General anesthesia Flashcards
Ketamine produces what effect?
Dissociative anesthesia
What is MAC?
Stands for minimum alveolar concentration (alveolar-lungs). This is concentration at which 50% of people don’t respond to a surgical stimulus- IE the concentration at which the gas works for half of the population.
What are the goals of general anesthesia?
To produce a state of unconsciousness, unresponsiveness, amnesia, immobility (is this talking about the white house?) and autonomic stability in the anesthetic state.
T/F Modern general anesthesia tends toward using a combination of drugs, taking advantage of the best aspects of each.
True
What would be some characteristics of an ideal surgical anesthetic treatment?
A smooth and rapid induction- they go under quick
Once they’re under, they’re unconscious and don’t remember the surgery.
Essential physiological functions are maintained while undesired reflexes are blocked
The skeletal muscles are relaxed (so they’re not flailing all over the place) but the respiratory muscles are still working as they should
The perception of sensory stimuli should be blocked and when you stop administering the drug, the patient comes out of it smoothly, quickly, and with no lasting effects.
There are a lot of things that we want to have happen in the ideal surgical anesthetic treatment. Can it all be done with one drug? What are some things we use to get the job done?
It can’t be done with just one drug.
We use antimuscarinics to minimize salivation and to block vagal stimulation
We use analgesics for preoperative pain relief, sedation and amnesia
We use NO or opioids to reduce the anesthetic requirement and/or provide analgesia
Anti-nicotinic’s are used to paralyze skeletal muscle
For us dentists, do we want to put someone under all the way? Why or why not?
Not really- most of what we do doesn’t warrant general anesthesia.
What is the Meyer-Overtone correlation?
These two dudes noted a very strong correlation between solubility in olive oil and anesthetic potency.
At what point does anesthesia begin?
It begins when the anesthesia reaches a critical concentration in membrane lipids.
Why is general anesthesia dependent on the concentration of the drug the membrane lipids?
If the drug is in the membrane lipids then the drug can act on membrane proteins.
What membrane proteins are likely targets of general anesthetics? Why?
Ligand activated ion channels
If you block the influx or efflux of ions you can depolarize or hyper polarize cells so that action potentials occur or do not occur.
Why would GABA receptors be an attractive target for general anesthetics?
GABA receptors are also found in the membrane, but they are found in the brain.
GABA is an inhibitory neurotransmitter. GABA lets Cl- in and this hyper polarizes the membrane. Barbiturates can bind the GABA receptors and activate the inhibitory effects of GABA. It’s like super inhibition now.
Which is more sensitive to anesthetics- synaptic transmission or actions potentials? Why?
synaptic transmissions
Effects have have been observed at both the pre and post synaptic terminals
The thalamocortical loop and the reticular activating formation are thought to be critical for maintaining consciousness.
Cool fact Jordan.
The limbic system is involved in memory. Inhibition of this system is likely to be involved in anesthetic induced amnesia.
Yet another cool fact.