Inhaled anesthetics 2: pharmacodynamics 2 Flashcards
Modern theory of anesthetic action suggests inhaled anesthetics: (select 2)
a. interact with stereoselective receptors
b. stimulate the NMDA receptor
c. Produce immobility by binding in the dorsal horn of the spinal cord
d. facilitate GABA transmission
A. interact with stereoselective receptors
d. facilitate GABA transmission
The primary target of halogenated anesthetics in the brain is
the facilitation of the GABA-A receptor
The primary target of volatile anesthetics in the spinal cord is
stimulation of glycine channels and inhibition of NMDA receptors and sodium channels
Volatile anesthetics produce immobility in the ______ horn of the spinal cord.
ventral
As a general rule, volatile anesthetics either
stimulate inhibitory receptors or inhibit stimulatory receptors
The gaseous anesthetics (nitrous oxide and xenon) target
the NMDA receptor (antagonism) and the potassium 2P-channel (stimulation)
What inhibitory pathways do volatile anesthetics stimulate?
GABA-A receptor
potassium channels
Glycine channels
What stimulatory pathways do volatile anesthetics inhibit?
NMDA
nicotinic
sodium channels
dendritic spine function and motility
How do volatile anesthetics produce amnesia?
amygdala & hippocampus
Autonomic effects of volatile anesthetics are produced in the
pons & medulla
Analgesia is produced in the
spinothalamic tract
Immobility is produced in the
ventral horn of the spinal cord
Volatile anesthetics produce unconsciousness by interacting in the
cerebral cortex, thalamus, and reticular activating system
Regarding the modern halogenated anesthetics in the adult at 1 MAC:
a. QT interval increases
b. Heart rate decreases
c. systemic vascular resistance increases
d. mean arterial blood pressure increases
a. QT interval increases
Nitrous oxide __________MAP and ______________SVR by ____________
increases MAP & SVR by SNS activation
Current thinking disputes the theory of _______ steal. Volatile anesthetics precondition
coronary steal. precondition the myocardium and protect it against ischemia
Halogenated anesthetics ___ MAP in
reduce MAP in a dose-dependent fashion
(at equivalent doses, there’s little difference between agents)
Which halogenated agents increase heart rate?
isoflurane & desflurane (sevoflurane does not)
Which agent reduces SVR the least?
Sevoflurane
Halogenated decrease __________ in a dose-dependent fashion.
contractility & SVR