Antimicrobial Therapy Flashcards
1
Q
Goals and general rules
A
- inhibit microorganisms at concentrations that are tolerated by the host
- seriously ill/immunocompromised select bactericidal
- narrow spectrum before broad spectrum or combo therapy to preserve normal flora
2
Q
Potential adverse reactions
A
hypersensitivity, direct organ toxicity, superinfection, cross-reactions with other medications
3
Q
SSI (surgical site infections) are ___ most common healthcare associated infection
A
second
4
Q
SSIs develop in ___ % of 30 million surgical patients
A
2-5%
5
Q
SSIs represent approximately ____ % of all hospital acquired infections annually in the US
A
14-16%
6
Q
SSIs lead to
A
- increased readmits
- increased length of stay (7-10 days)
- increased hospital costs
7
Q
SSI definition
A
infection related to a operative procedure that occurs at or near the surgical incision within 30 days of the procedure
8
Q
Characteristics of SSIs
A
- purulent exudate from surgical site
- positive culture from surgical site that was closed initially
- surgeon’s diagnosis of infection
- surgical site that requires reopening d/t at least one s/s: tenderness, swelling, redness, or heat
9
Q
Surgical risks for developing SSI
A
- procedure type
- skill of surgeon
- use of foreign material or implantable device
- degree of tissue trauma
10
Q
Patient risks for developing SSI
A
diabetes, smoking use, obesity, malnutrition, systemic steroid use, immunosuppressive therapy, intraop hypothermia, trauma, prosthetic heart valves
11
Q
How does hypothermia put someone at risk of developing a SSI?
A
decreases basal metabolic rate and constricts blood vessels
it makes the blood more viscose and causes a shift on the curve to the left (hold onto O2)
left = love O2
12
Q
SSI Prevention Measures
A
- Surgical Care Improvement Project (SCIP)
- timely and appropriate use of antibiotics
- maintenance of normothermia
- proper syringe/med administration practices
13
Q
SCIP Inf-1
A
prophylactic antibiotic received w/in one hour prior to incision
14
Q
SCIP Inf -2
A
prophylactic antibiotic selection for surgical patients
15
Q
SCIP Inf-3
A
prophylactic antibiotics discontinued w/in 24 hours after surgery end time
16
Q
SCIP Inf-4
A
cardiac surgery patients with controlled 6am postop blood glucose
17
Q
SCIP Inf - 6
A
surgery patients with appropriate hair removal
18
Q
SCIP Inf - 9
A
Urinary cath removed on postop day 1 or 2 w/ day of surgery being day 0
19
Q
SCIP Inf - 10
A
surgery patients w/ periop temp management
20
Q
SCIP Card - 2
A
on beta blocker therapy prior to arrival who received beta blocker during periop period
21
Q
SCIP VTE -1
A
surgery patients with recommended VTE prophylaxis ordered
22
Q
SCIP VTE -2
A
received appropriate VTE prophylaxis w/in 24 hours prior to surgery to 24 hours after surgery
23
Q
Ideal window for drug administration
A
30-60 minutes before incision
24
Q
hypothermia is associated with
A
- increased blood loss
- increased transfusion requirements
- prolonged PACU stay
- postop pain
- impaired immune function (compromised neutrophil = vasoconstriction = tissue hypoxia)
25
Subacute Bacterial Endocarditis (SBE) Prophylaxis
standard:
amoxicillin 2 g PO
ampicillin 2g IV
penicillin allergy:
clindamycin 600 mg IV
cefazolin 1 g IV (not in pts. w/ hypersensitivity to PCN)
26
Appropriate antibiotic for cardiothoracic and vascular surgery
cefazolin, cefuroxime, vancomycin
| if B lactam allergy - vancomycin or clindamycin
27
Appropriate antibiotic for hysterectomy
cefotetan, cefazolin, cefoxitin, cefuroxime, ampicillin/sulbactam
if B lactam allergy - clindamycin + gentamycin or metronidazole + gentamycin or clindamycin alone
28
Appropriate antibiotic for hip or knee arthroplasty
cefazolin or cefuroxime
| if B lactam allergy - vancomycin or clindamycin
29
Appropriate antibiotic for colon surgery
cefotetan, cefoxitin, cefazolin + metronidazole, ampicillin/sulbactam
if B lactam allergy - clindamycin + gentamycin or metronidazole + gentamicin
30
where might we use gentamycin over cefazolin?
in urology procedures
31
Staphylococci pathogens are common in which procedures and what is it treated with?
cardiac, noncardiac/thoracic, vascular, neuro, ortho
cefazolin!
