Exam V - Antibiotics Flashcards
_______ _______ is almost always the first step in the identification of a bacterial organism
Gram stain
staining with crystal violet dye differentiates bacteria by the chemical and physical properties of their cell walls by detecting _____________
peptidoglycan
Peptidoglycan is present in a THICK layer in gram-_________ bacteria
positive
Gram-________ bacteria retain the crystal violet dye
positive
Gram-__________ bacteria stain a red or pink coloring 2/2 a counterstain (commonly safranin or fuchsine)
negative
(t/f) Antibiotics save more lives than any other class of drugs
true
Which two classes of bacteria cannot be definitively classified by the gram-stain procedure
Gram-variable
Gram-indeterminate
_________ bacteria require O2 to live, and __________ bacteria cannot live in the presence of O2
Aerobic
Anaerobic
Purple bacteria is which type?
Gram-positive
Pink/red bacteria is which type?
Gram-negative
Steps of the gram-stain procedure
- crystal violet
- Iodine
- alcohol wash (decolorization)
- Safranin (counterstain)
Why do you have to continue taking Abx’s for the full schedule of your prescription?
Compliance with proper time intervals maintains the MEC/MIC (minimum effective/inhibitory concentration)
Lowest concentration of an ABX that prevents visible growth of microorganisms
MEC/MIC (minimum effective/inhibitory concentration)
What is the most common cross-sensitivity that we will deal w/ all the time in the OR?
Cefazolin (Ancef) and Penicillin
Units used to quantify vitamins, hormones, some medications, vaccines, blood products, and similar biologically active substances.
IU (International unit)
Acute infections MEC day range is average ___-___ days or until the patient is asymptomatic/afebrile for ___-___ hours
7-10 days
48-72 hours
Oral bioavailability greater than ___% for most antibiotics
70%
sulfonamides are ______ soluble and are used to treat _______
Lipid soluble
UTIs
Inhibitors of folic acid & nucleotide biosynthesis is the MOA for what Abx?
Sulfonamides
*Folic acid & fonamides (F&F)
Which abx’s are bacterial cell wall synthesis inhibitors?
Penicillins
Aztreonam
Vancomycin
Cephalosporins
-Reaking PAVC on the cell walls
Which Abx’s are inhibitors of DNA replication & RNA synthesis?
Quinolones (cipro)
Rifampin
*DNA/RNA is the QR code for our body
Never give _________ fast in peds pts b/c it’s ototoxic
Gentamicin
Which abx’s are protein synthesis inhibitors?
Tetracycline
Aminoglycosides
Microlides
Isoniazid
*TAMI hates protein
*This A is w/ an M in TAMI for AMinoglycosides
*AND Clindamycin (TAMI & LINDA hate protein)
3 things you have for true anaphylaxis
-angioedema
-bronchoconstriction
-pruritis (central mediated itching, nothing to do w/ histamine)
Vancomycins + Furosemide/ASA = increased ___________
ototoxicity
*think ototoxicity w/ LASIX
Cephalosporins interfere with ________ metabolism
ethanol
*Can’t give ur Ancef w/ drunk pt before surgery
Tetracylcines reduce the effectiveness of _________ _____________
oral contraceptives
What 2 abx types are you gonna give for initial therapy before culture reports come back?
Single Broad Spectrum
Combination ABX
Most laboratory tests to ID an organism take ___-___ hours (except for gram-stains)
48 - 72 hrs
__________ ID’s the causative organism
Culture
___________ tests determine which drug is likely to be effective against the organism
Sensitivity
*which drug is this organism going to be SENSITIVE to
Culture & sensitive especially important with gram-________ bacteria due to the high incidence of drug-resistant organisms
negative
What bacteria is often responsible for UTI’s
E.Coli
*shit going to the urethra
Many ABX are _______ excreted and therefore effective against ______
Renally
UTI’s
Prophylactic Therapy in
perioperative infections in high risk clients helps _________ resistance
*BLUE BOX
decrease
What are the 4 high risk surgical procedures
*BLUE BOX
-Cardiac
-GI
-Transplants
-Orthopedic (hardware)
What is the 1st Generation Cephalosporin with activity against Staph Aureus or Strep that we use for pre-op?
You know this
Cefazolin (Ancef)
Intraop Cefazolin (Ancef) given every ___ hours
4 hrs
Repeat administration is recommended after_______mL of EBL or volume loss of __%
1500mL
OR
20%
(t/f) Your repeat abx dose is the same as your first dose
True
normal flora of skin and upper resp tract
Staphylococci
normal flora of throat/nasopharynx
Streptococci
normal flora of human intestine
Enterococci
Is there a repeat dose for Vancomycin?
NO
*1 dose per 24hrs
Pt has a rash w/ PCN allergy. Can you give Ancef?
Yes
Pt has anaphylaxis w/ PCN allergy. Can you give Ancef?
