Antimicrobials Flashcards

1
Q

beta lactam abx

A

penicillins
cephalsporins
carbapenems

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2
Q

Risk for SSI: surgical risk

A

procedure type
skill of surgeon
use of foreign material or implantable device
degree of tissue trauma

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3
Q

Risk for SSI: patient risks

A
diabetes - vascular disease
smoking use - dramatic decrease in SSI if cessation 4-8 wks prior
obesity
malnutrition
systemic steroid use (not proven)
immunosuppressive therapy
intraoperative hypothermia
trauma
prothetic heart valves
extremes of age
hair removal - dont shave
preop hospitalization
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4
Q

Anesthesia provider can make an impact on SSI prevention though:

A

timely and appropriate use of ABX
maintenance of normothermia
proper syringe/med admin practices
periop glucose control

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5
Q

Hypothermia is associated with:

A
increased blood loss  - coagulation cascade doesn't work as well
increased transfusion req
prolonged pacu stay
post op pain
impaired immune function

compromised neutrophil function –> vasoconstriction –> tissue hypoxia and increased incidence of SSI

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6
Q

Microbial resistance to anti-microbials: mechanisms

A
  • increase active transport (of ABX) out of bacteria and/or decrease active transport (of ABX) into the cell
  • structural changes in drug target (mutations)
  • production of a drug ABX antagonist
  • enzymatic drug destruction (beta lactamase)
  • the more ABX are used the more resistance develops (in target bacteria and normal flora)
  • ABX are used extensively in hospitals
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7
Q

Antimicrobials and Anesthesiology: Goals and General Rules

A
  1. inhibit microorganisms at conc that are tolerated by the host (don’t want to give so much that we cause 1) end organ toxicity 2) unacceptable SE)
  2. MIC = minimum conc that we need to keep infection at bay –> allow its immune system to do its thing
  3. seriously ill/immunocompromised select bactericidal
  4. narrow spectrum before broad spectrum or combination therapy to preserve normal flora
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8
Q

beta lactams: MOA

A

WEAKEN BACTERIAL CELL WALL

–bind to penicillin binding proteins (only expressed during bacterial proliferation)

  1. activate autolysins (decrease inhibition of muerin hydrolase - enzymatic destruction of cell wall)
  2. inhibit (transpeptidases) enzyme needed for cell wall synthesis and integrity (of cross bridges)
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9
Q

Penicillin binding protein

A

required for entry of ABX into cell

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10
Q

beta lactamase

A

enzyme that will destroy beta lactam ring - could make an ABX uselss for targeting that bacteria

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11
Q

Patients with documented IgE mediated anaphylactic reactions the beta lactam ABX can be substituted with?

A

clindamycin or vancomycin

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12
Q

Principle concern of Penicillin

A

Allergic reactions - most common cause of drug allergy (incidence 1-10%)

Anaphylaxis (.004 - .04% with 10% mortality)

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13
Q

Penicillin: Excretion

A

Rapid renal excretion - plasma conc decreases 50% in 1st hour (short half life)

anuria increases elimination half time by 10 fold

DOSE ADJUST IN RF

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14
Q

Administration of probenicid with Penicillin.

A

admin of penicillin with probenicid will reduce renal excretion and prolong action

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15
Q

Broad spectrum penicillin: second generation

A

amoxicillin

ampicillin

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16
Q

Ampicillin excretion

A

50% excreted unchanged by the kidney 6 hours after admin

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17
Q

Carbenicillin: effects and anesthesia considerations

A

broad spectrum penicillin: 3rd generation

E1/2time: 1 hour (2 hrs renal disease)
85% excreted unchanged by kidney
high sodium load -- CAUTION IN HF
hypokalemia
metabolic alkalsosis
prolonged bleeding despite normal platelet count

ANESTHESIA CONSIDERATIONS
Preoperative:
lower threshold for BMP, ABG, platelets/CBC, more aggressive about blood availability