32
Enteric gram negative rods are common pathogens in which procedures
cardiac, noncardiac/thoracic, vascular, gastroduodenal, biliary tract, colorectal, appendectomy, hysterectomy, c section
33
Streptococci pathogens are common in which procedures
noncardiac/thoracic, hysterectomy, c section
34
S aureus and oral flora are common pathogens in which procedures
head and neck, gastroduodenal, biliary tract
35
Enterococci are common pathogens in which procedures
biliary tract, hysterectomy, c section
36
Anaerobes are common pathogens in which procedures
colorectal, appendectomy, hysterectomy, c section
37
Group B streptococci pathogens are common in which procedures
hysterectomy, c section
38
Bactericidal
kill the susceptible bacteria
usually what the OR uses
give to immunosuppressed patients
39
Bacteriostatic
reversibly inhibit the growth of bacteria
have to be on medication long enough so body can develop a response
for UTIs usually
40
Types of bactericidals
penicillins, cephalosporins, isoniazid, metronidazole, polymyxins, rifampin, vancomycin, aminoglycosides, bacitracin, quinolones
41
types of bacteriostatics
chloramphenicol, clindamycin, macrolides, sulfonamides, tetracyclines, trimethoprim
42
penicillin basic structure
dicyclic nucleus that consists of a thiazolidine ring connected to a B lactam ring
43
Penicillin MOA and organisms it acts on
inhibits the enzyme needed to keep bacteria wall
| organisms: pneumococcal, meningococcal, streptococcal, actinomycosis
44
Penicillin excretion, DOA, and adverse reactions
excretion: renal (anuria increases elimination 1/2 time by 10x)
DOA: probenecid (gout med) will reduce renal excretion and prolong action so decrease PCN dose
adverse: hypersensitivity (most allergenic), cross sensitivity (d/t B lactam ring), rash/fever, hemolytic anemia, maculopapular rash
45
Penicillin uses
otitis media, meningitis, sore throat, pneumonia and respiratory infections, septicemia, peritonitis, gonorrhea, UTIs
46
Second generation penicillins and advantages/disadvantages
amoxicillin and ampicillin
advantage: wider range of activity (gram negative bacilli, H. influenza, ecoli)
disadvantage: more expensive
47
Cephalosporins (Cefazolin aka Ancef)
```
bactericidal
inhibit bacterial cell wall synthesis
low toxicity
broad spectrum
renal excretion
penetrates joints and placenta
```
48
1st generation cephalosporins
cover mostly strep pneumoniae and gram positives.. some coverage of gram negatives
example: cefazolin
49
2nd generation cephalosporins
even coverage of gram negatives, gram positives, and strep pneumoniae
example: cefoxitin
50
3rd generation cephalosporins
cover mostly against gram negatives and strep pneumoniae; some coverage of gram positives
example: cefotaxime
51
4th generation cephalosporins
covers mostly gram negatives and strep pneumoniae, good coverage of gram positives
example: cefepime
52
which cephalosporin generation is best for meningitis?