NO obviously
Pt has allergy to PCN but s/s not documented. Ok to give Ancef?
No
Staphylococcus _________: boils, carbuncles, burn & surgical wound infections
aureus
*normal staff infections not caused by pieces of equipment
Staphylococcus _________: endocarditis, bacteremia.
Infections associated with the use of treatment devices
Non-aureus
Streptococcus ___________: pneumonia, sinusitis, otitis media, meningitis
Pneumoniae
*think pulmonary infections
Streptococcus ___________ (beta-hemolytic strep):
-Severe pharyngitis “strep throat”
-Scarlet fever, rheumatic fever, endocarditis
pyogenes
*scarlete & rheumatic FEVER from PYROGENIC agents
What type of bacteria:
Nosocomial (hospital acquired) infections
Secondary invaders in wound infections and UTI’s
Also found in soil, food, water and animals
Enterococcus faecalis & faecium
Staphylococci
Streptococci
Enterococci
Gram + or -?
positive
Bacteroids
Escherichia Coli
Klebsiella
Proteus
Gram + or -?
negative
Which bacteria?
Anaerobic bacteria in digestive, respiratory, and genital tracts
Bacteremia
Abscesses: intra-abdominal, pelvic, and brain
Bacteroids
*bacteroid=brain (BB)
Which bacteria?
Normal to the intestinal tract
UTI’s, pneumonia, sepsis, diarrhea, dysentery, hemorrhagic colitis
Escherichia Coli (E-coli)
Which bacteria?
Normal bowel flora
Infect respiratory tract, urinary tract, bloodstream, burn wounds, and meninges
Pneumonia, bacteremia, sepsis
Klebsiella
Collin’s notes: if you see a question about a fistula infection, which bacteria?
Klebsiella
Fist-ula = Kelbsie-lla
What 4 bacteria can cross BBB?
Gram +
-Streptococci
Gram -
-Klebsiella
-Pseudomonas
-Bacteroids
*SKPB - Strep Kills People’s Brains
Pseudomonas _____________ is resistant to many antibiotics and can get to the brain
Aeruginosa
Cocci bacteria are the gram-________ bacteria
Positive
*Coccs are positive
Which bacteria? (hint: gram -)
Nosocomial infections:
UTI, respiratory tract, skin, burn wounds, & bloodstream
Serratia
Which bacteria?
Diarrhea to severe dysentery after ingesting contaminated food or water
Shigella
All beta lactam compounds have a
___ membered beta lactam ring
4
*its the SQUARE in the compound stucture (has 4 sides)
*could be a hotspot question
Penicillins
Cephalosporins Monobactams Carbepenems
Beta Lactamase Inhibitors
These are all _______ _______ compounds and have cross-sensitivity
Becta-lactam compounds
Vancomycin is in what class?
Glycopeptide
The outer membrane, a lipid bilayer, is present in Gram-__________ but not Gram-__________ organisms
negative
positive
The lipid bylayer of the gram-negative bacteria is penetrated by ______ which are proteins that form channels providing hydrophilic access to the cytoplasmic membrane
porins
The peptidoglycan layer is unique to bacteria and is much thicker in Gram-_________ organisms than in Gram-________ ones.
positive
negative
__________ __________ _________ are membrane proteins that cross-link peptidoglycan (AKA make the peptidoglycan layer)
Penicillin-binding proteins (PBPs)
(t/f) Beta-lactams work on both gram-positive and negatvie bacteria
true
*both + & - have peptidoglycan
Beta-lactams act by binding to _______ _______ ________
This interferes w/ ___________
Which is required for the PBPs to build the cross-links in the peptidoglycan (aka cell wall synthesis)
PBPs
Transpeptidation
(t/f) Beta-lactams are only effective only when bacteria are actively growing and synthesizing a cell wall.
True
*remember they affect CELL WALL SYNTHESIS
________ perform transpeptidation in bacteria
PBPs
Look @ slide 24 and note the difference btw gram-positive and gram-negative bacteria structures
Do it
What are 4 ways that resistance can be formed to beta-lactams?
***Inactivation of ABX by β-lactamases (most common)
-Modification of target PBP’s
-Impaired penetration of ABX to the target PBP
-Efflux
Staph Aureus
Haemophilus Influenzae E.Coli
These 3 bacteria can secrete ____________, which is the most common reason for the resistance of beta-lactams
Beta-lactamases
*SHE lactates beta-lactamases
Abx class of choice in individuals with a history of penicillin allergy OTHER THAN AN IMMEDIATE HYPERSENSITIVITY?
*BLUE BOX
Cephalosporins
(1st gen is Ancef)
Pencillin & cephalosporins are what kind of abx’s?
