Antimicrobials Flashcards
Is bactericidal better than bacteriostatic?
Nope! Equal
Do greater concentrations kill bacteria faster or in greater numbers?
NOPE
Does vancomycin work on gram-positive or gram-negative bacteria?
gram-positive
What are the 3 main nosocomial infections?
Urinary
Respiratory
Blood
What devices are associated with nosocomial infections?
Ventilator
Vascular access catheter
Urethral catheter
Which central lines cause the most infections?
Femoral> I.J. >Subclavian
Primary cause of c-diff?
clindamycin
What is the treatment for c-diff?
Oral vancomycin
Dificid (fidaxomicin)- similar cure rates as vanco, reduced recurrence for moderate to severe infection
What are the risk factors for c-diff?
Antimicrobial use
Acid suppressant therapy
Inappropriate handwashing and cleaning techniques
Do you always need surgical antibiotic prophylaxis?
NO.
Also, usually not necessary to continue past the 1st Post-op day
Usually use 1st generation cephalosporin (cefazolin)
Wound classification
Class I: Clean (1.3-2.9%)
Atraumatic
No break in sterile technique
Respiratory, G.I., and G.U. tracts not entered
Class II: Clean-Contaminated (2.4-7.7%)
Surgery in areas known to harbor bacteria
no spillage of contents
Class III: Contaminated (6.4-15.2%)
Major break in sterile technique
Surgery on traumatic wounds
Gross G.I. spillage
Entrance into an infected biliary or G.U. tract
Class IV: Dirty-Infected (7.1-40%)
Infection existed before the surgery
Old wound with devitalized tissue
Perforated viscera
Is prophylaxis for fungal infections proven to always work?
Efficacy of prophylaxis is difficult to prove
When do you give ancef, and when do you give vanco for prophylaxis?
Ancef 60 minutes
Vanco 120 minutes
Is increasing duration of antimicrobial prophylaxis associated with higher odds of AKI and C difficile infection in a duration-dependent fashion?
YES. Increasing prophylaxis is bad.
What is the half life of cefazolin, clindamycin, and vanomycin?
Cefazolin: 2 hrs, so dose at 4hrs
Clindamycin: 3 hrs, so dose at 6 hrs
Vancomycin: 12 hours..so..unecessary
Do beta-lactamase Inhibitors have any antimicrobial effect on their own?
NO
Which group of antibiotics causes Jarisch-Herxheimer rxn – looks like a tick infection (high fevers and rash)?
Penicillins
Do patients with a penicillin allergy have an increased risk of SSI?
YES, about 50% higher
Which antibiotic can you give if someone has a penicillin allergy?
Cefazolin
Vancomycin
Which infections are higher in patients with a penicillin allergy?
MRSA and C.difficile
What are the two strongest cephalosporins that cover basically everything?
Ceftaroline (Teflaro) and Cefiderocol (Fetroja)
What is the drug of choice for MRSA?
Vanco
Side effects of vanco?
Red-Man, nephrotoxicity, ototoxicity, TTP (thrombocytopenia)
Which antibiotic can cause serotonin syndrome because of an interaction with MAO, and also causes myelosuppression (anemia, leukopenia)?
Linezolid (Zyvox)
Which antibiotic can cause QT prolongation?
Azithromycin (Zithromax)
Macrolides (azithromycin, clarithromycin, erythromycin)
Which antibiotic is a potent inhibitor of cyp3a4?
Which antibiotic can prolong QT?
Cypa3a4 - Clarithromycin (Biaxin)
Prolong QT - azithromycin
Macrolide family
Which antibiotic has increases the risk for tendonitis – rupture of achilles tendon, neurologic – seizures, confusion, and severe hypoglycemia and increased Morbidity/mortality
Fluoroquinolones
Which antibiotic should be last line because of the multiple FDA warnings?
Fluoroquinolones
Which fluroquinolone is the first fluoroquinolone antibiotic with activity against methicillin-resistantStaphylococcus aureus(MRSA) and, unlike the other fluoroquinolones, is not associated with QT prolongation or photosensitivity.
Delafloxacin (Baxdela)
Dela”firstfluroquinolone”oxacin
Which antibiotic causes inhibition of bone growth (2nd/3rd trimester through the age of 8), hepatotoxicity, tooth discoloration and enamel hypoplasia
Tetracyclines
(doxycycline)
Which antibiotic works on acne but has a host of negative side effects?
Doxycycline (Vibramycin)
Tetracycline family
Which antibiotic interferes with DNA synthesis….Not enough folic acid
Trimethoprim/Sulfamethoxazole (Bactrim, Septra)
Aminoglycoside
Which med is used for patients with implanted device that is growing biofilms over it
Rifampin and Rifabutin
Also a potent inducer of the CYP 450 system with significant interactions
Rare hepatotoxicity, **orange-red body fluids
*Mostly for TB and prosthetics
Which antibiotics are safest for use in pregnancy?
Penicillins, Cephalosporins, Erythromycin
Which antibiotic in pregnant women is associated with acute fatty necrosis of the liver, pancreatitis, and possible renal injury?
Tetracycline
Which antibiotics should you avoid in pregnancy?
Metronidazole, ticarcillin, rifampin, trimethoprim, fluoroquinolones, and tetracyclines
What should you think when you hear antifungals?
anti-fungal – think drug interactions
