1. Microbe
    unicellular or multi cellular organism capable of producing disease
  2. Antimicrobial therapy
    • Use of medications to treat infections caused by bacteria, viruses and fungi 
    • selective toxicity- it will kill microbe but wont harm the host cell
    • classified 
    •   MOA
    •   susceptibility- can the drug kill the bug
  3. Purpose of antimicrobial
    • we want the maximal effect with minimal harm
    • most appropriate antimicrobial for the pt

    always remember we want to match the bug to the drug or the drug to the bug

    • cautious use- your body maybe able to fight off the bacteria- this is to avoid resistance to the drug. too much exposure to the drug will cause the bug to change 
    • another cautious use is side effect- we want to reduce side effects as much as possible
  4. Selection of the drug
    • 1. ID of pathogens- culture and sensitivity and other times it is by s/s
    • 2. determine sensitivity of the microbe- will be the bug kill the drug
    • 3. site of infection- can the drug get to the bug fat soluble (can cross blood brain barrier), if water soluble it wont cross to the brain if infection is there (abcess can be an issue)
    • 4. Host defenses- 
    • 5. age- elderly and young 
    • 6. health status immune
    • 7. allergy- always ask what is their allergy
    • 8. cost- want the cheapest treatment
  5. Antibiotic combination usage
    • most often we use two types of drugs
    • serious infection

    initial therapy of severe infection- someone who  is becoming septic (germs in the blood stream)

    mixed infection- more than one organism

    enhance antibacterial action- usually related to serious infection or for a pt with a compromise immune system. give two antibiotics that work differently for different things

    reduce s/e and toxicity
  6. Prophylactic Use (preventive)
    30-40% pt use antibiotics for prevention

    1. surgery- especially before the surgery to prevent any diseases. ortho, cardiac right before u go to the O.R. in the recovery as well

    2. recurring UTI

    3. exposure to a STD

    5. bacterial endocarditis (teeth cleaning fillings- bacteria dislodges from the mouth and can travel by the blood stream..bacteria will go to these valves and can cause endocarditis)
  7. Antimicrobial Resistance
    a microbe can become less susceptible, loses its sensitivity to the drug

    impaired response to a dose that is normally effective ie reoccurring UTI

    resistance is the microbe not the pt
  8. why does microbial drug resistance occur?
    • alteration in function or structure of microbe- bug the change 
    • many different ways
    • 1. develop drug metabolizing enzymes
    • 2. cease uptake of certain drugs - wont allow drug to get into the cell
    • 3. change the structure- changes in cellular receptor
    • 4. synthesizes compounds that antagnize drug actions

    ** the bug changes**
  9. Does antibiotic usage promote resistance?

    the use of antibiotic promotes the emergence of drug resistant microbes

    more likely with broad spectrum agents- antibiotics treated for various things (exposure to all sorts of drugs more so for long term use)

    match the bug to the drug
  10. Can we delay the emergence of drug resistance

    prescribe only when clinically needed

    Narrow spectrum agents

    reserve usage of newer agents-
  11. Superinfection
    a new infection that appears during the course of treatment for a primary infection 

    second infection (ie being treated for strep and now u have thrush)

    • antibiotics eliminate the inhibitory influence of normal flora (probiotic)
    • secondary infection will grow and expand
    • difficult to treat
    • more common with broad spectrum agents
  12. example of secondary infections
    • c. diff
    • yeast infetions
    • pseudomonas infections- negative bacteria
    • fungal infection

