Benzos for Bozos Flashcards
Three most commonly used benzos in our practice?
Midazolam (Versed), Lorazepam (Ativan), and Diazepam (Valium)
Order of potency of top 3 benzos?
Lorazepam > Midazolam > Diazepam
What determines potency of benzos?
Receptor binding affinity (all are highly lipophilic and protein-bound)
General chemical structure of benzos?
Benzene ring fused to 7-member diazepine ring, 2 Ns @ 1 & 4, phenyl @ 5
On which receptors do benzos work?
GABA receptor complex (alpha subunits); allows Cl- to pass inside neuron, making cell more negative, decreasing response (inhibitory) to other neurotransmitters.
Do benzos produce amnesia?
Yes, yes they do. They produce anterograde amnesia.
What do you know about the amnesia produced by benzos?
Doesn’t affect previously formed memories; does not affect short-term memory, but memories are likely are not transferred to long-term memory. Memory impairment may be more pronounced in IV administration, high dose, slow elim., and accumulation of drug.
Does the high protein-binding of benzos affect distribution and effect?
Yes. Hypoalbuminemia leads to increased levels of free drug in the plasma, leading to greater distribution and effect.
Desired effects of benzos:
Anterograde amnesia
Sedation/hypnotic
Anxiolytic
Anticonvulsant
Skeletal muscle relaxant
Side effects of benzos that are not necessarily desired:
Decr. CMRO2 and CBF
Do not increase or decrease ICP
Minimal depression of ventilation
How do elderly folks do with benzos?
They are more sensitive.
Benzos have _______ effects with other drugs like opioids and propofol.
synergistic
What are indications for benzos?
Sedation
Anesthesia induction
Anesthesia maintenance
Anticonvulsant
Benzos metabolized:
In the liver (1st order kinetics):
-Midaz: CYP450 3A4 (phase I)
- Diaz: N-demthylation (phase I)
- Loraz: glucuronic acid conjugation (phase II)
Benzos _____ MAC of VAAs.
decrease (by 30%)
