LA in children

Question 1

types of LA forms

Answer 1

amides

esters

Question 2

examples of amide LA

Answer 2

lidocaine

aptocaine

Question 3

examples of esters

Answer 3

procaine

Benzocaine

Question 4

how does aesthetic work

Answer 4

Chemical block between source of pain and brain

• Electrical signals pass as action potentials
• LA block the sodium channel, nerve signals cannot be transmitted

Question 5

function of vasoconstrictor

Answer 5

• slows removal of anaesthetic from the nerve vicinity

- prolongs anaesthetic action

Question 6

when to use LA in children

Answer 6

if the child is cooperative
procedure (removing mutliple or one filling)
effects of a painful experience, tolerance may change

Question 7

contradictions of use for LA

Answer 7

infection at injection site(consider use of block, pH in area may reduce potency of LA)

Question 8

contradictions of use for LA bleeding disorder

Answer 8

infiltration rather than block
block can cause sig haemorrhage
haematoma could develop

Question 9

contradictions of use for LA lidocainr

Answer 9

known hypersensitivity
acute porphyria (metabolic disorder, affects production of harm, accumulation an lead NS to attack causing damage to skin)

Question 10

contradictions of use for LA adrenaline

Answer 10

cardiac arythmias

hyperthyroidisms

Question 11

topical anaesthetic types/names

Answer 11

xylonor gel - 5% lidocaine
benzocaine gel - 20%
EMLA cream

Question 12

La solutions that are used

Answer 12

2% lidocaine with 1;80,000 adrealine
3% prilocaine with felypressin
articaine

Question 13

what is articaine good for

Answer 13

md infiltrations (good lipid solubility)

Question 14

contraindications for LA

Answer 14

patients with allergies to meatbisulfties

• methemoglobinemia or haemoglobinpathies
• associated with convulstions, anti convulsant meds can be used

Question 15

max doses of LA

Answer 15

1) Lidocaine
- 4.4mg per kg
2) prilocaine
- 6mg/kg
3) articaine
- 7mg/kg
- children 5mg/kg
4) bupivacaine
- 2mh/kg

Question 16

calculating children weight if unknown

Answer 16

Bodyweight (KG) = (age+4) x2

• estimate body weight if unknown
• watch for smaller/larger children

Question 17

calculating dose

Answer 17

Calculating dose

• weight 20kg
• max dose of lidocaine 4.4mg/kg
• max dose is therefore 4.4x20 gives 88mg

Mg in each cartridge
2% lidocaine =2g per 100g = 20 parts
per 1000ml = 20mg/ml
1 cartridge = 2.2ml=44mg

88mg/44mg gives 2 cartridge
10 years old at 30g, max 3 cartridges

Question 18

generalised dosage

Answer 18

general
1 cartridge per 10kg body weight lidocaine

Articaine, lower max dose
- 1 cartridge every 12.5 kg

Question 19

types of needles

Answer 19

1) infiltration
- 30 guage 2cm needle
2) block
- 27 guage 3 cm needle
- able to aspirate
3) intraligamental anaesthesia
- 30 guage
- 1cm needle

Question 20

needle desensitisation

Answer 20

1) explain and teach relaxation
2) needle uncovered inside mouth
3) needle on gingiva
4) injection

Question 21

max molar teeth permanent molar LA

Answer 21

• 1cm of bone covering roots of the permanent molars
• infiltration should be given above and distal to the BD root and the MB root
• Mesial and distal to the roots is more permeable

Question 22

palatal analgesia for children

Answer 22

use inter papillary method instead
Before interpapillary, perform buccal infiltration
- penetrate buccal papilla to depth of 1-2mm
- syringe barrel parallel to occlusal plane and perpendicular to line of arch
- inject slow and gently advance
Interpapillary
- observe blanching of the palate, takes 20to 30 secs
- repeat with other papilla until blanching joins
- aesthetic of complete gingival cuff is achieved
- can progress to palatal infiltration
- also useful in mandible (over 5 years)

Question 23

ID block technique

Answer 23

Mandibular foramen more distal and inferior

• level of lower occlusal place, approach rom 1stprimary molar on contralateral side
• 6-9 years old
• aspiration required
• long buccal injection
• block not on children younger than 6

Question 24

infiltrate vs ID block

Answer 24

Rule of 10
- count number of tooth from midline and add age
- answer is the max age at which infiltration alone is likely to give anaesthetic
- 10 or more look for ID block
if (age of pt) + (tooth #) < 10 = infiltration
With articane, rule of 12

Question 25

intraligamental technques

Answer 25

1) peri press system, high pressure, shielded barrels, protection
2) needle in interproximal perio sulcus at 50-60 angle to occlusal plane
3) gently advance until bony resistance felt
4) firm pressure to inject
5) backpressure
6) 0.4-6 mesially and distal to the tooth
7) immediate analgesia
8) lips/tongue not anaesthetised

Question 26

other delivery systems of LA

Answer 26

1) computer controlled delivery
- controls rate of admit
- slow delivery via line and needle
- useful for direct palatal analgesis
2) Jet injection
- needleless
- jet syringe injects LA solution under pressure through musocsa and bone
- useful for soft tissue analgesia prior to traditional LA methods

Question 27

reasons for LA failure

Answer 27

acute inflammation (- acidodsis reduces potency
- This is partly because most of the anaesthetic is ionized and therefore unable to cross the cell membrane to reach its cytoplasmic-facing site of action on the sodium channel.
)
incorrect site
insufficient LA
abnormal nerve supple
patient immaturity

Question 28

pain on injection

Answer 28

touching nerve (electric shock)
subperiostela injections

Question 29

complications post injection

Answer 29

lip tongue trauma
haematoma
vasovagal syncope
allergy and toxicity