Pharmacology

Question 1

What is the recommended maximum safe dose for plain
lidocaine?

And with adrenaline?

Answer 1

3mg/kg
7mg/kg
per KG bodyweight

Question 2

Components of Moffett’s solution

Answer 2

Cocaine,
adrenaline,
Normal saline,
and sodium bicarbonate in some (to free base the cocaine and make it more lipophilic, pKa 8.6).

Question 3

Side effects pf Moffett’s solution (6)

Answer 3

Tachycardia
Arrhythmias
Hypertension, Hyperthermia
Sweating
Anxiety.

Question 4

What typw of anesthetic is Lidocaine and how does it work?

Answer 4

Lidocaine is an amide local anaesthetic by acting on the sodium channels (blocks them) cause a reversible conduction block along nerves

Question 5

How many mg of lidocaine is in 1ml of 1% lidocaine?

Answer 5

10mg /ml

1000mg = 1 g
1% = 1g / 100ml

Question 6

When would you use (Co-Phenylcaine Spray) lidocaine and phenylephrine spray on the nose?

Answer 6

Decongest the nose prior to nasal surgery
Anaesthetise and decongest the nose prior to flexible nasendoscopy
Decongest prior to cautery in epistaxis

Question 7

What would you use (exactly) to numb the nose prior to cautery?

Answer 7

Co-Phenylcaine Spray: lidocaine 5% and phenylephrine 0.5% spray

Question 8

Local doses:

Cocaine
Lidocaine
Lidocaine + adrenaline
Levobupivaine (and it’s other name)

Answer 8

Cocaine – 3mg/kg
Lidocaine ( Plain) – 3mg/kg
Lidocaine ( with Adrenaline)- 7mg/kg
Levobupivacaine (Chirocaine)- 2mg/kg

Question 9

Pharmacology of phenylephrine, adrenaline and xylometolazin:

Answer 9

Alpha 1-adrenoreceptor agonist causing vasoconstriction

(sympathmomimetics)

Question 10

Bupivacaine
Levobupivacaine
Lidocaine
Benzocaine
Chloroprocaine
Cocaine
Prilocaine

Which types of LA are each of them?

Answer 10

Am’I’de all contain an ‘I’ before the ‘caine’ somewhere:

Bupivacaine - Amide
Levobupivacaine - Amide
Lidocaine - Amide

No I before the caine

Benzocaine - Ester
Chloroprocaine - Ester
Cocaine - Ester
Prilocaine - Ester

Question 11

How do local anaesthetics work?

Answer 11

Suppress action potentials in excitable tissues by blocking voltage-gated Na+ channels. In doing so, they inhibit action potentials in nociceptive fibres and so block the transmission of pain impulses.

Question 12

Patient is allergic to lidocaine, which type of anaesthetic could you use instead and why?

Answer 12

Lidocaine = amide, pt therefore likely allergic to amide types.

Could try an Ester e.g. cocaine, prilocaine, benzocaine etc.

Question 13

Which type of LA are patients more likely to be allergic / hyprsensitive to?

Answer 13

Hypersensitivty more common with Esters

Question 14

Naseptin cream ingredients

Answer 14

chlorhexidine dihydrochloride 0.1%
neomycin sulfate 0.5%

Question 15

What causes allergic reactions in Naseptin

Answer 15

Peanut AND SOY
( because there is crossover between peanut and soya allergy)

Question 16

Alternative to Naseptin cream (if pt has allergies - to what?)

Answer 16

Bactroban
(Mupirocin 2%)

(Peanut and soya - because there is crossover between peanut and soya allergy)

Question 17

Chlorphenamine mechanism action

Answer 17

H1- histamine blocker

Question 18

Chlorphenamine side effects

Answer 18

Drowsiness
Dry mouth
Dry eyes
Blurred vision

Question 19

Examples of sialogogues:

Answer 19

Non drug:
- Lemon / lemon sweets
- Chewing gum

Drugs:
- Pilocarpine (cholinergic drugs / muscarinic / parasympathtic receptor agonists)