infection control

  1. *Inhibits enzyme activity
    *Drying of microorganism from a frozen state
    *Drying takes place under a high vacuum which removes water
    *Organisms can remain viable in this state for many years
    *Used to preserve microogranisms
  2. *Affects microbe's nucleic acids impairing microbial functions
    *denatures proteins
    *Used in biological hoods and surgical fields in healthcare
    *Microwave ovens can kill microorganisms however, endospore contain little water and are therefore not destroyed my microwave cooking
  3. *Mechanically removes organisms
    *Requires filters with very small pores
    *Highly-efficiency particulate air (HEPA) filters are used in healthcare ventilation systems to trap organisms
    *Filters are then disinfected prior to disposal
  4. Action against microbe but not harmful to host (patient)
    Selective Toxicity
  5. range of effectiveness
    Spectrum of Activity
  6. contradictions of use
    Side Effects
  7. effect on microbes
    Modes of Action
  8. Microbes resist effects of antimicrobial agent
    Drug Resistance
  9. Level at which the antimicrobial agent will cause host damage
    *Liver and kidney involvement
    Toxic Dosage Level
  10. Level at which the antimicrobial agent eliminates the patogenic organism if the level is maintained over a period of time
    Therapeutic Dosage Level
  11. The maximum tolerable dose per body weight that will eradicate infection
    Chemotherapeutic Index
  12. -Antibiotics that attack a large range of microbial agents
    -May attack gram positive or gram negative organisms
    -Can be ordered after gram stain result of a specimen
    Broad Spectrum
  13. -Attack a much smaller group of microbial species
    -Ordered after susceptibility testing indicates the drug of choice for the pathogen
    -Limits drug resistancy because fewer organisms are eliminated
    Narrow Spectrum
  14. *Penicillin
    Inhibition of cell wall synthesis
  15. *polymyxin
    Distruction of cell membrane function
  16. *Gentamicin
    Inhibition of protein synthesis
  17. *rifampin
    Inhibition of nucleic acid synthesis
  18. *Sulfa agents
    *Isoniazid (INH)
    Function as antimitabolites
  19. -Can adversely affect liver, kidney, central nervous system, hearing, balance, bone marrow, and the gastrointestinal tract
  20. -Mild->rash, swelling, itching
    -Life threatening->anaphylactic shock
    Allergic reactions
  21. -Pathogens and normal flora are destroyed by antimicrobial therapy
    -can give rise to a secondary infection often referred to as a "superinfection"
    Disruption of Normal Flora
  22. microbes migrate out of the reach of the antimicrobials and are not eradicated
    Evasion- Non-genetic Resistance
  23. some microbes can modify their structure which can inhibit the attachment of the antimicrobial agent to the microbe and therefore impair its action against the microbe
    Modify Structure   Non-genetic Resistance
  24. genetic information code for endospores or capsules can inhibit the action of antimicrobials
    Plasmids   Genetic Resistance
  25. transfer of resistant genes from one organism to another
    Mutations   Genetic Resistance
  26. *Do not over use Antibiotics
    *use Narrow Spectrum Antibiotics
    *Be compliant and take the antibiotics for the complete duration of the prescription
    Minimixe Drug Resistancy
  27. Purpose is to determine the appropriate antibiotic that will eradicate an infection
    -disk diffusion
    -tube dilution
    Susceptibility Testing
  28. *Based on a theory that a specific amount of drug will diffuse on a culture media that has been inoculated with a blanket of microbial growth and that zones of inhibition around the drugs will determine the effectiveness of the drug to treat the microbial agent
    *Qualitative measurement
    -The validity of the procedure lies with standardizations that must be followed precisely to achieve accurate results
    Disk Diffusion Susceptibility
  29. -Agar used is Mueller-Hinton (enrichment media)
    -Increased volume of agar causes decrease diffusion rate of drugs resulting in smaller zones of inhibition
    -Decrease volume of agar causes increased diffusion rate of drugs resulting in larger zones of inhibition
    Volume of Agar
  30. -increased concentratioon of the organism results in overgrowth of the organism and smaller zones of inhibition
    Amount of Organism
  31. -Disks are impregnated with specific concentrations of a drug which correlate with established zones of inhibition used for the reporting system of this method
    Amount of Antibiotics
  32. Overnight incubation to allow organism to grow
    Time of Incubation
  33. 35'C-37'C
    Incubation Temperature
  34. indictates that a drug will be able to eradicate an organism if patient is compliant
    Sensitive (S)
  35. indicates that a drug may work if combined with other anitmicrobials to increase its' effectiveness (synergism)
    Intermediate or Moderately Sensitive (I/MS)
  36. indicates the drug will not be effective in eradicating infection
    Resistant (R)
  37. *Based on the same theory as the disk diffusion test except that the method uses a liquid medium to determine drugs of choice to eradicate infection
    *Quantitative measurement (an actual number)
    *Standards are similar to disk diffusion test
    -Amount of Organism
    -Amount of Antibiotic
    -Time of incubation
    -Incubation Temperature (35'C-37'C)
    Tube Dilution Susceptibility
  38. minimum concentration of a drug that will prevent visable growth of the organism
    Minimal Inhibitory Concentration (MIC)
  39. minimum concentration of a drug that shows no growth from a tube when subcultured
    Minimal Bactericidal Concentrtaion (MBC)
  40. *Selectively Toxic
    *Soluble in Body Fluids
    *Easily maintained at therapeutic dosage levels
    *Does not elicit drug resistance
    *Long shelf-life
    Criteria for Ideal Antimicrobial
  41. -Thickens cell wall interfering with the intake of nutrients
    -Increases cell wall permeablility
    -Inhibits nucleic acid syntheis
    Amphotericin B
    Nystatin (very effective for a yeast infection)
    Antifungal Agents
  42. -Inhibits some phase of replication
    -Inhibit attachment of virus to host cell
    -Inhibit penetration of virus into host cell
    Interferon- naturally produced antiviral agent
    Antiviral Agents
  43. -Interfere with protein synthesis
    -Interfere with folic acid synthesis
    Metronidazole (Flagyl)
    Antiprotozoan Agents
  44. -Interfere with carbohydrate metabolism
    -Paralyze worms (neurotoxins)
    Mebendazole (Vermox)
    Piperazine (Antepar)
    Antihelminthic Agents
Card Set
infection control
Infection Control Review