Principles Of The Treatment Of Infections Flashcards
Which antibiotic to use
Depends on the patient, the bacteria, and antimicrobial
What is the criteria for treatment
Clinical evaluation
Laboratory evaluation
MIC
Minimum inhibitory concentration
The dilation of antibiotics that just prevents growth
Limits of the efficacy of antimicrobials
Speed of action - bactericidal important in endocarditis, neutropenic sepsis Sensitivity of target - spectrum of activity - penicillin works on gp A streptococci not e. Coli Adverse events - penicillin hypersensitivity - nephrotoxicity with gentamicin
Synergism of antibiotics
Combined effect of both antimicrobials greater than alone
Antagonism of antimicrobials
Combined effects is less
E.g. Penicillin with chloramphenicol (blocks protein synthesis slowing cell growth therefore penicillin cannot work
Indifference with antimicrobials
Each drug works no better alone or together
Routes of administration
Topical
Oral
IV
IM
What bacteria causes surgical site infection
Staph aureus
Coagulase negative staphlococci
Enterococcus
E. coli
Increasingly caused by antimicrobial resistant bacteria
What determines the Choice of the antiobiotic
Safe
Spectrum of activity that reflects bacteria found locally - community not hospital
Matched pharmacokinetics
Reasonable cost per dose
Cephalosporins most commonly used (wound infection)
What do antibiotics do
They have selective toxicity
They kill or inhibit growth of micro organisms and have little effect on humans
Efficacy of antibiotics is influenced by
Bacteria: species, presence of resistance mechanisms
Host: site of infection, metabolism/distribution
Antibiotic: activity against different bacteria pharmacokinetics
