LOCAL ANAESTHETIC OSCE

Question 1

how do local anaesthetics work?

Answer 1

LA stops nerve conduction by blocking the voltage gated sodium channels

Question 2

what can local anaesthetic molecules cause in the body?

Answer 2

badycardia and hypotension

Question 3

what are some examples of ester LAs?

Answer 3

benzocaine

Question 4

what are some examples of amide LAs?

Answer 4

• lignocaine
• prilocaine
• articaine
• bupivicaine

Question 5

are LAs vasodilators or vasoconstrictors?

Answer 5

vasodilators

Question 6

what other substances are usually found in LA solutions? give examples?

Answer 6

vasoconstrictors

• adrenaline
• felypressin

Question 7

what are the Lignocaine preparations for dental injections?

Answer 7

• 2% lignocaine HCL

- 2% lignocaine HCL + 1:80000 adrenaline

Question 8

what are the typical prilocaine preparations for dental injections?

Answer 8

• 4% prilocaine HCL

- 3% prilocaine HCL + felypressin (0.03U/ml)

Question 9

who is felypressin not suitable for?

Answer 9

pregnant women (may infuce labour)

Question 10

what are the two types of LA administrative techniques used in dentistry?

Answer 10

• inflitration

- block

Question 11

how can the deposition of the local anaesthetic be desribed in the infiltration technique ?

Answer 11

LA solution deposited around terminal branches of nerves

Question 12

how can the deposition of the local anaethstic be described in block techniques?

Answer 12

LA solution desposited around the nerve trunk

Question 13

if you are restoring a tooth, what tissues should be anaesthetised?

Answer 13

• dental pulp

- soft tissues

Question 14

if you are providing anaesthesia to the maxillary teeth dental pulp, what LA technique would be used?

Answer 14

buccal infiltration

Question 15

if you are aiming to anaesthetise the maxillary teeth buccal ginigivae, what LA technique would be used?

Answer 15

buccal infiltration

Question 16

if you are aiming to anaesthetise the maxillary palatal gingivae of a tooth, what LA technique would be used?

Answer 16

palatal injection

Question 17

when would a mandibular dental block injection be used? (IDB/IAN)

Answer 17

to anaesthetise the pulp of the lower molars and second premolar

Question 18

when would a mental nerve block techique be used?

Answer 18

when providing dental pulp anaesthetic to the lower premolars and canine

Question 19

what LA technique is used to provide anaesthesia to the lower canine and insisors pulp?

Answer 19

buccal/labial infiltration

Question 20

when providing anaesthesia to the buccal gingivae of the lower molars & second premolar, what LA technique is used?

Answer 20

long buccal infiltration

Question 21

what LA techniques would be used to probvide anaesthetic to the buccal gingivae of the lower premolars and canine?

Answer 21

• infiltration
• long buccal infiltration
• mental nerve block

Question 22

how would you anaesthetise the buccal gingivae of lower canines and incisors?

Answer 22

provide LA via buccal/labial infiltration

Question 23

how is a lingual nerve block provided?

Answer 23

when performing an IDB/IAN, on removal of the needle the remaining LA solution is deposited as the needle is withdrawn to provide anaesthetic to the lingual nerve

Question 24

how can the lingual gingivae of the mandibular arch be anaesthetised?

Answer 24

• lingual nerve block

- lingual infiltration

Question 25

how would you perform LA on a patient who is nervous?

Answer 25

• relaxation techniques such as deep breathing/playing music
• distraction techniques (pressing another area of the mouth with back of mirror, wiggling toes, talking to them etc.)
• apply topical anaesthetic to the area to reduce pain

Question 26

what are the steps of actually injecting the patient? (injection technique)

Answer 26

• position patient in chair
• dry mucosa & apply topical 1-2 minutes (pea sized)
• stretch mucosa and position needle at target point
• bevel of needle should be towards bone
• puncture mucosa quickly
• aspirate
• inject SLOWLY (no less than 30s)

Question 27

why is it important to aspirate when providing local anaesthetic to the patient?

Answer 27

to ensure you arent injecting into a blood vessel

Question 28

patient is booked for an extraction of their 14, what LA technique would you use?

Answer 28

• infiltration technique

Question 29

What LA is CITANEST?

Answer 29

Prilocaine HCL 3%

• amide type LA
• comes in plain or with FELYPRESSIN 1.2 micrograms

Question 30

What LA techniques would CITANEST be suitable for?

Answer 30

• infiltrations

- blocks

Question 31

Who is CITANEST not suitable for?

Answer 31

Pregnant women

Question 32

what is the max safe dose per kg for Lidocaine 2% plain/with epinephrine?

Answer 32

4.4mg/kg

Question 33

what is the max safe dose for prilocaine 4% plain/3% with felypressin?

Answer 33

6.0mg/kg

Question 34

what is the max safe dose per kg for Mepivicaine 3% plain/2% with epinephrine?

Answer 34

4.4mg/kg

Question 35

what is the max safe dose per kg for Articaine 4% with epinephrine?

Answer 35

7.0mg/kg

Question 36

what is the Max Safe Dosages equation for LAs?

Answer 36

(weight of person x dose) divided by mg per cart

Question 37

how many mg of anaesthetic are in a 2% strength LA?

Answer 37

44mg of LA

Question 38

how many mg of anaesthetic are in a 3% strength LA?

Answer 38

66mg of LA

Question 39

how many mg of anaesthetic are in a 4% strength LA?

Answer 39

88mg of LA