General anaesthetics second half 1.0 Flashcards
2 main types of administering GAs?
Inhalation and intravenous
Best aspect of inhaled GAs?
V controllable as the dose in the air is v quickly transferred
Main types of inhaled GAs?
Halogenated ethers, halogenated hydrocarbons
Halogenated hydrocarbon example?
Halothane, isofluorane
Advantages of halothane and isoflurane?
V potent and stable
Main pro of intravenous GAs?
V rapid
Which type of general anaesthetic is used for induction of GA?
Intravenous
Which type of anaesthetic is used for maintenance of GA?
Inhaled
Major surgery general anaesthetic order?
Benzodiazepine, then intravenous (thiopental), then inhaled (halothane)
Rapid unconsciousness anaesthetic?
thiopental (short acting)
Inhaled general anaesthetics to maintain GA?
N2O, halothane, sevofluorane
When are analgesic drugs used?
post operative care
What is fentanyl used for?
analgesic effect after surgery when the general anaesthetic has worn off
Which compounds are used for paralysis of skeletal muscle?
Suxamethonium
How does Suxamethonium work?
It is a nicotinic ACh receptor antagonist
What drugs are people given pre-op?
Benzodiazepines, midazolam
Examples of inhaled anaesthetics?
N2O, halothane, enflurane, isoflurane, desflurane, sevoflurane
Side effect of halothane?
Toxic to liver
Which inhaled GA is used more in veterinary than human surgery?
Halothane
Why is sevoflurane used the most?
Has the least side effects
Types of intravenous GAs?
Thiopental, etomidate, propofol, ketamine, benzodiazepines
Most widely used intravenous GA?
propofol
Mechanism of local anaesthetics?
Voltage-gated sodium channel block
Two main theories of how GAs work?
lipid theory, and protein theory
Lipid theory of GAs?
good GAs are more lipophilic (can soak into lipids) and so soak into the lipid bilayer and block membrane spanning proteins (Na+ channels in neurons etc)
Protein theory of GAs?
More potent a GA is, less of it is needed to inhibit luciferase proteina action, so GAs might generally inhibit protein action
What type of proteins do GAs target?
Transmitter receptors, ion channels, transporters and release
What do GAs do regarding inhibitory receptors?
Potentiate them, meaning they are stronger (more hyperpolarisation)
What do GAs to to excitatory receptors?
Block them
How do GAs affect ion channels?
They reduce the frequency of them opening