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18
Q

beta lactamase resistant penicillins: agents and use

A

nafcillin
–penetrates CNS; 80% secreted in the bile/GOOD FOR PATIENTS WITH RENAL DYSFUNCTION

dicloxacillin

oxacillin

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19
Q

beta lactamase resistant penicillins: MOA

A

binds irreversibly to b lactamase enzymes

-large side group sterically hinders beta lactamase from cleaving beta lactam ring

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20
Q

beta lactam/beta lactamse inhibitor combinations: agents and spectrum

A

unasyn (ampicillin/sulbactam)
augmentin (amoxicillin/clavulanic acid)
timentin (ticarcillin/clavulanic acid)
zosyn (pip/taz)

broadest spectrum agents

  • gram positive
  • gram negative activity
  • anerobes
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21
Q

Cephalosporins: MOA, therapeutic index

A

favorable therapeutic index (low toxicity, highly effective)

WEAKEN BACTERIAL CELL WALL

–bind to penicillin binding proteins (only expressed during bacterial proliferation)

  1. activate autolysins (decrease inhibition of muerin hydrolase - enzymatic destruction of cell wall)
  2. inhibit (transpeptidases) enzyme needed for cell wall synthesis and integrity (of cross bridges)
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22
Q

Cephalosporins and beta lactamase susceptibility through generations

A

b lactamase susceptibility decrases as you move from 1st to 4th gen

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23
Q

cephalosporins and gram activity through generations

A

1st and 2nd gen: gram pos activity, don’t cross BBB, not active against gram neg

3rd and 4th gen: quite broad, gram neg activity & activity against anaerobes & ability to penetrate the BBB

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24
Q

Broadest cephalosporin

A

4th generation cephalosporin: cefepime

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25
Q

Ceftaroline

A

5th (or 3rd) generation cephalosporin

MRSA COVERAGE

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26
Q

Cephalosporins: Elimination + exception to rule

A

primarily renal (DOSE REDUCTION IN RENAL DISEASE)

exception: ceftriaxone - sig hepatic metabolism, also, longest E 1/2 of 3rd gen

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27
Q

Cefazolin: Cautions/CI

A

crosses the placenta
allergy incidence 1-10%
cross reactivity with other cephalosporins
Penicillin/cephalosporin cross reactivity: 1%
RENAL EXCRETION

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28
Q

Cephalosporins: Adverse Effects

A
  • bleeding (cefoperazone, cefotetan, ceftriaxone)
  • –inhibit conversion of vitamin K to active form
  • –CHECK PT/INR
  • thrombophlebitis (IV site) - uncommon
  • hemolytic anemia - very rare
  • superinfection (c diff) - risk the more broader spectrum you go
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29
Q

Cephalosporins: Drug Interactions

A

-probenacid (prolong DOA by delaying elimination)

  • ETOH (cefazolin, cefmetazole, cefoperazone, cefotetan)
  • -disulfiram like reaction

-anticoagulants/anti-plt dugs (cefoperzone, cefotetan, ceftriaxone)

  • calcium + cefitriaxone: fatal precipitates –> NO LR
  • –especially with neonates
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30
Q

Ceftriaxone considerations

A
  • sig hepatic metabolism
  • 33-67% excreted unchanged in urine
  • longest E1/2t of 3rd gen
bleeding risk (prevents active form of vit K)
DI with anticoag/anti-platelet

fatal precipitates with calcium (NO LR)

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31
Q

Azetreonam (Azactam): Class and MOA

A

Monobactam

Cell wall agent

  • inhibits cell wall synthesis = cell lysis and death
  • has a high affinity to a specific PBP (PBP3) in gram neg bac only

highly resistant to beta lactimases

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32
Q

Azetreonam (Azactam): SE profile, PK

A

few adverse effects
Excreted unchanged by kidney
E1/2t: 1.5 hours
most sig risk: GI superinfections

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33
Q

Good substitute for patient with a penicillin allergy

A

Azactam - cross reactivity is unlikely

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34
Q

Macrolides: MOA and agents

A

MOA: bind to a 50S subunit of the ribosome to block protein synthesis in bacterial cells - bacteriostatic

  • erythromycin
  • clarithromycin/biaxin
  • azithromycin/zithromax
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35
Q

ABX coverage against atypical pathogens.

