💊370: Antibiotics Flashcards

(73 cards)

1
Q

What are the shape classifications of bacteria?

A
  1. Bacillus/bacilli - Rod shaped
  2. Coccus/cocci - Spherical
  3. Spirilla - Spiral
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Bactericidal

A

Kill organism by cell lysis

For infection at sites of poor penetration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Bacteriostatic

A

Inhibit bacterial replication

Rely on host immune system (thus not immunocompromised)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Speciation

A

Identify bacterial species

Biochemical tests, PCR, etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Culture and Sensitivity (C&S) Testing

A

Sensitive (S)
Intermediate (I)
Resistant (R)

To each antibiotic tested

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which sites do antibiotics generally have poor penetration to?

A
  1. Brain
  2. Bone
  3. Heart
  4. Abscesses - require surgical drainage

Need ⬆️ doses to sites of poor penetration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which antibiotics should be avoided in pregnancy as they cross the placenta?

A
  1. Fluoroquinones
  2. Metronidazole
  3. Septra (Trimethoprim)
  4. Tetracyclines

(For Mother’s Safe-T Treatment)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the different effects of combination therapy?

A
  1. Additive response
  2. Synergistic response
  3. Antagonistic response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

When is antibiotic combination therapy used?

A
  1. Severe infection
  2. Multiple infections
  3. Resistance prevention
  4. Decreasing toxicity (dec doses)
  5. Synergistic activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are factors to consider during antibiotic dosing?

A
  1. Weight
  2. Site of infection
  3. Route of elimination
  4. Time- vs concentration-dependent killing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the Minimum Inhibitory Concentration (MIC)?

A

Lowest concentration of antibiotic required to inhibit visible bacterial growth in vitro

Lower MIC = more effective antibiotic against that organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Time-dependent killing Antibiotics

A

Determined length of time drug remains above MIC

Ex. Penicillins, cephalosporins, erythromycin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Concentration-dependent killing Antibiotics

A

Rate and extent of killing improved with high peak drug concentration

Ex. Aminoglycosides, fluoroquinolones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Renal Dose Adjustment

A

Required for agents with high renal elimination

Time-dependent killing = ⬇️ dose

Concentration-dependent killing = ⬆️ interval

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What factors help determine when to stop antibiotic treatment?

A
  1. Host defenses
  2. Site of infection
  3. Infecting pathogen
  4. Negative cultures
  5. Patient response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Patient assessment and monitoring on antibiotic treatments?

A
  1. Leukocytes (⬆️WBC, ⬆️neutrophils)
  2. Metabolism (⬇️ nitrogen, Mg2+, K+, PO4-)
  3. CV effects (⬆️HR, ⬆️RR, ⬇️BP)
  4. Renal effects (Proteinuria, dehydration, ⬇️ renal perfusion, ⬇️urine output)
  5. Site-specific symptoms (UTI, pneumonia, meningitis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When should a nurse be concerned while evaluating antibiotic efficacy?

A
  1. Fever unresolved after 3 days
  2. Signs and symptoms increased/unresolved
  3. Continued symptoms after course of therapy complete
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are common indications for antibiotic prophylaxis?

A
  1. Surgical procedures
  2. Bacterial endocarditis
  3. Neutropenia
  4. Other (recurrent UTI, HIV+, transplant, immunosuppression)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are examples of resistant strains (“superbugs”)?

A
  1. Enterococcus (VRE)
  2. Staphylococcus aureus (MRSA)
  3. Escherichia coli
  4. Pseudomonas aeruginosa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the leading cause of antibiotic resistance?

A

Misuse and overuse of antibiotics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How do bacteria become resistant?

A

Adaptive changes:

  1. Drug metabolizing enzymes
  2. Decreased uptake of drugs
  3. Microbial drug receptors
  4. Synthesis of compounds that antagonize drug action
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the mechanism of action of Beta-Lactam Antibiotics?

A

Inhibit bacterial cell wall synthesis
(Bactericidal)

Target penicillin-binding protein (PBP) on cell cytoplasmic membrane (basis of selectivity)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are drug classes of Beta-Lactam antibiotics?

A
  1. Penicillins
  2. Cephalosporins
  3. Carbapenems
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are types of penicillins?