    wipe out the normal flora and secondary infection can occur
  13. C. Difficile
    • spore gram positive bacteria
    • most common causes of diarrehea, loose stools and a hospitalized pt
    • can be part of normal flora
    • use of antibiotics can increase ur chance of getting it- because it wipes out the normal flora
    • who is at risk
    • long term antibiotic users
    • elderly, compromised immune system (HIV), chemo, long term PPI (wipe at acid), increase hospital stay
    • SE- diarrehea, explosive, smelly odor
    • two toxins A- copous secretions loose stool toxin b- damages the GI lining
    • DX- stool sample
    • prevention- wash hands (no santizer), bleach area. decrease use of antibiotics. mild cases stop antibio
  14. Nursing interventions for patients on antimicrobial therapy
    • Assessments- early identify, s/s, culture, for drug resistance
    • pt teaching
    • - proper hand hygiene
    • - current immunization
    • - take full course of antibiotics
    • - decrease risk of infections
    •     decrease invasive procedure
  15. Penicillins
    • Highly effective
    • one of the oldest antibiotic classes
    • low toxicity
    • not a high risk for side effects
    • contains a Beta lactam ring- where the power is.. as long as this ring is in tact the drug has the power (who has the ring has the power
    • use: use strept infection gram positive bacteria (FYI)
  16. Penicillins MOA
    • disrupting the cell wall
    • weaken the cell wall causing the contents to leak out, cell to rupture- cell lysis (explode) and cell death

    • work on the cell wall creates holes in the cell wall and contents leak out. 
    • binds to protein targets on the bacteria called PBP (penicillin protein binding)
    • - inhibits transpeptidases (make the cross bridges to make the wall strong)
    • - activates autolysins (activites enzymes to make holes) which gives u more holes in the bacteria
    • end results the bacteria contents falls out and the cell dies
  17. AP review Bacteria
    Bacteria are surrounded by rigid cell wall

    gram positive bacteria- 2 layers thick cell wall

    gram negative bacteria- 3 layers thin cell wall
  18. Penicillins Spectrum
    Spectrum: Fast growing gram positive bacteria

    best against gram positive bacteria because it only has two layers

    • classifications:
    • Narrow Spectrum (P sensitive): sensitive to penicillianase will detroy beta lactum ring and make the drug ineffective. 
    • Narrow Spectrum (P resistant)- drug is resistant to penicillinase
    • Broad spectrum- gram +/- (sensitive)
    • extended spectrum- gram +/- others (sensitive)
  19. Bacterial Resistance
    1. Inability of penicillins to reach the PBPs gram negative bacteria (because it has three layers and it is difficult for it to get thru all three layers)

    2. Beta lactamases (penicillinases) enzymes produce by bacteria that will make holes in the drug
  20. Penicillins Side effects
    • 1. Hypersensitivity (allergy)
    • 2. Hematological- cause platelet disfunction, thromsipenia (increase risk for bleeding)
    • 3. GI
    • 4. Renal impairment (assess BUN/creatinine)
  21. Penicillins NI
    Assess for drug allergy and cross sensivity (b/c pt may also have an allergy to other antibiotics with a beta lactum ring) cepholosoprins example 

    • assess the pt 1 hr after administer
    • assess renal function, platelets count
    • asses side effects

    • drug interaction 
    •     Aminogylcosides IV- penicillins inactive drug so we cant give in the same line Separately two different line/ flush
    •    Antacids (po) decreases absorptions
    •    bacteriostatic antibiotics (slows the growth) penicillins likes fast growing bacteria
    •   Probenecids (gout)- uric acidic agent- delays the excretion of penicillins. it keeps antibiotic longer in the body and prolongs the effect nclex/ati
  22. Penicillins  combined with a Beta lactamase inhibitor
    • 2 antibiotic
    • Combined Beta lactamase inhibitor with a penicillinase sensitive
    • extends the antimicrobial coverage
    • S/e- similar to penicillin
  23. Cephalosporins
    • Similar in structure and action to penicillin
    • - beta lactam antibiotic
    • most widely use antibiotic
    • toxicity is low
    • MOA similar to pencillins 
    •  CBP
    • Spectrum- actively growing bacteria
  24. Classification (generations)
    • there are 4 generations
    • Age: 1st Old 4th New
    • Cost: 1- cheap  2. expensive
    • Spectrum 1. gram + (narrow) 4- gram +/- broad
    • Blood brain barrier: 1- can not cross 4- easy
    • Resistant to beta lactase- 1. destroy drug 4th- resistance cannot be destroyed
    • essay/short
    • u need to know- that we mostly use 1/2 and 4th for cranial infection
  25. cephalosporin se
    • 1. hypersentivity/allergy
    • 2. bleeding cause platelet disfuntion
    • 3. thrombophletis 
    • 4. GI, pseudomembraneous (confusion), colitis
    • 5. Nephrotoxicity (bun/creatinine

