Local Anaesthetics Flashcards Preview

A - MSRA Drugs [4] > Local Anaesthetics > Flashcards

Flashcards in Local Anaesthetics Deck (18)
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1
Q

Give 2 examples of local anaesthetics

A
  • Lidocaine (also known as lignocaine)

- Bupivacaine

2
Q

What is the mechanism of action of local anaesthetics?

A
  • Reversibly blocks Na channels to prevent neurotransmission

- Causes vasodilatation of arteries

3
Q

What might the addition of adrenaline to local anaesthetics do?

A

Prolong anaesthetic effects (as it is a vasoconstrictor)

idgi

4
Q

What do you need to be careful of not doing when injecting local anaesthetic?

A

Injecting LA mixed with adrenaline into organs with end-artery blood supply

5
Q

What is the route of delivery of local anaesthetic?

A
  • Topical
  • IV
  • Epidural
6
Q

How should the dose of local anaesthetic ideally be calculated?

A

For non-emergency indications, using ideal body weight

7
Q

What may be used when local anaesthetic is used topically?

A

Occlusive dressing

8
Q

What are the indications for local anaesthetics?

A
  • Local anaesthetic for procedures
  • Treatment and prevention of ventricular tachycardia and ventricular fibrillation post-MI
  • Surface and infiltration anaesthesia, nerve blocks, and epidural blocks
9
Q

When are local anaesthetics contraindicated?

A
  • Severe myocardial depression
  • Sinoatrial disorders
  • AV block
10
Q

When should lidocaine be avoided?

A

Pregnancy

11
Q

Why should lidocaine be avoided in pregnancy?

A

Cause neonatal bradycardia, and, following large doses, respiratory and CNS depression

12
Q

What should be done when local anaesthetic is given in low cardiac output states?

A

Dose reduction

13
Q

How can it be ensured local anaesthetic is effective?

A

Sensation can be tested by touching the area where the local anaesthetic has been used with the needle tip and asking the patient if the area feels numb or sharp

14
Q

What might interact with local anaesthetics?

A

Adrenaline

15
Q

What might happen if local anaesthetics are given with adrenaline?

A

Prolongs anaesthetic effects - but this is usually good so pretty nothing interaction lol

16
Q

What are the common side effects of local anaesthetics?

A
  • Bradycardia
  • Hypotension
  • Confusion
  • Convulsions
  • Dizziness
  • Drowsiness
  • Respiratory depression
17
Q

What are the rare side effects of local anaesthetics?

A

Cardiac arrest in overdose

18
Q

What should the patient be told about regarding the effect of local anaesthetic?

A

The local anaesthetic will cause temporary loss of sensation to the affected area. The patient may feel some stinging, but this should not hurt and if the patient feels pain at any time during the procedure they should inform the HCP performing the procedure