Anesthesia Pharmacology: Sedative-Hypnotic Drug Practice
Questions
Benzodiazepine pharmacology is most closely linked to which neurotransmitter system?
noradrenergic
GABA system
cholinergic
glycine system
Anxiolytic drug acting through serotonin receptors:
diazepam (Valium)
buspirone (BuSpar)
triazolam (Halcion)
phenobarbital
A comatose patient is brought to the emergency department with severe respiratory depression caused by diazepam overdosage. Reasonable intervention at this point include:
administer naloxone (Narcan) to block the drug's effect at the receptor
provide supportive therapy until the drug effect wears off.
administer flumazenil
B & C
A chronic alcohol and diazepam abuser is hospitalized for management of withdrawal symptoms. Buspirone, an anxiolytic, is administered to alleviate withdrawal, but the symptoms continue and worsen. Why?
Buspirone (BuSpar) dosage too low.
Buspirone (BuSpar) does not exhibit cross-tolerance with sedative-hypnotic/benzodiazepines.
Management of alcohol or benzodiazepine withdrawal must be managed with a stronger drug, such as haloperidol.
Buspirone (BuSpar) is too rapidly inactivated (first-pass effect) to be useful in managing withdrawal.
Short-acting benzodiazepine
diazepam (Valium)
flurazepam (Dalmane)
triazolam (Halcion)
buspirone (BuSpar)
Benzodiazepine most appropriate in patients with impaired hepatic function:
Lorazepam (Ativan) because of first-pass effects and because it lacks long-acting metabolites.
Oxazepam (Serax) since it has no long-acting metabolites and is conjugated to an inactive glucuronide directly.
Buspirone (BuSpar) since it has limited abuse potential
Anxiolytic effects
diazepam (Valium)
clonidine (Catapres)
both
neither
i.v. anesthetic used for induction.
methohexital (Brevital)
thiopental (Pentothal)
both
neither
Ion channel that contains the GABA receptor:
sodium
calcium
chloride
potassium
Zolpidem (Ambien):
antagonized by flumazenil (Romazicon)
muscle relaxation
minimal hypnotic properties
Long duration of action
Pharmacological basis for prescribing benzodiazepines for anxiety:
Low risk of drug interactions based on hepatic enzyme induction
high therapeutic index
availability of flumazenil (Romazicon) to manage overdosage
all of the above
Therapeutic disadvantage(s) of benzodiazepines:
Amestic effects
High cost
Psychologic dependencies
all of the above
Antianxiety drug(s)
propranolol (Inderal)
buspirone (BuSpar)
phenobarbital (Luminal)
all of the above
May be especially effective in treating anxiety associated with nicotine withdrawal:
meprobamate
clonidine (Catapres)
both
neither
Most useful in reversing symptoms of benzodiazepine overdosage:
amphetamine
buspirone (BuSpar)
flumazenil (Romazicon)
naltrexone (ReVia)
Skeletal muscle spasticity of CNS origin:
flumazenil (Romazicon)
diazepam (Valium)
Contraindicated in patients with a history of acute intermittent porphyria: