Antimicrobial therapy 1 and 2 AND Antimicrobial therapy reading Flashcards

(159 cards)

1
Q

When are ABs most effective?

A

When they supplement the body’s natural defences rather than being used alone

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2
Q

What is the most important resistance code?

A

R plasmids (may involve genes that impart resistance to unrelated ABs)

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3
Q

What may impair the effectiveness of antimicrobial therapy? 3

A

urinary calculi, FB or need for surgical drainage

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4
Q

How would the mechanism of bacterial killing affect the type of drug?

A

Concentration versus time-dependent actions

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5
Q

Why are more selective drugs preferred?

A

less likely to disrupt the normal flora

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6
Q

What should be considered when choosing whether to use a bacteriostatic or bacteriocidal drug?

A

Bactericidal drugs are often favoured because they may be more effective when host defences are impaired. However, there may be little difference in efficacy between bactericidal and bacteriostatic drugs when treating non‐critical infections in otherwise healthy patients.

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7
Q

To which organ is gentamicin toxic?

A

nephrotoxicity

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8
Q

Which breed of dog can’t be given sulphonamides?

A

Dobermans

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9
Q

What organ system is affected by erythromycin?

A

GIT

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10
Q

Name 5 bacteriostatic drugs

A

tetracyclines, chloramphenicol, non‐potentiated sulphonamides, macrolides and lincosamides

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11
Q

How and when do bacteriostatic drugs work?

A

temporarily inhibit the growth of an organism but the effect is reversible once the drug is removed. For these drugs to be clinically effective the drug concentration at the site of the infection should be maintained above the MIC throughout the dosing interval. As a result, adherence to correct dose timing is important and clients should be instructed to administer drugs every 24, 12 or 8 hours rather than once, twice or three times daily.

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12
Q

List 6 bacteriocidal drugs

A

aminoglycosides, cephalosporins, fluoroquinolones, metronidazole, penicillins, potentiated sulphonamides

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13
Q

When to use bacteriocidal drugs

A
  • depends on nature or site of infection

- reduced immunocompetence of host

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14
Q

How are bacteriocidal drugs further classified?

A

time or concentration dependent

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15
Q

List time-dependent bacteriocidal drugs 3

A

penicillins, cephalosporins, TMPS

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16
Q

Why shouldn’t time dependent bacteriocidal drugs be given with bacteriostatic drugs?

A

bacteria need to be multiplying for bacteriocidal drugs to be effective

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17
Q

How high a dose of bacteriocidal drugs should be given?

A

above MIC for 80% of 24 hours to reduce risk of resistance emerging

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18
Q

Is there any benefit achieivng a Cmax 2-4 times the MIC for bactericidal drugs?

A

no

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19
Q

List 3 concentration dependent bacteriocides

A

aminoglycosides
fluorquinolones
metronidazole

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20
Q

What determines antibacterial success with concentration dependent bactericides (aminoglycosides, fluoroquinolones and metronidazole)

A

all 3 - peak concentration

fluoroquinolones - area under the plasma concentration/time curve

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21
Q

Common bacterial cause of UTIs

A

E.coli

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22
Q

Common cause of skin infectins

A

Staphylococcus spp

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23
Q

Which group of bacteria are you likely to find in pyothorax and abscesses?

A

obligate and facultative anaerobes

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24
Q

Where might bacteria come from in supparative cholangiohepatitis?

A

GIT contents - gram negative plus anaerobes

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25
What are the atypical bacterial spp which don't gram stain?
rickettsia, mycoplasma, chlamydia, borrelia, bartonella, mycobacterium
26
What is the most practical classification of bacteria in small animal practice? 5
- gram positive aerobic (and facultative anaerobes) - gram negative aeorobic (and facultative anaerobes) - obligate anaerobes (gram negative and positive) - penicillinase-producing staphylococcus - atypical bacterial spp
27
Define pharmacokinetic phase
distribution to the site of infection
28
What affects pharmacokinetics?
if tissue has adequate blood supply, antibac concentrations in serum/plasma being equal to extracellular (interstitial) space unless highly protein bound (uncommon), diffusion to certain areas limited, poorly vascularised tissues
29
What are some consequences of poor AB compliance by owner?
inadequate response to treatment, risk of resistance, increased risk of recurrent infetions, abrupt discontinuation may cause side effects (some drugs), risk of toxicity (if owner tries to catch up on missed doses), increased costs, creation of doubt in clients mind about efficacy (drug/clinician), accumulation of unused meds in home.
30
What is perioperative infection risk influenced by?
``` Clinical status of patient Nature of surgery Use of implants Experience of surgeon Duration of surgery Total duration of anaesthesia Administering propofol Clipping Animals with high/low BCS Animals with concurrent endocrinopathies ```
31
How does duration of surgery affect infection risk?
1.5 hours infection rate is 8%
32
How does total duration of anaesthesia affect infection risk?
For every minute beyond 60 minutes, there is a 0.5% increase in risk
33
How does propfol affect infection risk?
Animals receving propofol 3.8 times more at risk than those that don't
34
How does clipping affect infection risk?
Surgical sites clipped before anaesthetic induction are 3 times more likely to develop post-op infection. Especially in animals >8years
35
When is prophylactic AB treatment indicated?
- after dentals (controversial) - leucopaenia (viral or drug induced) - contaminatd surgery - surgeyr where consequences are disastrous (orthopaedic) - major tissue trauma (major thoracic and abdominal surgery) - surgery time >90 mins
36
When should prophylactic ABs be given?
Before procedure so adequate levels are in blood at time of surgery to achieve max. effect.
37
When is prophylactic AB advantages lost?
if commenced any later than 3-5 hours after contamination. IV administration 20-30 mins prior to surgery is recommended
38
For how long post-op is therapy usually given?
not usually continued longer than 24 hours post-op
39
What are the most frequent veterinary nosocomial infections? 4
Klebsiella spp E. coli Proteus Pseudomonas
40
Which ABs have the greatest potential to suppress endogenous flora that normally keep pathogenic enteric bacteria in check? Give 3 examples of each.
- If they have extensive activity against obligate anaerobes (penicillins, chlorampnehicol, lincosamides) - if they undergo extensive entero-hepatic recycling (TCs, chloramphenicol, lincosamides)
41
Which ABs don't tend to suppress endogenous flora? 4
- Cephalosporins - aminoglycosides (PN) - TMPS - sulphonamides
42
What are the 'points' of the therapeutic triangle?
host, drug, bacterium
43
Having established there is a bacterial infection, what questions should be asked? 4
- which drugs have a suitable spectrum of activity? - i sthe mode of action suitable for the status of the patient? - will the drug reach the site of infection t adequate concentrations? - will the drug harm the patient?
44
Name the 2 beta-lactam ABs
penicillins and cephalosporins
45
How do beta-lactam ABs kill?
inhibition of cross-linking of peptidoglycan molecule in cell wall. time-dependent. activation of autolysins is though to lead ot breakdown of peptidoglycans
46
Describe spectrum, pharmacokinetics and toxicity of penicillins and cephalosporins
Spectrum of activity o highly variable between sub‐families o can vary within a family (good vs. anaerobes) • Pharmacokinetics o all organic acids, charged at physiological pH o most are renally excreted and concentrated in urine • Toxicity o wide therapeutic indices in general
47
What are the penicillin sub-families? 5
``` natural (penicillin G an V) isoxazoylpenicillins aminopenicillins carboxypenicillins ureidopenicillins ```
48
Spectrum of natural penicillins
narrow spectrum, beta‐lactamase | susceptible
49
Spectrum of isoxazoylpenicillins
narrow spectrum, resistant to | beta‐lactamase of staphylococci
50
Spectrum of aminopenicillins
broad spectrum but susceptible to beta‐lactamase unless coformulated with clavulanic acid
51
Spectrum of carboxypenicillins
effective vs. difficult G‐ve organisms such as | P.aeruginosa (but susceptible to beta‐lactamases)