    resistance- see penicillins (cephalosporiases)
  26. cephalsporins NI
    • similar to penicillins
    • 5-10% allergic to peniciilins u will be allergy to this and vice versa
    • assess for se
    • oral agents- disulfiram reaction with alcohol
    • give with food to decrease gi effect 
    • IM injection give in large muscle
    • asses for superinfection
    • assess renal function and CBC (platelets)
    • probycid- to prolong the effects
  27. Dislfiram effects with cephalosporins
    • 5ml of alcohol
    • effects the liver and it can't metabolize the cephalosporins
    • Acetaldehde accumulates- hangover
    • results- flushing, tachycardia, n/v blurried vision, hypotensio n
  28. Monobactam antibiotic
    Beta lactam ring

    • MOA: inihibits bacterial wall cell synthesis. narrow spectrum. doesn't bind to protein.
    • can cross over in the cerebral spinal fluid- so can help with menigitis, brain infections, gram negative
  29. Monobactam antibiotic SE NI
    GI, vertigo, headache, and thrombophlebitis

    • NI: not absorbed by the GI tract given by IV, synergistic effect with aminoglycisides/beta lactam antib (enhances the effects these anti). 
    • it is often given with other antibiotics used to (never given alone)
    • careful assess of IV for thrombophlebitis 
  30. Carbapenemas
    • Beta lactam antibiotic
    • - broad spectum
    • - usually given with other antibiotics

    MOA- destroy's bacterial wall

    SE see penicillins

    NI: monitor renal impairment, monitor BUN and creatnine, cross sensitivity of penc and cephalsoporins (allergic)
  31. Vancomycin
    • Works on cell wall synthesis
    • works on the precursor for wall synthesis (building blocks of the wall)
    • High rate toxicity
    • used for serious infection- why would we use this for serious infection- because of the toxicity and resistance

    Very powerful  in destroying bacteria but also has powerful SE
  32. Vancomycin spectrum SE
    Spectrum- gram positive bacteria 

    • SE: ototoxcity cn 8 (1st sign tinnitus), coordination off, nephrotoxicity- this is reversible, these two symptoms go hand and hand
    • Thromphlebitis
    • anaphalytic reaction "red neck syndrome"- this releases histamine which can cause red, hypotension, increase temp, cause fluids to shift
    • rapid infusion reaction- increases risk for thromphlebitis
    • leukopenia- low WBC at risk for infection
    • thrombocytopenia- at risk for bleeding platelet disfunction
  33. Vancomycin NI
    • Assess for allergy/side effects
    • infuse slowly on the pump 1 hr
    • assess IV site
    • monitor therapeutic drug levels prior to the third dose (trough levels) high trough level increases risk for oto/nephrotoxicity
    • assess renal function, hearing
    • elders have a higher risk of toxicity
    • increase risk with nephro/ototoxicty with other meds (penicillins/cephalosporins)
  34. Antibiotics affecting  protein synthesis
    • Aminoglycosides
    • macrolide antibiotic
    • tetracyclines
  35. Aminoglycosides
    Bactericidal- they kill bacteria

    • high risk of SE
    • ex- gentamycin (don't need to know drug)

    • MOA: disrupt protein synthesis, bind to the 30s ribosomal subunit
    • - cause misread of information
    • - cause production of abnormal proteins

    ribosome are building block for proteins...blocks dont line up with protein and cell dies
  36. Aminoglycides spectrum SE
    • Spectrum gram negative bacteria aerobic needs o2.
    • - ineffective against anaerobic bacteria
    • (it needs energy O2 transport to get into the cell)
    • reserved for serious infection