A

MACROLIDES

community acquired PNA
legionella pneumophilia (legionnaire's disease)
pertussis
acute diptheria
chlamydial infections
bacterial endocarditis
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36
Q

Macrolides: Side Effects

A
  • GI intolerance - most common side effect
  • severe N/V can occur with infusion
  • may slow gastric emptying - inc asp risk
  • cholestatic hepatitis
  • IV formulation associated with tinnitus and hearing loss
  • thrombophlebitis
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37
Q

Macrolides: metabolism

A

metabolized by CYP3A4 - can inc serum conc of:

  • theophylline
  • warfarin
  • cyclosporine
  • methylprednisone
  • digoxin

excreted mostly in bile –> GOOD FOR RENAL DISEASE (no need to alter dose in renal disease)

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38
Q

Macrolides: QT effects

A

PROLONGS QT - prolongs cardiac repolarization

reports of torsades

CYP3A4 inhibitors can inc plasma concentrations and increase risk of fatal vent dysrhythmias

  • -verapamil
  • -diltiazem
  • -protease inhibitors
  • -azole antifungals

5x inc in sudden cardiac death when ERYTHROMYCIN and CYP3A4 inhibitor are prescribed together

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39
Q

Clindamycin: Class and MOA

A

Linomycin

MOA: blocks protein synthesis by binding to 50S ribosomal subunit - usually bacteriostatic

similar to erythromycin in antimicrobial activity, but more active with anaerobes

commonly used in female GU

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40
Q

Clindamycin: adverse effects AND anesthesia considerations

A
  • pseudomembranous colitis –> severe diarrhea should indicate d/c of therapy - CONSIDER FLUID/ELEC BALANCE
  • skin rash/hypersensitivity
  • blood dyscrasias (eosinophilia, leukopenia, thrombocytopenia - LOWER THRESHOLD FOR GETTING CBC
  • PROLONGED PRE AND POST JUNCTIONAL EFFECTS AT NMJ IN THE ABSENCE OF NDMR
  • -concurrent admin with NDMR can produce long lasting, profound NMB
  • -not antagonized with anticholinesterases or calcium!
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41
Q

Clindamycin: metabolism

A

Only 10% excreted unchanged in urine

DOSE DECREASE IN LIVER DISEASE

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42
Q

Vancomycin: Class and MOA

A

Glycopeptide

MOA:

  • inhibits bacterial cell wall synthesis = cell lysis and death
  • binds and inactivates cell wall precursors
  • bactericidal - “slowly cidal”
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43
Q

Vanc: uses

A
  • synergistic with aminoglycosides - vanc increases access of aminoglycosides to actual site of action (aminoglycosides inhibit 30S subunit of ribosome)
  • activity against MRSA
  • good choice in severe PCN allergy patients
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44
Q

Vanc: Dosing

A

10-15 mg/kg SLOWLY over 60 minutes
1 gram mixed in 250 ml
(fast admin carries risk of “red man syndrome” –> profound hypotension)

*12 hours of therapeutic plasma conc**

DOSE ADJUST FOR RENAL INSUFFICIENCY

45
Q

Vanc: metabolism/excretion

A

DOSE ADJSUT FOR RENAL INSUFFICIENCY
renal excretion: 90% unchanged in urine

E1/2t: 6 hours (can be prolonged up to 9 days with RF)

poor PO absorption (exception: PO for intestinal infection)

