final part 2 Flashcards
AG spectrum of activity
- gram - aerobes
- gram + organisms
- sepsis/ abdominal/ respiratory tract/ SSTI/ endocarditis/ CNS/ UTI
AG efficacy monitoring
peak
AG toxicity monitoring
- trough
for EXTENDED interval what weight do you use?
- actual BW unless >120% IBW
which drugs do you use population based dosing?
- gentamicin & tobracycin
Ro=
mg/hr
- per HOUR!
- (divide by 0.5 for AGs)
AG patient monitoring
- peak: 30 minutes post 30 minute infusion
- trough: 30 minutes immediated pre-dose
why extended interval dosing (EI)?
- concentration depended killer
- post-antibiotic effect
- increased efficacy
- less toxicity
- minimize antimicrobial resistance
- convenience
- less costly
use caution or avoid extended interval dosing in
- enterococcal endocardiitis
- burns
- renal failure
- osteomyelitis
- meningitis
- pregnancy/CF/ febrile neutropenia
gentamicin & tobramycin EXTENDED interval dosing
- 7mg/kg (actual body weight)
- CrCl:
- > 60: 24 hrs
- 40-59: 36hrs
- 20-39: 48hrs
vanc spectrum of activity
- gram +
- MRSA/ resistance strep/ beta lactam allergies
vanc ototoxicity is related to
high peaks
vanc nephrotoxicity is related to
prolonged high troughs
vanc goal peak
30-40mg/L
vanc goal trough
- 15-20mg/L: bacteremia, meniningitis, pneumonia, SSTI, MRSA, endocarditis, osteomyelitis
- 10-15mg/L: everything else
which weight do you use for vanc dosing?
actual body weight
typically adult vanc starting dose
15-20mg/kg
- 2g/dose limit
- Q8 or Q12H frequency
- loading dose in erious infections: 25-30mg/kg over 1.5-2hours
vanc infusion rate
1g/hour
- 1 hour infusion rates
if vanc trough is high
- increase interval (decrease frequency)
- decrease dose proportionally
if vanc trough is low
- decrease interval (increase freq)
- increase dose proportionally
vanc pediatric dosing
15mg/kg Q6H
vanc peak monitoring
1 hour after infusion is done
- dont really get peaks though in peds
when to draw serum concentrations of vanc
- convention with 4th dose (sometimes 3rd)
in whom to draw serum concentrations with vanc
- aggressive doses (15-20mg/L troughs)
- critically ill
- changing renal function
- concomitant nephrotoxic agents
- prolonged therapy
follow up serum concentrations with vanc
- at least weekly in stable pts
- monitor SCr 3xwk
- peak monitoring not recommended
intermittent HD with vanc
- 20mg/kg LD prior to 1st session
- 10mg/kg
- Serum concentration 4 hours post 2nd session
vanc toxicity
- infusion related (Redman’s syndrome)
- not allergy
- decrease infusion rate
lanoxin generic
digoxin
digoxin indication
- HF (HFrEF)
- Afib
MOA of digoxin in HF
inhibition of Na/K/ATPase-> increased myocardial contractility
MOA of digoxin in Afib
reduction of electrical impulses in the AV node & decreased HR
digoxin effects on the heart
- negative chronotropic (rate)
- positive ionotropic (contraction)
PK for digoxin
- linear at steady state
factors to consider in digoxin dosing & monitoring
- renal function
2, electrolytes (hypo-K & Mg-> enhance toxicity) - thyroid disease (hypo-[high]; hyper [low]
- med review for interactions
labs to check before digoxin use
Scr
TSH
K+
Mg+
pediatic digoxin dosing is
weight based
- younger the pt, higher the dose
when do you use a loading dose for digoxin?
- Afib pts
- NOT HF
digoxin loading dose
- give 50% initially
- 2 additional doses 25% each
- all separated by 6 hours eah
- monitor HR & EKG
target concentrations of digoxin
- narrow therapeutic drug
- HF: 0.5-0.9mcg/L
- Afib: 1-1.5mcg/L
indications for digoxin level measurement
- alterations in renal function
- suspect toxicity
- diagnosed with interacting disease state
- drug-drug interaction
- to assess compliance
when to obtain digoxin drug concentrations
- loading dose: 12-24 hrs after last dose
- maintenance: 5-7days after initiation (trough 12-24hr after last dose)
- ESRD take longer to SS
- exercise may falsely lower trough
toxic digoxin levels
> 2mcg/L
signs and symptoms of digoxin toxicity
- CNS: visual disturbances, HA, confusion, fatigue, dizziness
- GI: N/V/D, abd pain, anorexia
- *CV: bradycardia, AV block, vent. arrhythmias
if digoxin toxicity occurs
- stop digoxin
- monitor daily until
what is digibind
- digoxin immune fab
- used to counteract digoxin toxicity
cardiac drips are used for
- vasopressors
- ionotropes
- anti-hypertensives
most B1 to most Alpha vasoactive activity
isoproterenol dobutamine dopamine E(B>A) NE(A>B) phenylephrine
low dose DA
- primarily on DA receptor
- works on urine output
- 1-3 makes you pee
intermediate dose DA
4-10 makes your heart beat again
high dose DA
more vasoconstriction
>10
vasopressin MOA
- vasoconstriction via activity at V1 on smooth muscles
- 0.3u/min
- titrated off last when d/c other vasopressors
vasopressor selection in adult pts
- 1st line: NE
- 2nd line: E
- failure w/ other agents: DA
goals of vasopressive therapy
- increase BP & perfuse organs
- titrate to desired effect
- CVP 8-12
- MAP>65
- O2 sat >70%
MAP=
1/3SBP+2/3DBP
or
DBP+0.33pulse pressure
prevent extravasation with vasopressors adverse events by ensuring
central line is in place
if extravasation does occur with vasopressors
- tapper off
- give nitrobid ointment or phentolamine
ionotrophs
dobutamine (dobutrex)
milrinone (primacor)
target cardiac index with ionotrophs
> 2.2
vasodilators
nitroglycerin
nitroprusside (nitropress)
what drug had an ADE of methemoglobuinemia?
IV nitroglycerine
nitroprusside ADE
cyanide toxicity
IV antihypertensives
nicardipine (Cardene)
labetalol (trandate)
