Local anaesthetics Flashcards
Where do local anaesthetics (LA) work?
The axon hillock and nodes of Ranvier
What specifically is the mechanism of action of LAs?
Reversibly block the generation and conduction of action potentials
Which chemical feature is associated with short acting and long acting LAs?
Short acting - esters
Long acting - amides
Why are there two different lengths of action?
Esters are metabolised by esterases in the plasma
Amides are metabolised in the liver
Name and example of a short acting and long acting LA
Short acting - cocaine, procaine, tetracaine
Long acting - lidocaine, bupivacaine
What is use dependence?
The more the sodium channel is being used the more effective the LA due to there being more access to binding site
What are the SIX routes of LA administration?
Surface Infiltration Nerve block Spinal Epidural Intravenous