52
Spectrum of ureidopenicllins
broader spectrum than the carboxypenicillins ‐ | effective vs. Klebsiella and Bacteroides fragilis
53
When should you use clavulanate potentiated ticarcillin?
reserved for difficult life‐threatening G‐ve infections
54
Which generation of cephalosporin has broadest spectrum?
second generation cephalosporins generally have broadest spectrum of activity, retaining good G+ve activity (including vs. Staphylococci), good anaerobic activity and reasonable G‐ve activity. These drugs are used in human medicine for surgical prophylaxis
55
What do third generation cephalosporins target?
developed particularly to extend the spectrum of these drugs to include Pseudomonas and Klebsiella. They have lost some activity against the G+ve organisms and should be reserved for difficult G‐ve infections.
56
What is cefovecin?
A new cephalosporin – cefovecin – was launched in 2007 for small animal use. It is classed as a third generation drug but its spectrum does not include Pseudomonas and Klebsiella spp. Its unique characteristics are that it has a very prolong duration of action with a single dose providing 10 to 14 days of antibiotic cover due to a prolonged plasma clearance.
57
Which ribosomes do TCs work against?
both pro- and eukaryotic ribosomes
58
How are TCs selectively toxic?
ability of bacteria and other micro‐organisms to concentrate these drugs within their cells, a property which mammalian cells lack. Equally, this means that resistance to tetracyclines is achieved by loss of the transport protein from the micro‐organism.
59
How are TCs divided?
water soluble and lipid soluble types Water soluble = chlor- and oxy- Lipid soluble = mino- and doxy-
60
Water soluble TCs - spectrum of activity?
Spectrum of activity o broad spectrum antimicrobial drugs, including Chlamydiae, Rickettsiae and Mycoplasma o limited by resistance
61
Water soluble TCs - pharmacokinetics?
oral bioavailability affected by food (milk) – especially the water soluble compounds o distribute widely; especially lipid soluble drugs o renal and biliary excretion (re‐circulates)
62
Water soluble TCs - toxicity?
avoid in renal failure as renally excreted, mildly nephrotoxic (degradation product of drug), more likely to cause liver damage if given to animals with renal failure at standard doses. In addition, the anti‐anabolic effects of these drugs may worsen the azotaemia o intravenous administration can cause circulatory collapses because chelate calcium
63
What are the features of lipid soluble TCs?
more lipid soluble than other tetracyclines o penetrate the prostrate gland o penetrate the blood bronchus barrier • doxycycline eliminated in faeces so safer in renal failure • doxycycline is marketed for respiratory infections
64
How are aminoglycosides bactericidal?
cause a mis-reading of mRNA allowing nonsense proteins to be produced
65
What are current thoughts on the ways of increasing efficacy and lowering toxicity of aminoglycosides?
pulse-dosing
66
What is the spectrum of activity of aminoglycosides?
varies within the family of drugs o noted for their G‐ve aerobic antibacterial actions o they do have good actions against Staphylococci but generally have poor action against other G+ve cocci o inactive against obligate anaerobes and facultative anaerobes growing under anaerobic conditions (need oxygen to enter cells).
67
What are the pharmacokinetics of aminoglycosides?
weak bases, highly hydrophilic | o do not cross cellular barriers, low volume of distribution
68
What sort of toxicity are aminoglycosides noted for?
noted for their nephrotoxicity and otoxicity o skeletal neuromuscular junction blockade can occur, particularly in anaesthetised patients
69
What are amikacin and tobramycin?
newer aminoglycosides, licensed for human use
70
What is known about amikacin?
less active than gentamicin but resistant to many of the inactivating enzymes produced by bacteria so may be effective for bacterial infections which are resistant to gentamicin
71
What is known about tobramycin?
more active than gentamicin vs. Pseudomonas aeruginosa | o reduced nephrotoxicity
72
Why are macrolides and lincosamides grouped?
These are two families of antimicrobial drugs which have similar spectra of activity and pharmacokinetic properties. Both groups are bacteriostatic and work by inhibiting protein synthesis.
73
What is the spectrum of activity of macrolides /lincosamides?
``` narrow spectrum (G+ves mainly); effective vs. Staphylococci particularly o active vs. anaerobes (especially Clindamycin) and Mycoplasma ```
74
Pharmacokinetics - macrolides / lincosamides?
lipophilic weak bases, distribute widely o ion‐trapped in acidic fluids‐ milk, prostatic, intracellular o eliminated by hepatic metabolism
75
Toxicity - macrolides / lincosamides?