3rd generation
achieve therapeutic levels in the CSF
lower toxicity than earlier generations
53
patients with IgE mediated anaphylactic reactions to B lactam antibiotics can be given ___ in substitution
clindamycin or vancomycin
54
Macrolide - (Erythromycin)
effective against gram + bacilli, penumococci, streptococci, mycoplasma, chlamydia
bacteriostatic or bactericidal (depends on organism and dose)
inhibits bacterial protein synthesis
metabolized by CYP450 system so will increase serum concentration of theophylline, warfarin, cyclosporine, methylprednisone, and digoxin
excreted in bile
don't need to alter with renal disease
55
Erythromycin uses and side effects
uses: otitis media, uncomplicated skin infections, ulcers, pneumonia, MAC, legionnaire's, anthrax, pharyngitis, tonsillitis, sore throat, STDs (Chancroid, chlamydia, gonorrhea)
s/e: GI intolerance, N/V, increase gastric emptying, cholestasic hepatitis, prolongs repolarization, torsades, thrombophlebitis
56
Clindamycin
linomycin
bacteriostatic
active with anaerobes
can cause pseudomembranous colitis (discontinue if occurs)
decrease dose with severe liver disease
use: female GU surgeries, oral infections, lung abscess and aspiration pneumonia, MRSA soft tissue, nec fasc
s/e: skin rash, prolonged pre and post junctional effects at NMJ
concurrent use with NDMR can produce long lasting and profound blockade
57
Vancomycin
glycopeptide
bacteriocidal
impairs cell wall synthesis
gram positive bacteria
renal excretion
elimination 1/2 time 6 hours
uses: severe staph infection, strepto/enterococcal endocarditis, MRSA***, PCN/cephalosporin allergy, cardiac/ortho surgeries using prosthetic devices, CSF and shunt related infections
dose: 10-15mg/kg over 60 minutes; 1 g mix in 250mL
*profound hypotension if given rapidly!!*
can cause red man syndrome (erythema), ototoxicity, nephrotoxicity
58
what can you give prior to vancomycin administration to limit histamine release?
diphenhydramine 1 mg/kg and cimetidine 4mg/kg 1 hour before
59
Amikacin
derivative of kanamycin
| treatment for infections caused by gentamycin or tobramycin resistant gram negative bacilli
60
which aminoglycoside is most nephrotoxic?
neomycin
61
toxic level of gentamicin
>9 mcg/mL
62
aminoglycosides
bactericidal
effective for aerobic gram - and + bacteria, mycobacterium tuberculosis
combo with B lactam antibiotic for gram -
2-3 hour elimination 1/2 time increased 20-40x with renal failure
s/e: oto/nephrotoxicity, muscle weakness
63
IV admin of aminoglycosides is associated with
potentiation of nondepolarizing neuromuscular blocking drugs
can be reversed with calcium gluconate or neostigmine
some people could be reparalyzed after reversal!
64
fluoroquinolones
broad spectrum
bactericidal
effective: enteric gram - bacilli, mycobacterium, GI/GU infections, bone, soft tissue, respiratory tract systemic infections, opthalmic infections
can inhibit P450 enzymes
s/e: GI, n/v, dizziness, insomnia, tendon or achilles rupture!, muscle weakness
65
ciprofloxacin uses
respiratory infections, tuberculosis, anthrax
66
moxifloxacin
use: long acting treatment of acute sinusitis, bronchitis, complicated abd infections
s/e: QT prolongation, peripheral neuropathy, psychosis, stevens-johnson syndrome
67
sulfonamides
bacteriostatic
prevent normal use of PABA by bacteria to synthesize folic acid
inhibit microbial synthesis of folate production
uses: UTIs, inflammatory bowel disease, burns
s/e: skin rash, photosensitivity, nephritis, fever, hepatotoxicity, hemolytic anemia, thrombocytopenia, increase effect of PO anticoag
68
metronidazole
bactericidal
use: anaerobic gram - bacilli clostridium, CNS infections, abd and pelvic sepsis, c diff, endocarditis
recommended preop prophylaxis for colorectal surgery!
s/e: dry mouth, metallic taste, nausea, avoid alcohol
69
amphotericin B
```
antifungal
yeast and fungi
poor PO absorption (give IV)
renal function is impaired in 80% of pts
monitor plasma creat
s/e: fever, chills, dyspnea, hypotension, impaired hepatic, hypokalemia, seizure, anemia, thrombocytopenia
```
70
antimycobacterial agents
isoniazid, rifampin, ethambutol, pyrazinamide
71
when patients are on antiretrovirals CRNAs should note
existence of adverse effects (liver toxic, peripheral neuropathy, nephrotoxic, neuromuscular weakness)
interactions with other meds (PPIs, cimetidine, NDMR, opioids, benzos)
72
6 classes of antiretrovirals
```
nucleoside/non nucleotide
protease inhibitors
fusion inhibitors
CCR5 receptors
integrase inhibitors
```
73
antiviral side effects
flu like symptoms, hematologic toxicity, depression, irritable, decreased mental concentration, autoimmune condition development, rash, alopecia, changes in CV, thyroid, and hepatic function
74
acyclovir
treat herpes
may cause renal damage if given rapidly
can cause thrombophlebitis
may complain of HA during infusion
