are the 4 moments for antimicrobial decision making?
-1. make the diagnosis
2. cultures and empiric therapy
3. duration of therapy
4. stop, narrow, change to oral
175
define contamination
the introduction of undesired microbes or toxins to a specimen, the environment, or equipment (i.e., urine C & S with mixed growth).
176
where does VRE colonize?
GI/ GU tract
177
where does ESBL colonize?
GI/GU tract
178
where does c. diff colonize?
the GI tract
179
contamination is common associated with improper specimen collection such as:
1. urine culture (not utilizing clean catch or sterile collection)
2. wound swabs: taking a specimen from necrotic, exudate, or eschar rather than wound bed
3. blood cultures: improper cleaning of skin or top of collection containers
180
define cross contamination
part of one specimen is transferred into another (occurs if samples are improperly stored, have cracks, or are improperly handled)