Safe drugs o Erythromycin ‐ causes vomiting consistently in dogs o Interactions with other drugs (e.g., terfenadine) well recognised in human medicine (led to terfenadine being removed as an over‐the‐counter antihistamine)
76
What is spiramycin?
- a macrolide combination with metronidazole o synergistic combination for anaerobes in mouth, produced for the managements of gingivitis o remarkable tissue binding capacity
77
What are azithromycin and clarithromycin?
- new macrolide - similar spectrum activity to erythromycin o more potent and longer half lives than erythromycin in people o more work is required in veterinary medicine but these drugs may be more convenient in terms of having to dose less frequently in the dog and cat
78
What sort of action do potentiated sulphonamides have?
Either drug alone is bacteriostatic but together they produce a bactericidal effect and are synergistic in their actions
79
Which spp can you use trimethoprim in?
Trimethoprim was developed for human use and is not appropriate for systemic infections for many veterinary species since its half life is very short and does not match the sulphonamide with which it is combined.
80
Spectrum of activity - potentiated sulphonamides
- broad spectrum antimicrobials (not difficult G‐ves or serious anaerobic infections) o synergism occurs even if the organisms is resistant to sulphas
81
Pharmacokinetics - potentiated sulphonamides
``` widely distributed (weak acid ‐ sulphas; weak bases ‐ diaminopyrimidines) o ideally, would like the combination to have matched pharmacokinetics ```
82
Toxicity - potentiated sulphonamides
idiosyncratic immune‐mediated reactions (many), particularly in Dobermann Pinschers but many breeds are affected o Crystalluria, particularly occurs in concentrated acidic urine
83
How have fluoroquinolones been developed?
structural modifications made to nalidixic acid to | improve the spectrum of activity and reduce the toxicity.
84
How do fluoroquinolones affect bacteria?
They are bactericidal and kill by a concentration dependent mechanism having a marked post‐antibiotic effect (PAE). They inhibit the bacterial enzyme, DNA gyrase and so prevent super‐coiling of bacterial DNA.
85
Spectrum of activity - fluoroquinolones
broad spectrum (includes Mycoplasma, Rickettsiae) but not anaerobes, Streptococci or enterococci. o minimum inhibitory concentration is very close to the minimum bactericidal concentration
86
Pharmacokinetics - fluoroquinolones
- widely distributed, orally active | o crosses BBB, penetrate into cells (highly concentrated within cells)
87
Toxicity - fluoroquinolones - 4
- use with care in epileptics o erosion of articular cartilage in growing dogs o can alter the kinetics of other drugs (e.g., methylxanthines; digoxin) o retinal blindness in cats if flexible dosing regimens adopted
88
Use of fluoroquinolones
- probably shouldn't use as first line antibacterial drugs • reserve for difficult G‐ve infections which are resistant to first line drugs • use in septicaemic patients with an appropriate beta‐lactam • use for recurrent UTI and chronic bacterial prostatitis
89
Spectrum of activity - chloramphenicol
- broad spectrum, including anaerobes, G+ve and G‐ve | bacteria (not Pseudomonas spp), chlamydia, rickettsiae (but plasmid mediated resistance occurs)
90
Pharmacokinetics - chloramphenicol
excellent tissue penetration (small uncharged lipophilic molecule)
91
Toxicity - chloramphenicol - 2
o bone marrow toxicity (particularly cats ‐ reversible) | o hepatic enzyme inhibition (irreversible; particularly affects barbiturate metabolism)
92
What are florfenicol and thiamphenicol?
structural analogues of chloramphenicol which have been marketed for veterinary use in Europe.
93
Why were florfenicol and thiamphenicol produced?
to try and overcome problems of aplastic anaemia in man but not currently licensed for small animals (developed for calves)
94
How do ABs lead to resistance?
their use preferentially selects resistant populations of bacteria.
95
When to use antimicrobials? 4
- definitive diagnosis - likely diagnosis - likely to progress without medical therapy - would cause critical illness
96
What is empirical therapy?
making an educated guess as to the cause of the illness and therefore which AB to prescribe
97
When is culture and sensitivity recommended?
if therapy fails or immediately recurs once therapy has ceased.
98
What clues would suggest that bacterial infection may cause critical illness?
- heat, redness and/or swelling - pyrexia - neutrophilia -
99
Is vomiting without diarrhoea likely to have a bacterial cause?
No - the only bacteria causing upper GIT disease is Helicobacter and this is very rare (extensive therapy required in these cases)
100
Is haematuria in cats <10 years old likely to be caused by bacteria?