A
  1. Natural penicillins (narrow spectrum)
  2. Penicillinase-resistant penicillins
  3. Aminopenicillins
  4. Extended-spectrum penicillins
  5. Penicillins + beta-lactamase inhibitor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Why does penicillin resistance arise?
Penicillinase | Gram negative cell envelope
26
What are natural penicillins?
Penicillin G = IV form Penicillin V = oral form Narrow spectrum Sensitive gram positive cocci
27
What is the mechanism of action of bacteria resistance to penicillin?
Bacteria produce enzyme beta-lactamase (penicillinase) that cleaves the Beta-lactam ring to inactivate penicillin
28
What is a prototype of penicillinase-resistant penicillins?
Cloxacillin Only agent effective against staphylococcus Not effective against MRSA
29
What are the main agents of aminopenicillins?
Ampicillin (IV/PO) Amoxicillin (PO) Broader spectrum Penetrate gram negative cell envelope
30
What are common therapeutic uses for aminopenicillins?
UTI Respiratory tract infection Otitis media
31
What is the main agent of antipseudomonal penicillins?
Piperacillin (IV) Broad spectrum (penetrated gram negative cell envelope) Active against pseudomonas
32
What are common therapeutic uses for antipseudomonal penicillins?
Serious infections (ie sepsis) due to Pseudomonas
33
What is the use for penicillins + Beta-Lactamase inhibitors?
Broadens spectrum of activity Amoxicillin + clauvinic Acid (Clavulin) (PO) Piperacillin + tazobactam (Tazocin)(IV)
34
Cephalosporins
1. More resistant to beta-lactamases 2. ⬆️ gram negative, ⬇️ gram positive 3. ⬆️ CSF penetration 4 generations in Canada
35
What are examples and common therapeutic uses of First generation cephalosporins?
Cefazolin IV, cephalexin PO 1. Skin and soft tissue infections 2. Surgical site infection prophylaxis
36
What are examples and common therapeutic uses of Second generation cephalosporins?
Cefaclor PO, cefuroxime PO/IV Respiratory tract infections
37
What are examples and common therapeutic uses of Third and Fourth generation cephalosporins?
3rd: ceftriaxone, ceftazidime 4th: cefepime IV Severe infections (meningitis, febrile neutropenia) **3rd gen can lead to C-diff
38
What are examples and therapeutic uses of Carbapenems?
Ex. Imipenem, meropenem Broadest spectrum agents Resistant to penicillinases Parenteral forms ONLY
39
What are side effects of Beta-Lactams?
GI: n/v, diarrhea Neuro: seizures (penicillins; impenem at high IV doses) Dermatologic: thrombophlebitis (minimize by diluting dilution and slowing infusión time) Allergic reactions
40
Antibiotic allergy
Symptoms: itching, rash, face swelling, urticaria, flushing, dizziness, syncope, wheezing, throat tightness, trouble breathing Management: antihistamines, corticosteroids, epinephrine
41
What are the pharmakinetics and drug interactions of Beta-Lactams?
Short half-lives Better absorption on empty stomach (ex. Cloxacillin)
42
What is the mechanism of action of Vancomycin?
Inhibits cell wall synthesis (bactericidal) Large molecule, not orally absorbed
43
What are common therapeutic uses for Vancomycin?
1. MRSA 2. Serious infections in penicillin-allergic pts 3. C. difficile (only orally)
44
Which antibiotic induces Red Man Syndrome?
Vancomycin
45
What is Red Man Syndrome?
Histamine-mediated reaction - flushing of trunk, neck and face - hypotension Management: slow infusion rate, antihistamines
46
What are side effects of Vancomycin?
1. Red Man Syndrome | 2. Nephrotoxicity (avoid high trough levels)
47
What are dosing and administration requirements of Vancomycin?
IV and PO forms Renal dose adjustment required (IV only)
48
What is a prototype of aminoglycosides?
Tobramycin
49
What is the mechanism of action of aminoglycosides?
