LA for children

Question 1

What is surface anaesthesia

Answer 1

Anaesthesia of the surface tissues i.e. skin or mucous membranes

Question 2

What is surface anaesthesia used for

Answer 2

To reduce pain of local anaesthesia injection​

To reduce discomfort of venepuncture​

For superficial soft tissue manipulation​

Question 3

What are the typs of surface anaesthesia

Answer 3

Physical (refrigeration)
Pharmacological (topical)

Question 4

What is the technique for successful anaesthesia with topical

Answer 4

Dry area​

Apply over limited area (use a cotton wool roll)​

Apply for sufficient time: 2 mins

Question 5

What depth of tissue can topical anaesthetise

Answer 5

2-3mm

Question 6

When might topical be used

Answer 6

Pre-injection​

Rubber dam clamp​

Placing matrix band​

Suture removal​

Exfoliating primary teeth​

Subgingival scaling​

Incision of abscess​

Question 7

What topical anaesthetics can be used on skin (extraoral)

Answer 7

EMLA cream
Ametop gel

Question 8

How do topical patches work

Answer 8

Incorporation of local anaesthetic into materials that adhere to the mucosa and allow slow release​

Decreases the chance of the anaesthetic moving away from the application site​

Question 9

What are the advantages and disadvantages of topical jet injectors

Answer 9

Advantages​
-Allows anaesthesia up to 1cm​
-Bleeding diatheses where deep injections are contraindicated​
-Sole means achieving LA​
-Prior to conventional techniques​

Disadvantages​
-Could cause soft tissue damage if careless​
-Frightening sight and sound​
-Taste of solution​
-Expensive!!!!​

Question 10

When might temperature have an effect on perceived discomfort

Answer 10

under 15 degrees

Question 11

What are the properties of lidocaine 2% with 1:80,000 adrenaline

Answer 11

Amide ​

‘Gold Standard’ local anaesthetic​

rapid onset of action and half-life = 1.5 -2hrs​

suitable for infiltration, block, and surface anaesthesia

Question 12

What advantages does LA with adrenaline have

Answer 12

More profound anaesthesia​

Longer lasting pulpal anaesthesia​

Haemorrhage control

Question 13

What is an alternative vasoconstrictor from adrenaline

Answer 13

Felypressin/octapressin

Question 14

What is the half life of lidocaine

Answer 14

1.5-2 hrs

Question 15

What are the contrainfications to Lidocaine

Answer 15

If the patient has a heart block and no pace makers
Any allergy to LA/or to corn
Hypertension
impaired liver function

Question 16

Why should 4% solutions be avoided

Answer 16

Higher risk of non-surgical paraesthesia
Shouldnt be used in patients with sickle cell anaemia or other haemoglobinopathies

Question 17

What is the wand STA instrument

Answer 17

Computer-aided anaesthetic system​

Allows for controlled adminstration of local anaesthetic​

Can be used for infiltrations, blocks, intra-ligamentary and single tooth anaesthesia​

Question 18

What are the technique/modifications for injecting LA in children

Answer 18

Infiltration​

Intra-ligamentary​

Regional block

Question 19

What sizes of needles are available to LA

Answer 19

Long - ID block 35mm yellow
Short - 25mm blue
Ultra short - 10mm purple

Question 20

When can infiltrations be used

Answer 20

Primary teeth
Maxillary permanent teeth
Mandibular permanent anterior teeth
Before intrapapillary and intra-ligamental in posterior permanent teeth
Before palatal/lingual anaesthesia

Question 21

What are the steps to giving a buccal/labial infiltration

Answer 21

Dry mucosa​

Topical Anaesthetic (2 mins)​
-Wipe off excess​

Stretch mucosa​

Distract patient ​
-gentle pressure or rubbing on lip, talking, singing​

Insert needle ​
-ultra short or short needle​
-Directed at apex of the tooth​

Aspirate​

Inject supra-periosteal as close as possible to apices of teeth​
-0.5ml – 1ml should be suffice pulpal anaesthesia​

Question 22

How is intra-papillary infiltration carried out

Answer 22

Draw an imaginary line across the base of one of the interdental papillae​

Draw a perpendicular line through the middle of the papillae​

Insert the needle horizontally, to pass between the teeth on each side​

Advance the needle 1-2mm and wait a few seconds, and advance again​

Ensure the needle does not become obstructed on the inter-septal bone or emerge from the gingivae​

