LA Flashcards
Local anaesthetic agents
a. lignocaine blocks the sensation of pain before motor function
a) True, type C fibres are blocked before motor functions
Local anaesthetic agents
b. ropivacaine inhibits A-fibres before C-fibres
b) False, type C fibres are blocked before motor functions
Local anaesthetic agents
c. tetracaine is an ester local anaesthetic
c) True
Local anaesthetic agents
d. the unionised form of lignocaine diffuses into the axon membrane
d) True, unionized LA diffuses to the target where it is ionized
Local anaesthetic agents
e. lignocaine is metabolised to para-aminobenzoic acid
e) False, esters are metabolized by plasma cholinesterases into para-aminobenzoic acid. Lignocaine is an amide
Local anaesthetic agents
a. lignocaine blocks the sensation of pressure before pain
A. False, the sensation of pain is blocked first
Local anaesthetic agents
b. ropivacaine inhibits C-fibres before A-fibres
B. True, c-fibres are inhibited first
Local anaesthetic agents
c. procaine is an ester local anaesthetic
C. True, procaine is a local anesthetic of the ester type that has a slow onset and a short duration of action.
Local anaesthetic agents
d. the ionised form of bupivacaine diffuses into the axon membrane
D. False, the unionized form of the LA diffuses into the axon membrane
Local anaesthetic agents
e. tetracaine is metabolised by pseudocholinesterase
E. True, esters are metabolized by plasma cholinestares
Local anaesthetic agents
a. the ionised form of lignocaine is more lipophilic than the non-ionised form
A. False, unionized lignocaine is more lipophilic
Local anaesthetic agents
b. bupivacaine has a shorter duration of action than procaine
B. False, bupivacaine has a longer DOA
Local anaesthetic agents
c. ropivacaine is less cardiotoxic than bupivacaine
C. True, bupivacaine causes ventricular fibrillation
Local anaesthetic agents
d. procaine is metabolised by plasma cholinesterase
D. True, esters are metabolized by plasma cholinesterases
Local anaesthetic agents
e. adrenaline decreases the duration of action of lignocaine
E. False, adrenaline localizes the action of lignocaine, thereby extending its DOA
Local anaesthetics
a. lignocaine is metabolised by plasma cholinesterase
a. False, amides are metabolized by the liver
Local anaesthetics
b. bupivacaine is more cardiotoxic than lignocaine
b. True, causes ventricular fibrillation
Local anaesthetics
c. procaine has a longer duration of action than lignocaine
c. False, procaine is very short acting
Local anaesthetics
d. the non-ionised form of lignocaine inhibits passage of sodium through the neuronal cell
d. False, ionized lignocaine exhibits its effect
Local anaesthetics
e. lignocaine crosses the blood brain barrier
e. True, crosses the BBB and the placenta
Local anaesthetics
a. the unionized form of lignocaine crosses the neuronal membrane
a. True
Local anaesthetics
b. procaine causes allergic dermatitis
b. True, procaine causes allergic dermatitis
Local anaesthetics
c. bupivacaine is metabolised by plasma cholinesterase
c. False, bupivacaine is an amide and is thus metabolized by the liver
Local anaesthetics
d. adrenaline shortens the duration of action of lignocaine
d. False, adrenaline prolongs the effects of lignocaine
Local anaesthetics
e ropivacaine has a shorter half- life than procaine
e. False, procaine has a shorter half life than ropivacaine
Lignocaine
a. undergoes hepatic metabolism
a. True, amides are metabolized in the liver
Lignocaine
b. is more lipophilic than articaine
b. False, articaine has a thiophene ring which makes it more lipophilic
Lignocaine
c. blocks the sensation of pain before motor function
c. True, blocks C fibres before A fibres
Lignocaine
d. is more cardiotoxic than bupivicaine
d. False, bupivacaine is the most cardiotoxic
Lignocaine
e. blocks C-fibres before A-fibres
e. True blocks C fibres before A fibres
Local Anaesthetic – Bupivacaine
a. in the ionised form crosses the neuronal membrane
a. False, unionized
Local Anaesthetic – Bupivacaine
b. is used for epidural infusion for postoperative pain control
b. True
Local Anaesthetic – Bupivacaine
c. is more cardio toxic than lignocaine
c. True
Local Anaesthetic – Bupivacaine
d. has a shorter duration of action than articaine
d. False
Local Anaesthetic – Bupivacaine
e. reduced doses are indicated in hepatic disease
e. True, amides are metabolised by the liver
A 55 year-old male requires stitches after an injury. He requires a short-acting local anaesthetic. He has a plasma cholinesterase deficiency. Which agent from the list above is commonly used for this purpose? 1. Articaine 2. Bupivacaine 3. Levobupicaine 4. Lignocaine 5. Procaine 6. Ropivacaine
Lignocaine