Disrupt bacterial protein synthesis (bactericidal) Large, positively charged molecules Not orally absorbed
50
What are common therapeutic uses of aminoglycosides?
1. Serious gram negative infections (ex. Pseudomonas) 2. Gram positive infections (combined with bets-lactam) 3. Ophthalmic/optic infections (eye or ear drops)
51
What are drug interactions with aminoglycosides?
1. Aminoglycosides + beata-lactams or Vancomycin can increase effectiveness BUT can’t be mixed in IV bag d/t chemical rxn 2. Nephrotoxic drugs increase renal damage (ex. Vancomycin, NSAIDs)
52
What are side effects of aminoglycosides?
1. Nephrotoxicity (unreversible) 2. Ototoxicity (tinnitus, headache, vertigo) 3. Parasthesias, seizures Increased risk if high trough levels and prolonged duration
53
What is the dosing and administration of aminoglycosides?
Higher peak = more effective (concentration-dependent killing) Post-antibiotic effect = washout period = safer Renal dose adjustment required PARENTAL, eye/ear drops
54
What are types of macrolides?
Erythro- Clarithro- Azithromycin
55
What is the mechanism of action for macrolides?
Inhibit bacterial protein synthesis (bacteriostatic)
56
What are common therapeutic uses for macrolides?
1. Respiratory tract infections (ex. Pneumonia) 2. Chlamydia, diphtheria 3. Alternative to penicillin-allergic pts
57
What are side effects of Macrolides?
1. GI: n/v, diarrhea 2. Erythro- and clarithro- inhibit CYP450 enzymes 3. Azithro- do not take with Aluminum, Mg2+, Ca2+ 4. Antagonize effects of clindamycin
58
What are therapeutic uses for Flourquinolones?
1. UTIs 2. Pneumonia 3. Infection of bones/joints/soft tissue 4. Gut infection (travellers diarrhea) 5. Opth/optic infections
59
What are specific drug interactions with Flourquinolones?
Bioavailability decreases with Dairy, antacids, minerals (Ca/Mg/Iron)
60
What are side effects of Flourquinolones?
1. N/v, diarrhea 2. Headache, dizziness 3. Peripheral neuropathy 4. MSK pain 5. Tendinitis, tendon rupture 6. Cartilage growth suppression **could lead to c.diff
61
What is a prototype of Flourquinolones?
Ciprofloxin “-floxin” (IV, PO, ear/eye drops)
62
What is a prototype of Metronidazoles?
Flagyl | PO, IV
63
What are common therapeutic uses for Metronidazoles?
1. C. difficile 2. Anaerobic infections of CNS/abdomen/bone/joint/soft tissue/pelvis 3. Surgical prophylaxis 4. Protazoal infections (the tail- Flagyl!)
64
What are common side effects of Metronidazoles?
1. N/v, diarrhea 2. Metallic taste 3. Dizziness, vertigo 4. Brown urine
65
What are specific drug interactions with Metronidazoles?
ALCOHOL Inhibits aldehyde dehydrogenase, leads to build up of acetaldehyde - headache, n/v, flushing, SOB
66
What is the mechanism of action for Sulfonamides?
Disrupt folate synthesis do bacteria cannot make DNA/RNA/proteins
67
What are 2 prototypes of Sulfonamides?
1. Sulfamethoxazole 2. Trimethoprim (Septra) (PO, IV)
68
What are therapeutic uses for Sulfonamides?
1. UTIs | 2. PCP (pneumocystis carnii pneumonia, AKA Pneumoncystis jiroveci)
69
What are specific drug interactions with Sulfonamides?
Highly protein bound - displace other drugs (Warfarin, phenytoin, Sulfonylureas) **Sulfa allergy
70
What are side effects of Sulfonamides?
1. Hypertensitivity rxn (mild rash fever, photosensitivity) 2. Low WBC/platelets 3. Hemolytic anemia (rare) 4. N/v, diarrhea 5. STEVENS-JOHNSON Syndrome
71
What is the mechanism of action for Clindamycins?
Inhibit bacterial protein synthesis BACTERIOSTATIC
72
What are therapeutic uses for Clindamycins?
1. Mixed infections 2. Skin/soft tissue 3. Aspiration pneumonia 4. Abdominal/pelvic infections 5. Alternative to penicillin
73
What are common side effects of Clindamycins?
DIARRHEA (lead to C.diff)