No (in dogs yes the most common cause of UTI is bacterial). In cats, their urine is highly concentrated and bactericidal so unlikely. Approx 2 % cats presenting with signs of UTI have bacterial infection. Feline idiopathic cystitis (probably stress is a driver) most likely - these cases are often put on antimicrobials (5-7d) after which they get better but this is nothing to do with the drugs!
101
Is blood in faeces likely to have a bacterial aetiology?
No - only give ABs if systemic signs present.
102
What should you consider when deciding whether to give ABs? 7
- predict likely bacteria involved? - predict likely susceptibility? - culture needed/feasible? - pharmacokinetic factors? - potential side effects and increased risk for your patient? - any client compliance issues? - cost consdierations?
103
5 factors affecting success of AB therapy
- what bugs live where? - bacterial susceptibility - pharmacokinetic phase - pharmacodynamic phase - client compliance
104
Where do infections come from?
ENVIRONMENT - myocbacteria, tetanus, contaminated food (Campylobacter and E. coli) OTHER ANIMALS - Bordatella FROM WITHING - GIT, skin
105
Generally what does it mean if a bacteria is not susceptible to a drug in vitro? How can this be overcome?
they will be resistant in vivo - resistance may be overcome by high concentrations in urine or topical application.
106
What does it mean if a pathogen is sensitive to a drug in vitro?
The drug MAY be effective in vivo (depends on variety of pharmacological, host and bacterial factors).
107
Define MIC
minimum inhibitory concentration - lowest concentration of drug that will inhibit bacterial growth.
108
What is MIC90?
usual measure to determine therapeutic dose - concentration that will inhibit 90% isolates of a bacterial species.
109
What AM classes inhibit cell wall synthesis? 3
penicillins, cephalosporins and bacitracin
110
Which AM classes inhibit cell membrane function? 4
polymixins, amphotericin B, imidazoles, nystatin
111
Which AM classes inhibit protein synthesis? 5
chloramphenicol, macrolides/lincosamides, tetracyclines and aminoglycosides
112
Give an example of macrolides
eryhtromycin, tylosin
113
What is clindamycin?
A lincosamide
114
What are gentamicin and neomycin?
aminoglycosides (neomycin used especially in farm animal practice)
115
Which AM classes inhibit nucleic acid synthesis? 5
sulphonamides, trimethoprim, quinolones, metronidazole and rifampin
116
How are AMs classified as bacteriostatic or bacteriocidal?
Classification only really applies under strict lab conditions, inconsistent against all bacteria, becomes more arbitrary in clinical cases, more important to consider method of bacterial killing.
117
Describe the features of bacteriostatic action
Temporarily inhibit the growth of organisms, effect reversible once the drug is removed, to be clinically effective the drug concentration at the site of infection should be maintained above the MIC throughout the dosing interval (adherence to correct dosing schedule important).
118
True/False - many bacteriostatic drugs can be bactericidal if drug exposure is sufficiently high or prolonged.
True
119
list 5 bacteriostatic AB classes
- chloramphenicol - lincosamides - macrolides - tetracyclines - non potentiated sulphonamides
120
List 6 bactericidal AB classes
- penicillins - cephalosporins - aminoglycosdies - fluoroquinolones - potentiated sulphonamides (TMPS) - metronidazole
121
What 2 indications suggest use of bactericidal is better than bacteristatic?
when there is concern about site of infection or host defences
122
Which bactericidal drugs is dosing regime very important for? 3
penicillins, cephalosporins and TMPS. DON'T give thesewith bacteriostatic drugs.
123
For which ABs does peak concentration achieved or AUC predict therapeutic success? 3
aminoglycosides, fluoroquinolones, metronidazole (i.e. concentration dependent)
124
What is a red AB?
no useful activity against vast majority of bacteria in a qudrant
125
What is a green AB?
excellent activity against most bacterial spp in this quadrant
126
What is a blue AB?
good activity against many bacterial spp in this quadrant but some important spp are resistant
127
What is a brown AB?
has moderate activity against bacterial spp in a quadrant - some spp will be susceptible, others will be resistant
128
Name two AB classes that don't work against obligate anaerobes (gram negative and positive)
- fluoroquinolones (except pradofloxacin) | - aminoglycosides
129
Name 3 AB classes that don't work against penicillinase producing staph
- Penicillin G - Aminopenicillins - Metronidazole
130
In what kind of environment does Metronidazole work?
Anaerobic only
131
Name 3 AB classes that don't work against gram negative aerobes
- Metronidazole - Penicillin G - Lincosamides/ macrolides
132
Name 2 AB classes that don't work against gram positive aerobes
- aminoglycosides | - metronidazole
133
Name ABs that work against obligate anaerobes (gram negative and gram positive) - 6