    • SE
    • Ototoxicity, nephrotoxicity
    • neuromuscular blockade-  inhibits the transmission of peripheral nerve impulses, be careful with other  drugs that decrease neuro transmission
    • hypersensitivity
  37. Aminoglycoside NI
    25% of pt on this develop oto/nephrotoxicty

    • assess allergy/se
    • assess drug interaction: oto/nephrotoxicity (cautious for vanco), neurotoxic drugs, skeletal muscle relaxation (because it decreases neurotransmission)
    • assess BUNm creatinine, peak and trough levels
    • well hydrated to prevent renal tuble irritation
    • IV poorly absorbed byt GI tract only give if needed for local effect
  38. Neomycin

    • CI: topical treatment of eye, ear, and skin
    • orally: used locally to decrease bacteria, suppress bowel flora prior to sugery, reduce ammonia forming bacteria in the gi tract (hepatic failure)
    • not admin IV because of high rate for toxicity
    • SE: superinfection of the bowel
    • NI not absorbed in the gi tack
    • - multiple drug interaction
  39. Macrolide antibiotics
    • big molecule antibiotics
    • Bacterostatic and bactericidal (slows down growth and kills)

    MOA: inhibits bacterial protein synthesis
  40. Macrolide antibiotics spectrum SE NI
    • Spectrum- most effective against gram + than gram - 
    • use- resp infection and allergy to penicillins

    SE: GI (nausea, vomiting, change in taste, heptatoxicty

    • NI: depends on specific macrolide whether it should or should be given with food
    • most have long duration of action given once a day
  41. Tetracycline
    • semisynthetic antibiotic
    • bacteriostatic

    MOA: suppress growth of bacteria by inhibiting protein synthesis
  42. Tetracyline spectrum, CI, SE
    Spectrum broad 

    we see this used less and less b/c of resistance 

    CI: infections of urethra, pneumonia, lyme disease, h. pylori

    SE: GI, effects on bone and teeth (decrease enamel esp children and prego), discloration of teeth, suprainfection bc broad spectrum, hepato/nephrotoxicty, photosensitivity
  43. Tetracyline NI
    • assess allergy/se
    • chelation effect- when u give this drug, ca, mg, al, zinc, iron- it binds to the mineral and gets excreted out (common se is GI so u might take meds that have these ie mg so give this after two hours)
    • extreme caution: in children under 8 yrs/preg
    • rinse mouth/use straw
    • best on an empty stomach
    • assess risk of sunburn- use sunblock
    • monitor renal/hepatic function
    • assess drug interactions
  44. Misc. antibiotic
    • Fluroquinolones
    • bactericidal

    MOA- inhibits bacterial DNA gyrase (an enzyme that cause the DNA to coil) so if cell doesn't coil it can not replicate

    • Spectrum: broad, aerobic gram neg bac
    • use for urinary/resp/gi infection
  45. Fluroquinolones SE
    • mild GI most commons
    • CNS: headache, dizziness
    • candida infection pf the mouth and throat, superinfection wipe out normal flora
    • rare- rupture achilles tendon (pain swollen in legs feet.notify md)
    • photosensitivity
  46. Fluroquinolones NI
    • assess allergy/se
    • chelation effects
    • best on empty stomach
    • admins over 1 hr
    • assess drug interaction
    • assess tendon pain or inflammation esp with elders stop dose call md
    • assess photosensitivity, superinfection,
    • not reccommended for peeps under 18
  47. Metronidazole (flagyl)
    • antimicrobial/antiprotozoan drug
    • pro drug
    • anaerbic organism because this can convert this to its active form
    • MOA: it must be taken up by the cell, converted to active form, DNA cant replicate than the cell dies
    • only anaerobes can convert to active form
    • good for abcess, deep wounds, gi effects
  48. Flagyl Spectrum
    know that is good for anaerobic bacteria
  49. flagyl SE NI
    SE: GI, headaches, metallic taste, darking of the urine, 

    • NI
    • assess allergy/ se
    • disulfiram- liver cant metabolize alcohol causes u to have that drunk feeling
    • assess drug interactions
    • IV admins: over 1 hours
Card Set