Anaesthetic Drugs Flashcards
What is the triad of anaesthesia?
- triad of what anaesthetist aim to achieve during major surgery
What are the 3 parts of the triad of anaesthesia used during major surgery?
1 - analgesia, amnesia and low HR
2 - amnesia, low HR and muscle relaxation
3 - analgesia, low HR and muscle relaxation
4 - muscle relaxation, analgesia and amnesia
4 - muscle relaxation, analgesia and amnesia
What are some of the roles an anaesthetist performs during the day?
- pre-assessment prior to surgery
- anaesthetise
- monitor recovery
post-operative visits
Do all drugs used in anaesthesia target the same places in the body?
- no
What are some of the sites in the CNS where analgesic drugs target?
- thalamus
- cerebral cortex
- reticular activating system
- spinal cord
What are some of the receptors involved in analgesic drugs?
- GABA and glutamate receptors
- voltage gated ion channels
- glycine and serotonin receptors
What are analgesic agents able to do excitable tissues?
- suppress excitable tissues
- important for all 3 aspects of the triad of anaesthesia
- especially consciousness
Analgesic agents possess an important feature which allows them to move freely in different compartments of the body, especially crossing the blood brain barrier (BBB). What is the property that they possess that allows them to cross the BBB?
1 - steroid like structure
2 - bind with CO2 and cross BBB
3 - lipid soluble
3 - lipid soluble
- meaning they can cross lipid membranes
There are 2 general delivery methods anaesthetist use, what are they?
1 - inhaled
2 - intravenous
What are the 3 common inhaled analgesic drugs used today?
1 - sevoflurane
2 - isoflurane
3 - desflurane
What is the core intravenous analgesic drug that we need to know?
1 - propofol
2 - thiopentone
3 - etomidate
4 - ketamine
1 - propofol
What is the main action of gamma-Aminobutyric acid also known as γ-aminobutyric acid, but referred to as GABA?
- opens Cl- channels, increasing negative charge in a cell
- reduces chance of an action potential
What is the mechanism of action of propofol that is most commonly described?
1 - inhibits GABA
2 - inhibits serotonin receptors
3 - potentiates GABA
4 - potentiates serotonin
3 - potentiates GABA
- binds to GABA-A receptor
- essentially increases the inhibition of neurotransmitters
Once propofol is administered intravenously does it become bound (to proteins so it remains in the bloodstream) or unbound so it can be absorbed by cells?
- both
- bound means it acts as a reserve (most of it)
- unbound is active
- lipid soluble so can move anywhere in the body, including crossing the blood brain barrier
As propofol is administered intravenously it has 100% bioavailability, which means it peaks in the blood very quickly. When it is administered it enters the venous system. To enter the circulation it must travel to which organ?
1 - heart
2 - lungs
3 - liver
4 - kidneys
1 - heart
- returns to right side of the heart
- travels to the lungs
- back to left side of the heart
- enters systemic circulation