Aminoglycosides Flashcards
Binds to outer membrane of cell resulting in LPS rearrangement. Uptake is dependent upon energy from electrochemical gradient of bacterial cell. Trapped inside once across cytoplasm
Aminoglycoside
Binds to 30s and 50s leading to decreased protein synthesis and misreading of mRNA
High intracellular concs
Aminoglycoside
Batericidal or static?
Concentration or time dependent killing?
PAE or no PAE?
Cidal
Conc. dependent killing
PAE
Well absorbed or poorly from GI tract?
Poorly - aminoglycoside
Distributed freely or unfreely into vascular space?
Conc. in lungs are ________ of those in serum
Distribution to CSF _______ with inflammation
Freely
25-50%
20%
Excretion?
Low or high urinary conc?
Renal
High
Elderly (Vd and Ke)?
Decreased
Critically ill (Vd and ke)?
Change in Vd
Renal disease (Vd and Ke)
Decreased Ke
Change in Vd
Cachexia/Malnourished (Vd and ?)
Decreased Vd and creatinine production
Amputated limbs (Vd and Ke)?
Decreased Vd
Aminoglycosidic aminocyclitols
6 membered aminocyclitol ring (amino and non-amino containing sugars attach to ring by glycosidic linkages)
Aminoglycosides
Desired peak? Trough?
4-12 or 20-30
Less than 2
Too high peak can cause
Too high trough can cause
Otoxicity (8th CN)
Nephrotoxicity
Only aminoglycoside available orally? Rest are IV and IM
Neomycin
Substantial variations existing in concentrations achieved compared to what was predicted?
Nomogram
7mg/kg for first dose then assess levels 6-14 after dose
Hartford nomogram
___________ doses may be equally as effective as smaller multiple doses with __________ toxicity. Relies on PAE
Large daily
Less
Narrow or broad therapeutic index?
Narrow