46
Q

Vanc: drug interactions

A

other nephrotoxic drugs

  • dye
  • NSAIDs
  • toradol
  • ampho b
  • cyclosporine

synergistic nephrotoxicity with aminoglycosides

47
Q

Vanc: side effects

A
  • thrombophlebitis (irritating to tissue)
  • nephrotoxicity (renal failure) - rare unless coadmin with other nephrotoxic drugs
  • ototoxicity with conc > 30 mcg/ml (increased risk if coadmin with aminoglycosides)
  • hypersensitivity (macropapular skin rash)
  • “Red man syndrome” – severe hypotension (flushing due to histamine release) if give IV in < 30 min
  • –intense facial and truncal erythema from histamine release

–diphenhydramine 1 mg/kg and cimetidine 4mg/kg 1 hour before induction limits histamine related effects

-immune mediated thrombocytopenia and bleeding - rare

48
Q

Vanc: anesthetic preop lab considerations

A

creatinine - narrow therapeutic index

CBC - thrombocytopenia SE rare

49
Q

Aminioglycosides: MOA

A

Work on 30S ribosomal subunit
-block the initiation of protein synthesis/premature termination of protein synthesis/abnormal protein formation in bacterial cells

effective in mycobacterium TB

50
Q

Aminoglycosides: metabolism and elimination

A
  • really positively charged, highly water soluble - Vd = extracellular volume
  • extensive renal excretion through glomerular filtration (almost 100%)

E1/2t: 2-3 hrs (inc 20-40 fold in RF)

51
Q

Aminoglycosides: side effects

A
  • limited by their toxicity
  • cross the placenta and could cause harm (oto and nephrotoxicity in babe)
  • ototoxicity (tend to conc around ear)
  • —esp with diuretics, furosemide, mannitol
  • nephrotoxicity (tend to conc in kidney)
  • —esp with ampho b, cyclosporine, etacrynic acid, vanco, NSAIDs, ketorolac

SKELETAL MUSCLE WEAKNESS: inhibit pre junctional release of ach and decreases post synaptic sens to the neurotransmitter - consider MG pts
–profound blockade with NDNMB

52
Q

Amikacin: drug interaction

A

Aminoglycoside

do not use with penicillin (may antagonize PCN effects)

LITTLE KNOWN ANTIBIOTIC RESISTANCE

53
Q

Gentamicin: Class and toxic level

A

Aminoglycoside

> 9 mcg/ml

54
Q

Aminoglycosides and NDMR

A

IV admin of aminoglycosides associated with potentiation of NDNMB

paralysis usually reversible with calcium gluconate or neostigmine

55
Q

Linezolid (Zyvox): MOA and use

A

MOA: works on 23S subunit
inhibits bacterial protein synthesis by preventing the formation of a functional ribosomal subunit initiation complex that is essential for the bacterial translation process

can’t translate mRNA into protein

very important because its resistant to MRSA and VRE

56
Q

Linezolid (Zyvox): Adverse effects and anesthetic implications

A
  • thrombocytopenia, anemia, leukopenia, pancytopenia (esp > 2 wks of TX)
  • —-CBC CHECK
  • GI effects
  • —-MORE AGGRESSIVE ANTIEMETIC PLAN + FLUID/ELEC BALANCE
  • RARE: optic and peripheral neuropathy
  • —POSITIONING (think prone), NEURAXIAL ANESTHESIA
  • formulated w/ phenylalanine
  • —avoid in pts with phenylketonuria
  • weak MAOI: watch for additive NE and 5HT effects when used with other sertonergic agents and/or indirect sympathomimetics –> risk of serotonin sydrome & hypertensive crisis
  • —EPHEDRINE AND SSRIS CONTRAINDICATED
57
Q

Fluoroquinolones: MOA + use + agents

A

MOA: inhibits DNA gyrase and topoisomerase, which are critical bacterial enzymes used in DNA replication & cell division –> stop growth and proliferation of bacteria

Use: complicated GI and GU infections, respiratory tract, TB, anthrax

ciprofloxacin (cipro)
levofloxacin (levaquin)
moxifloxacin (avelox) - higher risk of adverse effects