- Penicillin G - Amoxy-clav - Clindamycin - metronidazole - chloramphenicol - rifampin
134
Name AB classes that work against penicillinase producing staph - 6
- amonxy-clav - 1st and 2nd generation cephalosporins (and cefovicin) - cloxacillin - fluoroquinolones - rifampin - clindamycin (blue, all above are green)
135
Name AB classes that work against gram negative aerobes - 5
- fluoroquinolones - aminoglycosides - 2nd and 3rd generation cephalosporins (not cefovicin) - ticarcillin-clavulanate - amoxy-clav (blue, all above are green)
136
Name AB classes that work against gram positive aerobes - 7
- Penicillin G - aminopenicillins - cephalosporins - lincosamides/ macrolides - tetracyclines - rifampin - fluoroquinolones (blue, all above are green)
137
What is a brown antibacterial?
If it doesn't appear in a quadrant as either red, green or blue, it means it has activity in that quadrant but there are a significant number of resistant bacterial species as well.
138
What are the brown drugs?
- 1st generation cephalosporins, cefovicin and amoxycillin (WITHOUT clavulanic acid) against gram negative aerobes and obligate anaerobes - lincosamides other than clindamycin against anaerobes - TMPS in all quadrants - tetracyclines in all quadrants except gram positive aerobes (but excellent activity against atypical bacteria)
139
Define distribution that is perfusion limited
Free drug concentration achieved in plasma are directly related to or equal to the concentration in the interstitial space
140
Define permeability limited
The level of drug distribution to some tissues. It means the lipid membrane is very tight and so forms a barrier to drug diffusion.
141
True/False - most antibacterial drugs reach therapeutically adequate concentrations in bone and synovial fluid
True
142
List sites in the body that are difficult to access for drugs - 7
- brain - eye - prostate (dogs) - bronchus - intracellular - poorly vascularised tissues (bone fragments or heart valves) - mammary gland (not in itself a problem but the blood-milk barrier is)
143
List 6 intracellular bacteria
- Bartonella - Brucella - Chlamydophila - Mycobacterium - Rickettsia - Staphylococcus - facultative
144
List 5 ABs that penetrate POORLY into cells (i.e. water soluble therefore difficult to cross into tissues)
- Penicillins - cephalosporins - beta lactamase inhibitors - polymixins - aminoglycosides
145
List 5 ABs that penetrate WELL into cells
- sulphonamides - trimethoprim - lincosamides - macrolides - tetracycline
146
List 5 ABs that penetrate EXCELLENTLY into cells (i.e. lipid soluble)
- chloramphenicol - fluoroquinolones - lipophilic tetracyclines (minocycline and doxycycline) - metronidazole - rifampin
147
What environmental conditions may hinder ABs from working?
- abscess formation - pus - necrotic debris - oedema fluid - foreign material
148
Why do foreign material affect AB?
Phagocytes degranulate to try to destroy the foreign material --> depleted intracellular bacterial substances --> relatively inefficient in killing bacterial pathogens. The foreign material can also protect bacteria from antibacterial drugs and prophylazis. Bacteria can form a biofilm (glycocalyx) at the site of infection
149
How does pus affect TMPS?
Pus inactivates TMPS
150
How does the presence of haemoglobin affect penicillin activity?
Penicillin activity is reduced
151
Low pH causes a marked loss of activity in which 3 AB drugs?
- erythromycin - clindamycin - fluoroquinolones
152
Name 4 factors affecting the post-op infection risk
- degree of contamination - organism virulence - patient health - local tissue health
153
When to use PERI-operative ABs?
Justification based on: - wound classification - disease process - patient health - presence of implants - consequences
154
At how much greater risk are animals that receive propofol of infection?
3.8 times
155
ABs can NOT compensate for what? 4
- gross contamination - local tissue trauma - compromised patient health - poor aseptic technique
156
What is the most useless drug to use for surgical prophylaxis in most small animal cases?
Amoxicillin because not effective against the most common infections in small animals. An even worse drug is a long acting version of this (e.g. farm animal formulation of amoxicillin takes 12 hours to reach therapeutic concentrations)
157
What type of AB drug would you use for surgical prophylaxis?
For routine surgery, the AB doesn't need to be green in all 4 quadrants
158
What are the best drugs for surgical prophylaxis? How to administer?
Influenced by type of surgery but common recommendations are: - 2nd generation cephalosporin (e.g. cefuroxamie) - amoxycillin-clavulanate - 1st generation cephalosporin Give I/V at time of induction if possible. Or SC or IM at least 1-2 hours prior to surgery.
159
Is the traditional 5 day post-op course of ABs appropriate for prophylatic ABs?
No