Flashcards in General Anesthetics Deck (22)
How do anesthetics work?
GABAa chloride channel IPSP
GABA stimulates chloride channel to open making cell hyperpolarized (inhibiting APs)
What is MAC?
minimal alveolar concentration at 1ATM that prevents movement during skin incision in 50%
What is the MAC formula to achieve preventing movement in 95% people?
1.3 x MAC
What 3 factors influence MAC?
What 4 factors do NOT influence MAC?
As cardiac output increases, what happens to induction with inhalation anesthetics?
(inverse relationship with CO)
What is the equation for anesthesia?
True or false: the faster the agent gets from one compartment to the next, the slower it reaches equilibrium
What 3 factors determine GA uptake from the blood?
2) partial pressure difference
3) cardiac output
the end tidal partial pressure is the brain partial pressure
Which drug is more soluble in the blood, NO or Halothane?
Which achieves equilibrium faster, NO or halothane?
NO (blood cannot hold that much NO)
Which blood compartment is larger, NO or halothane?
halothane (holds more since drug is more soluble)
What does a larger blood/gas partition coefficient mean?
takes longer to reach equilibrium
larger blood compartment
What are the vessel rich organs? BHLK
Increased blood flow near alveolus _______ (slows/speeds up) equilibrium because it increases uptake
remember: cerebral blood flow is regulated so an increase in CO should not bring extra agent to brain
What effect does GA have on lungs?
What happens to the brain during GA?
(increased blood flow but decreased O2 consumption)
What IV anesthetic is used for induction, maintenance, sedation in the OR or ICU?
increases intracranial pressure
What was the most used induction agent before propofol?
What are some of the good effects of ketamine?
1) dissociative anesthesia
2) bronchodilator, keep breathing
3) increase BP and HR
4) increase ICP and cerebral blood flow