Local Anaesthetic

Question 1

What is the negative effect of local anaesthetic?

Answer 1

It causes Vasodilation so can cause haemorrhage at the site of administration

Question 2

How is the vasodilating effect of local anaesthetic counteracted?

Answer 2

Adrenaline is combined with the local anaesthetic which causes a vasoconstriction effect so counteracts the vasodilating effect from the local

Question 3

What is the negative effect of using adrenaline in local anaesthetic?

Answer 3

The use of adrenaline in poorly perfumed tissues can result in ischaemia

Question 4

What depth of anaesthesia is achieved with topical local anaesthetic?

Answer 4

1-2mm

Question 5

How is intradermal local anaesthetic administered?

Answer 5

Injections in a ring to creature a desensitise weal in the skin

Question 6

What is intra-articular/intra-synovial anaesthetic?

Answer 6

Local anaesthetic injected into a joint/synovial joint

Question 7

What is intra-pleural anaesthetic?

Answer 7

Local anaesthetic administered via a chest tube

Question 8

What is infiltration analgesia?

Answer 8

Direct infiltration into tissues to affect local nerve endings e.g wounds

Question 9

How should infiltration analgesia diluted?

Answer 9

With 0.9% saline - NOT sterile water

Question 10

Where should Infiltration analgesia not be used?

Answer 10

Where an end arterial supply exists (e.g tail/ear due to risk of necrosis

Question 11

Why should infiltration analgesia not be used by an end arterial supply?

Answer 11

Risk of necrosis

Question 12

What is regional analgesia?

Answer 12

A Blockade of specific sensory nerves e.g distal limb nerve blocks

Question 13

What care needs to be taken with regional analgesia?

Answer 13

Avoid blockade of motor nerves as this can cause poor recovery

Question 14

What can be used to locate nerves for regional analgesia?

Answer 14

Handheld nerve stimulator

Question 15

What is Regional peri-neural anaesthetic?

Answer 15

Injection of local anaesthetic agent around nerve trunks

Question 16

What are examples of Regional peri-neural anaesthetics?

Answer 16

Intercostal block,
maxillary and mandibular blocks,
Inferior alveolar nerve to desensitise the rostral mandible for fracture repairs

Question 17

How is regional intravenous analgesia used?

Answer 17

The limb is firstly exsanguinated with the application of an Esmarch bandage, then a tourniquet is placed around a limb and local anaesthetic agent is intravenously injected distal to the tourniquet providing analgesia that lasts until the tourniquet is removed

Question 18

What is Spinal Analgesia?

Answer 18

Injection of local anaesthetic into the spinal canal (e.g epidural)

Question 19

Where is the needle inserted for spinal analgesia?

Answer 19

Between L7 and S1

Question 20

What is a field block?

Answer 20

Infiltration of local anaesthetic agent far away from the set of surgery to produce effective analgesia without compromising wound healing