After blanching is seen, insert the needle into the blanched area

Question 23

How do you carry out an intraligamental injection

Answer 23

Intra-osseous via cancellous space via PDL​

0.2ml per root – beware excess dose​

More successful with a vasoconstrictor​

Ultra short 30-gauge needle​

30 degree to long axis of tooth in mesio-buccal gingival sulcus – advance until resistance​
-Specialised syringe measured dose​
-Conventional syringe – 0.2ml is width of bung​

Question 24

How is the mandibular foramen different in children compared to adults

Answer 24

Below the occlusal plane
Lower than in adults

Question 25

How is does the needle approach the inferior alveolar and lingual nerve in children

Answer 25

Advances from the primary molars on the opposing side with the syringe held parrallel to the occlusal plane

Question 26

What anatomical features should be remembered while administering nerve block

Answer 26

The needle inserted through the mucosa in the mandibular retromolar region lateral to the pterygomandibular raphe, midway between the raphe and the anterior border of the ascending ramus of the mandible, aiming for a point half-way between the operator’s thumb and finger​ The height of insertion is around 5mm above the mandibular occlusal plane​ The needle is advanced until the medial surface of the mandible is reached​ In young children bone will be reached after about 15mm, therefore a 25mm needle can be used​ In older children, bone may be reached at 25mm, therefore a 35mm needle is required​ Once bone has been touched, the needle is withdrawn slightly until it is supra-periosteal, aspiration performed, and around 1.5ml of solution is deposited. ​ Withdraw halfway, aspirate again, and deposit the remaining solution for a lingual nerve block​

Question 27

How is the needle positioned for a mental/incisive nerve block

Answer 27

Advance needle in buccal sulcus toward region between apices of 1st and 2nd primary molars.​

Question 28

What are the advantages and disadvantages to a mental and incisive nerve block

Answer 28

Advantages​ -very good soft tissue anaesthesia Disadvantages​ -Incisive nerve anaesthesia not as reliable as IDB ​ -Incisors may get crossover supply across midline so need a labial infiltration adjacent to tooth as well as this block​

Question 29

What is a psychogenic complication of anaesthesia and how to prevent it

Answer 29

Fainting - the chances of this happening are reduced by sympathetic management and administration of the anaesthetic to children in a semi-supine position​

Question 30

What are the maximum safe doses of each anaesthetic

Answer 30

Lidocaine 2% plain / with epinephrine:​ 4.4mg/kg​ Prilocaine 4% plain / 3% w felypressin:​ 6.0mg/kg​ Mepivicaine 3% plain / 2% w epinephrine:​ 4.4mg/kg Articiane 4% with epinephrine​ 7.0mg/kg

Question 31

Lidocaine​ 2% soln in 2.2ml cartridge contains 44mg What is the max safe dose for a 5 year old 20kg child

Answer 31

20kg x 4.4 = 88mg = 2 cartridges​

Question 32

What a 5 year old 20kg child what is the safe dose of prilocaine and articaine

Answer 32

Prilocaine ​ 3% soln in 2.2ml cartridge contains 66mg​ Max safe dose is 6.0mg/kg ​ 20kg x 6 = 120 mg = 2/11 short of 2 cartridges​ Articaine​ 4% soln in 2.2ml cartridge contains 88mg​ Max safe dose is 7mg/kg​ 20kg x 7 = 140mg= 1.6 Cartridges​

Question 33

What are the effects of LA toxicity

Answer 33

Cardiovascular ​ -low levels – stimulant ​ -high levels - circulatory collapse CNS ​ -Depressant leading to unconsciousness and respiratory arrest Methaemoglobinemia ​ -Cyanosis associated with lethargy and respiratory distress​ -Ferrous iron of normal hemoglobin is converted to the ferric form, which cannot combine with​ -Prilocaine​

Question 34

What are the steps to treating toxicity

Answer 34

Stop treatment Provide BLS Call for medical assistance Protect patient from injury Monitor vitals

Question 35

What are early localised complications of LA

Answer 35

Pain Failure of LA Motor nerve paralysis Haematomaformation

Question 36

What are late localised complications of LA

Answer 36

Self inflicted trauma​ Oral ulceration​ Long lasting anaesthesia​ Trismus​ Infection ​ Developmental defects

Question 37

What are behaviour managed techniques to use when giving LA to a child

Answer 37

Distraction Tell-show-do Acclimatisation Role modelling Voice control