58
Q

Fluoroquinolones: Adverse effects

A
  • class warning for QT PROLONGATION
  • nausea
  • CNS disturbances
  • opportunistic candida
  • rashes
  • photo-toxicity (severe sunburn)
  • muscle weakness in MG pts
  • tendinitis and achilles tendon rupture due to extracellular cartilage matrix weakening
  • -highest risk > 65 yo, corticosteroid use, s/p transplant
  • -avoid IV form <18 yo - rare, but still growing
59
Q

Fluoroquinolones: drug interactions

A

CYP450 interactions, increases levels of:
theophylline
warfarin
tinidazole

60
Q

Fluoroquinolones: Elimination

A

renal excretion through glomerular filtration and renal tubular secretion
–DECREASE DOSE IN RENAL DYSFUNCTION

E1/2t: 3-8 hours (pretty long)

61
Q

Sulfonamides (Bactrim, specifically): MOA and uses

A

MOA: prevent normal use of PABA by bacteria to synthesize folic acid; inhibit microbial synthesis of folate production
folic acid needed for nucleotide synthesis

Uses: UTIs, burns, inflammatory bowel disease

sulfamethoxazole and trimethoprim used synergistically because they effect different parts of biosynthetic pathway

62
Q

Bactrim: side effects

A
  • skin rash to anaphylaxis
  • photosensitivity
  • allergic nephritis
  • drug fever
  • hepatotoxicity
  • acute hemolytic anemia
  • thrombocytopenia
  • increase effect of PO anticoagulant
63
Q

Bactrim: metabolism and elimination

A

liver and kidney

portion of drug is acetylated in the liver and other is renally excreted

renal disease - DOSE REDUCTION

64
Q

Metronidazole: Use

A

rec for pre op prophylaxis for CRS

variety of infections: CNS, abdominal and pelvic sepsis, pseudomembranous colitis (c diff), endocarditis

well absorbed orally and widely distributed in tissue including CNS

65
Q

Metronidazole: side effects

A
  • dry mouth
  • metallic taste
  • nausea
  • avoid alcohol - disulfuram reaction
  • RARE: neuropathy and pancreatitis
66
Q

Isoniazid: anesthetic considerations

A

antimycobacterial agent - 1st line agent against TB

hepato - renal toxicity – PRE OP WORK UP

67
Q

Rifampicin: anesthetic considerations

A

antimycobacterial agent - 1st line agent against TB

hepatic enzyme induction – MAY HAVE TO DOSE ANESTHETIC DRUGS MORE FREQUENTLY

hepato - renal toxicity, thrombocytopenia, anemia - PREOP WORK UP (consider patient type and surgery type. Is this a pt with low O2 carrying capacity or CAD –> at risk for MI)

68
Q

Ethambutol: anesthetic considerations

A

antimycobacterial agent - 1st line agent against TB

optic neuritis - POSITIONING, HTN

69
Q

Pyrazinamide: anesthetic considerations

A

antimycobacterial agent - 1st line agent against TB

Liver toxicity - PRE OP WORK

70
Q

Amphotericin B: Class and MOA

A

Antifungal

MOA: binds to ergosterol (analagous to cholesterol, but not actually cholesterol) in fungal membranes to form pores –> altered membrane permeability causes leakage of cellular contents

71
Q

Amphotericin B: Elimination

A

Slow renal excretion

renal fxn impaired in 80% of pts treated with this drug - most recover after drug is stopped but some resulting permanent decrease in GFR may remain

MONITOR SERUM CREATININE

72
Q

Ampho B: side effects and anesthetic considerations

A
  • fever, chills, dyspnea, hypotension can occur during infusion
  • impaired hepatic function
  • hypokalemia - ELECTROLYTES
  • allergic reactions
  • seizure
  • anemia - CBC
  • thrombocytopenia - CBC

ANESTHETIC CONSDIERATIONS:

  • careful of anything that could be nephrotoxic
  • CBC
  • FLUID LOAD
  • ELECTROLYTES
73
Q

Viral life cycle

A
  1. absorption
  2. penetration
  3. uncoating
  4. viral genome replication (DNA or RNA)
    - -using host or viral polymerases
  5. maturation
  6. release
74
Q

Acyclovir: Class + MOA

A

Pro - drug activated by viral phophorylation by THYMIDINE KINASE

MOA: inhibits viral DNA synthesis

  • inhibition of DNA polymerase
  • insertion into viral DNA blocking the addition of subsequent nucleotides (block strand growth)
75
Q

Acyclovir: Uses

A

HSV&raquo_space;» VZV&raquo_space;» CMV&raquo_space;» mammalian

Uses: genital &herpes labialis, chicken pox (only if given within 24 hrs onset), shingles (high doses), and herpes encephalitis

CMV, EBV NOT SENSITIVE

76
Q

Acyclovir: PK

A

poor oral availability <20%
great distribution (CSF - 50% plasma conc)
Renal elimination: unchanged - DOSE REDUCE IN RF
E1/2T: 2.5 hours

77
Q

Acyclovir and pregnancy

A

SAFE IN PREGNANCY/BREASTFEEDING

78
Q

Acyclovir: adverse reactions

A
  • phlebitis (IV)
  • nephrotoxicity (IV/PO) - give over > 1 hour, HYDRATION IS IMPORTANT
  • neurotoxicity (IV); rare excitatory reactions, hallucinations, myoclonus, esp renal disease (RESEMBLES KETAMINE)
  • GI intolerance
79
Q

Ganciclovir: Precautions

A

mutagenic and carcinogenic!!!!!

80
Q

Ganciclovir: MOA and use

A

pro - drug: phosphorylated by CMV within cells; active triphosphate form inhibits viral DNA synthesis (inhibits DNA polymerase & incorporated into growing chain = premature chain termination)

Uses: CMV, pneumonitis, colitis, viremia, prophylaxis

81
Q

Ganciclovir: adverse effects

A
  • granulocytopenia (40%)
  • thrombocytopenia (20 %)
  • serum creatinine
  • –monitor levels and stop if absolute neutrophil ct or plt ct drop significantly

MONITOR CBC AND CREATININE

82
Q

Interferon A: use and MOA

A

Use: Hep C

interferons are signaling proteins made and released by host cells in response to viruses

blocks viral cell entry, decreases synthesis, of viral mRNA & proteins, vial assembly and release

83
Q

Interferon A: adverse effects and anes. considerations

A
  • flu like symptoms (PT MAY BE TAKING NSAIDS FOR SYMPTOMS AND THEY CAN’T BE TAKING THESE PRIOR TO SX SO THEY MAY FEEL KIND OF MISERABLE)
  • neuropsychiatric effects, esp depression
  • fatigue, thyroid dysfunction, heart damage (LOWER THRESHOLD FOR CV WORKUP, THYROID LABS)
  • bone marrow suppression (neutropenia, thrombocytopenia, may induce autoimmune disease) - (PRE OP CBC)
84
Q

Protease Inhibitors: Use and MOA

A

Tx of chronic hep c by inhibition of viral protease required for viral replication

85
Q

Protease Inhibitors: Adverse effects and anes. considerations

A
  • hepatoxicity (PRE OP LIVER LABS)
  • photosensitivity (severe sunburn)
  • severe rash (PRE OP SKIN ASSESSMENT)
  • contains sulfonamides (NO SULFA ALLERGY)
86
Q

Protease Inhibitors: drug interactions

A
  • amio (severe bradycardia)
  • reduce statin doses
  • inc benzo levels
87
Q

Protease Inhibitors: Metabolism and Elimination

A

Metabolized by CYP3A4 (drug interactions)

