MIC 541-Exam 4- Antimicrobials III - 2

  1. Define Cmax:
    The peak plasma concentration of a drug after administration
  2. What parameter of defines the total drug exposure?
    AUC = area under serum concentration time curve
  3. AUC is the time period when:
    the concentration in the patient is above the MIC
  4. What type of growth would be indicated for an anti-metabolite?
    The growth would increase and then plateau at a lower rate than normal
  5. Pharmacokinetic parameters quantify what?
    the serum level time course of an antibiotic
  6. Cmax, Cmin and AUC are all used for what?
    To quantify the serum level time course
  7. Cmax, Cmin and AUC were discussed in class as not able to quantify what parameters alone?
    Do not quantify the killing activity
  8. Comparing the Plasma level time curve components (e.g. AUC and Cmax) to what other parameter gives us pharmacodynamic efficacy and killing power of the drug?
  9. Cmax:MIC is important to what type drugs?
    Conc. dependant drugs
  10. What three pharmacodynamic properties can be used to determine killing properties of a drug?
    • Cmax:MIC
    • AUC:MIC
    • Time above MIC
  11. Cmax:MIC, AUD:MIC and time above MIC are pharmacodynamic properties that describe killing in terms of what?
    • Time dependence
    • persistent effects
    • concentration dependence
  12. Cmax:MIC, AUC:MIC and time above MIC are the same for most drugs (T/F)?
    False, different for each drug
  13. Rate of killing is determined by what pharmacodynamic factors?
    Time above the MIC or the effect of increasing the concentration
  14. Persistent pharmacodynamic effects include:
    the PAA, the persistent antimicrobial effects after the antimicrobial is removed
  15. What is the best predictor of killing power?
    • 24 hour area under teh curve to MIC ratio or the Peak concentration to MIC ratio
    • To prevent resistance what should the peak MIC ratio for Aminoglycosides be?
    • peak MIC ratio = at least 8-10 is best to prevent resistance
  16. What 24 hour AUC:MIC is optimal for flouroquinolones against gram negative bacteria?
    AUC:MIC =125
  17. What 24 hour AUC:MIC is optimal for flouroquinolones against gram + bacteria?
    AUC:MIC =40 optimally
  18. Optimal pharmacodynamic ratios are stable from study to study (T/F)?
    False, they vary from study to study
  19. What may account for differences across pharmacodynamic ratio studies?
    • Missed factors
    • Experimenetal error
  20. Pharmacodynamic ratios are very usefulin daily application of susceptibilty (T/F)?
    • False, there is too much variation in these ratios
    • Not yet reliable
    • Different inoculum in the lab than in the patient
  21. The critical determinant for the Pharmacodynamic ratios disscussed in class was: MIC =critical determinant
  22. What is teh standard inoculum for susceptibilty testing in the lab?
    • 5x 10^5
    • If increase inoculum concentration, what happens to the MIC?
    • The MIC dramatically increases
  23. The MIC dramatically increases when you alter what other parameter?
    The inoculum concentration
  24. What inoculum that is commonly found in the patient (as disscussed in class) is what?
    • 5x10^7
    • A change in inoculum from 5x10^5 to 5 x 10^7 could have an MIC change of what multiplier (as shown in the study)?
    • 100s of times higher
  25. The MIC in the lab is always the same as an MIC in the patient (T/F)?
    False, it can be drastically different
  26. The pharmacodynamic efficacy of which drugs is Cmax:MIC dependant?
    • Flouroquinolones
    • Aminoglycosides
  27. The pharmacodynamic efficacy of which general type of drugs is Cmax:MIC dependant?
    Concentration dependant drugs
  28. The pharmacodynamic efficay of what drugs is AUC:MIC dependant?
  29. The pharmacodynamc efficacy of which drugs is Time above MIC dependant?
  30. The pharmacodynamc efficacy of what general type of drugs is Time above MIC dependant?
    Concentration-independent drugs
Card Set
MIC 541-Exam 4- Antimicrobials III - 2
MIC 541-Exam 4- Antimicrobials III - 2