RavLect14: AGs Word Scramble
|
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Question | Answer |
Aminoglycosides | Gentamicin Tobramycin Amikacin Streptomycin Neomycin (only used topically) |
AG MoA | IRREVERSIBLY bind to bacterial ribosome 30S to inhibit protein synthesis Ionic interactions w/ cell wall; mostly CIDAL |
AG disadvantage | Renal toxicity; must monitor SCr daily against BUN (big hassle!) |
AG PK (linear) | Concentration Dependent w/ Post-ABx effect 1-compt model; H2O distribution Standard dose = multi-dose vs Once-daily dosing = big dose (safer for kidneys) Do NOT distribute into pus, abscess, & fatty tissue (poor for anaerobic Tx) Poor CNS di |
Formulas for AG dosing | T ½ = 0.693/Kd Vd = 0.25L/Kg (use adjusted BW if obese) Kd(hr –1 ) = Cl (L/hr)/VD (L) LD (loading dose) = (desired AG serum conc.)CPss*(VD |
Cockcroft-Gault formula for eGFR | [(140-age)*(kg)*(0.85 if female)]/[72*Scr] ml/min -> liters/h: multiply by 0.06 to put into Kd eqn |
AG SoA | Combo synergistic therapy, except in kidneys/urine G-: SPACE M. tuberculosis Mycobacterium Avium- intracellular MAI or MAC G+: Enterococci, Streptococci, Staphylococci, Listeria Do NOT cover strict anaerobes (B. frag) without facilitation. |
AG ADRs | 1) Nephrotoxicity (ATN-acute tubular necrosis, Fanconi's syndrome-casts w/ nonoliguria) 2) Otoxicity (Hearing, vestibular balance problems -> N&V) be careful with Platinum agents and Vinca alkaloids 3) Neuromuscular blockage 4) DDI w/ PCN; Don't |
AG Combos (good against anaerobes & harder for resistance to develop b/c different MoA) start as empiric therapy, then drop the AG drug b/c it works slower than the other b-lactam drugs | w/ b-lactams (PCN or Amp) for Enterococcus- gent preferred. If resistanct, use w/ vancomycin or linezolid w/ vanco & rifampin for coag (-) staph endocarditis. w/ antistaph PCN for S. aureus endocarditis Listeria: Gent+Amp is 1st line (2nd line: Sep |
Clinical Use of AGs | Gram (-) Nosocomial (hospital/ventilator associated) pneumonia, bacteremia, pyelonephritis, urosepsis, sepsis serious polymicrobial infections |
Conventional or Multiple dose (Standard Dose) | Urinary, Tissue, Lung/blood respectively: 1(synergistic dose), 1.5, 2mg/kg for Gent & Tobramcyin 5, 6, 7 mg/kg for Amikacin |
Standard Dose Levels, time to gather | Drug Levels: Usually obtained after the 3rd dose Peak: obtain 30 min after a 30 min infusion or 15 mins after 60 min infusion Trough: just prior to the 4th dose |
Standard Dose: Gent/Tobra Peaks & Troughs | Peaks: Urinary tract infections 3-5 mcg/ml Skin & soft tissue infection 5-7 mcg/ml Pneumonia & sepsis 7-10 mcg/ml Trough: <2 mcg/ml |
Standard Dose: Amikacin Peaks & Troughs | Peaks: Urinary tract infections 25 mcg/ml Skin & soft tissue infection 30 mcg/ml Pneumonia & sepsis 35 mcg/ml Trough: <10 mcg/ml |
Peak & Trough problem? | Too high peak will harm ears Too high trough will harm kidneys |
Once Daily (High Dose, Single Dose, or Extended Interval Dosing) | Gent/Tobra: 7mg/kg Amika: 15 mg/kg for peak of about 20mcg/ml or 60mcg/ml Based on actual body weight unless >20% IBW then use an adjusted weight Check random level after the 1st dose between 6-14 hr. NOT a trough/peak. |
Once Daily Dosing Interval | CrCl 60 ml/min: Q24H CrCl 40-59 ml/min: Q36H CrCl 20-39 ml/min: Q48H CrCl <20 ml/min: monitor serial levels Follow Hartford protocol! Out of bounds, stop drug! |
When to NOT use once daily dosing? | Enterococcal endocarditis Pregnancy Select Pediatric Populations Cystic fibrosis Burns Renal failure (CrCl<10) |
Synergy doses | Do NOT require levels but UTI infection dosing at 1mg/kg requires levels to assure efficacy |
AG drug comparisons | G- (SPACE): Tobramycin>Gent (Amikacin most potent, but very restricted use b/c toxic). Needs combo for anaerobic B. frag. G+: Gent has best activity. Combine w/ b-lactams for Entercoccus, Strep, Staph, and Listeria. |
Created by:
cheeoh
Popular Medical sets