91% excreted in feces

88
Q

NS5A inhibitors (daclatasvir): drug interaction

A

metabolized by CYP3A4 - CAUTION WITH AMIODARONE - SEVERE BRADYCARDIA

89
Q

NS5A inhibitor (daclatasvir): MOA and use

A

Hep C

inhibit NS5A, a protein required for HCV RNA replication and assembly

90
Q

NS5B inhibitor (NPI): adverse effects

A

adverse effects as a result of combo therapy

  • nausea
  • HA
  • anemia
  • insomnia
91
Q

NS5B inhibitor (NPI): drug interaction

A

amiodarone - severe bradycardia

92
Q

Nucleoside reverse transcriptase inhibitors (NRTIs): adverse effects

A
  • Nausea
  • diarrhea
  • myalgia
  • increased LFTs
  • peripheral neuropathy
  • renal toxicity
  • marrow suppression
  • anemia
  • lactic acidosis
93
Q

NRTIs: drug interaction

A

VERY POWERFUL INHIBITION OF CYP450

-zidovudine + corticosteroids can = severe myopathy including resp muscle dysfunction

94
Q

Protease Inhibitors (PI), ritonavir: adverse effects

A
  • hyperlipidemia
  • glucose tolerance
  • abnormal fat distribution
  • altered LFTs
  • inhibition of cyp 450 3A4
95
Q

Protease inhibitors: drug interactions

A

INHIBITION OF CYP 3A4

–decreased fentanyl clearance ~67% (lower dose)

96
Q

Nonnucleoside analog reverse transcriptase inhibitors (delavirdine AND nevirapine): drug interactions

A

Delavirdine - INHIBITS CYP 450

    • inc concentrations of:
  • —sedatives
  • —antiarrhythmics
  • —warfarin
  • —calcium channel blockers

Nevirapine - induces CYP 450 by 98%!!

97
Q

Integrase strand transfer inhibitors (ISTIs): effects

A

appear well tolerated
new agents
may have unknown SE

98
Q

chemokine receptor 5 antagonists and entry inhibitors: effects

A

appear well tolerated
newer
may have unknown SE

99
Q

chemokine receptor 5 antagonists and entry inhibitors: drug interactions

A

appears to interact with midazolam altering clearance and drug effect

100
Q

Ritonavir (protease inhibitor): interactions with midaz

A

increased effects, lower dose

101
Q

Ritonavir (protease inhibitor): interactions with fentanyl

A

increased effects, lower dose

102
Q

Ritonavir (protease inhibitor): drugs to avoid

A

PRONOUNCED EFFECTS: LIFE THREATENING

  • meperidine
  • amiodarone (arrhythmias)
  • diazepam
103
Q

Parturient and antimicrobials: considerations

A

-most antimicrobials cross the placenta and enter maternal milk

-plasma concentrations could be 10-50% lower than predicted
–increased maternal blood volume, GFR, metabolism
(MAY NEED TO INCREASE DOSE, MAY BE METABOLIZED AND CLEARED FASTER)

-teratogenicity

104
Q

Elderly and antimicrobials: considerations

A
  • renal impairment
  • decreased plasma protein
  • reduced gastric motility and acidity
  • –altered distribution: increased total body fat
  • –decreased plasma albumin concentration
  • –decreased hepatic blood flow
  • –decreased GFR
105
Q

Pregnancy and antimicrobials: SAFE

A
  • penicillins
  • cephalosporins
  • erythromycin
106
Q

Pregnancy and antimicrobials: CAUTIOUS

A

-aminoglycosides (ototoxicity in mom and baby)

107
Q

Pregnancy and antimicrobials: CONTRAINDICATED

A
  • flagyl
  • tetracyclines
  • fluoroquinolones
  • trimethoprim
108
Q

Elderly and antimicrobials: SAFE

A

safe if normal serum creatinine concentration

  • penicillins
  • cephalosporins
109
Q

Elderly and antimicrobials: CAUTION

A

aminoglycosides and vancomycin may require adjustments in dose