Beta-lactams
Which beta-lactam abx class is less prone to being innactivated by beta-lactamases
Cephalosporins
Is cefazolin (ancef) useful in meningitis?
no
doesn’t cross BBB
__________ – only IV 1st Generation Cephalosporin in use within the US
Cefazolin (ancef)
First-generation cephalosporins are active predominantly againstGram-_________bacteria, and successive generations have increased activity againstGram-__________bacteria (albeit often with reduced activity against Gram-positive organisms).
positive
negative
any bacterium that has a spherical, ovoid, or generally round shape
Cocci
Rod-shaped bacteria
Bacillus
1st gen Cephalosporins work best w/ which bacteria?
Gram +
Pneumonococci
Steptrococci
Staphylococci
*cocc’s
*The reason we give Ancef all the time in the OR is b/c the 2 big bacteria we worry about during surgery is STREP & STAPH and Ancef covers those gram + bacteria
Which gen cephalosporins have extended gram negative coverage
2nd gen
(t/f) 2nd gen cephalosporins can cross BBB
True
What class is Cefuroxime (Zinacef)
2nd gen cephalosporin
Which gen cephalosporin is best for treatment against commonly acquired pneumonia
2nd gen
*you get pneumonia in ur 2 lungs (2nd gen)
Ceftriaxone (Rocephin) or Cefotaxime are what gen cephalosporins?
3rd gens
*Triaxone (Tri=3)
Are beta-lactams bacteriostatic or bactericidal?
Bactericidal
Which beta-lactam abx has no cross allogenicity with PCNs
Aztreonam (Azactam)
_____________ is a beta-lactam can be given PO and is avoided IM d/t pain
Cefuroxime (zinacef)
*XIM (NOT give IM)
(t/f) Piperacillin/Tazobactam (Zosyn) works on both gram positive and negative
True
Neuromuscular Hypersensitivity can be commonly cause by what abx class
Beta-lactams
What is the only glycopeptide abx
Vancomycin
This abx can cause “Red Man’s Syndrome”
Vanc
Inhibits cell wall synthesis by binding to the D-Ala-D-Ala terminus of nascent peptidoglycan
Vancomycin
Vancomycin kills staphylococci relatively ______ than beta-lactams
slower
__________ + ___________ = treatment for enterococcal endocarditis if you have serious penicillin allergy
Vancomycin + Gentamycin
Pre-op Vancomycin dose is what
15mg/kg
*in order to drive a VAN, you gotta be 15 yo (learners permit)
What is the only abx that is bacteriostatic?
Clindamycin
With vancomycin, __________ is a rare complication & __________ is a common complication
Ototoxicity
nephrotoxicity
You worried about kidneys w/ Vancomycin?
Yep
Which abx you gonna need for the dentist if you are trying to prevent endocarditis if you have a valvular heart disease and have a PCN allergy?
*BLUE BOX
Clindamycin
Enterococci(+) and Gram (-) bacteria are resistant to __________
Clindamycin
Gram (-) have an outer membrane resulting in poor permeability of __________
Clindamycin
Clindamycin is only useful for gram-________ bacteria except for ___________
positive
enterococci
What abx for skin & soft tissue infections - MRSA
Clindamycin
What abx’s can cross BBB? (only ones on the PP)
-2nd & 3rd cephalosporins
-Cipro
What is the only abx in the Lincosamides abx class?
Clindamycin
*LINda (duh)
Do you need to do dose change in renal pts w/ clindamycin?
Nope
Which abx is the aminoglycoside?
Gentamycin
*GYMtamycin & aminos/protein
This abx has synergistic effects when combined with β-lactams or Vanco
Gentamicin
*think about endocarditis tx. w/ PCN allergies (Vancomycin + Gentamicin)
This abx has synergistic effects when combined with β-lactams or Vanco
Gentamicin
Which abx has concentration dependent killing with significant POST-ANTIBIOTIC effect
Gentamicin
*You get ur POST GYM PUMP after ur GYMtomysin w/ ur aminos/protein
This abx can cause ototoxicity that is IRREVERSIBLE d/t nerve injury. Can cause Vertigo
Gentamicin
*dropping weights in the GYM is too loud and causes ototoxicity IRREVERSIBLE
Which abx is the fluoroquinolone
Ciprofloxacin
Inhibits DNA replication by binding to DNA gyrase and topoisomerase IV
(2 sites of action and works on both 2 types gram + & -)
Ciprofloxacin
*PRO tennis takes 2 players
*gyro toppings (DNA gyrase & topoisomerase IV)
*causes TENdonitis in ankles
Which abx is a Nitroimidazole
Metronidazole (Flagyl)
*DAZOLE Flagyl
Which abx causes a disulfuram like reaction when given with alcohol
Metronidazole (Flagyl)
*can’t be drinking while putting up a flag
This abx MOA is via disruption of electron transport chain
Metronidazole (Flagyl)
*be careful putting up the flag (NOT DRUNK) b/c you can get ELECTROCUTED
Which abx for planned or unplanned disruption of the bowel?
Metronidazole (Flagyl)
*People SHITTING their pants in the METRO
