Rational Use of Antimicrobials Flashcards
When is it appropriate to use antimicrobials?
Definitive bacterial diagnosis, likely diagnosis of bacterial from c.s. and data, likely to progress without therapy, or would cause critical illness if not treated
When is it not appropriate to use antimicrobials?
In every problem, when you have nothing else, if therapy fails DO CULTURE
In which 3 situations is it extremely unlikely to have a bacterial cause?
1) Vomiting without diarrhoea, 2) Haemturia in cat <10 years, 3) Blood in faeces
What is the MIC? What is MIC90?
Minimum inhibitory concentration - lowest conc of drug that inhibits bacterial growth. MIC90 is usual measure used to determine therapeutic dose.
If a drug is a time dependent drug, what does this mean?
The time over the MIC over a 24 hour period predicts therapeutic success. Dosing needs to be accurate.
If a drug is concentration dependent, what does this mean?
Peak concentration of drug dictates therapeutic success.
What is a bacteriostatic drug? What is important with these drugs?
Drugs that temporarily inhibit growth of organisms, reversible if drug removed. Drug MIC should be maintained at infection site for dosing interval - CORRECT DOSING IMPORTANT
What is a bacteriocidal drug?
Under ideal conditions, kill bacteria.
What areas are difficult to access in pharmacokinetic terms?
Brain, Eye, Prostate, Bronchus, Mammary gland, intracellular, any poorly vascularised tissue (bone, heartvalves)
How can areas difficult to access be accessed?
By using drugs with good penetration, that are lipid soluble.
What drug is it important not to use for surgical prophylaxis?
Amoxycillin/Long acting amoxycillin
When is it appropriate to use antimicrobials as surgical prophylaxis?
Patient has leukopenia, contaminated surgery, othropaedic, major abdominal or thoracic surgery, surgery >90 minutes (always give before procedure)
