Local Anaesthetic Flashcards

1
Q

What nerve supplies the maxillary teeth?

A

Anterior, middle and posterior branches of the maxillary division of Trigeminal nerve (CN V)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What nerve supples the soft tissues of the palatal surfaces?

A

Long sphenopalatine nerve and greater palatine nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

For papillary injections where is the needle injected?

A

Roughly at level of cervical margin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What nerve supplies the lower teeth?

A

Mandibular division of the Trigeminal nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What nerve supples the lingual soft tissues of lower teeth?

A

Lingual nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What nerve supplies the buccal soft tissues?

A

Long buccal nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the duration of action of Lidocaine on the pulp?

A

1hr (60 mins)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the duration of action of Lidocaine on soft tissue?

A

170mins (just under 3 hours)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the duration of action of Articaine on the pulp?

A

60mins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the duration of action of Articaine on the soft tissue?

A

190mins (just over 3 hours)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which 2 LAs contain adrenaline?

A

Lidocaine and Articaine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which LA can be used when adrenaline is contraindicated?

A

Prilocaine (with Felypressin) and Mepivacaine (plain solution)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the maximum dosage of Lidocaine that can be given to a patient (assuming 70kg)?

A

4.5 cartridges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the maximum dosage of Articaine that can be given to a patient (assuming 70kg)?

A

4 cartridges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Should you use Articaine on a pregnant patient?

A

NO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which patients should you be cautious with when using articaine?

A

Lung disorders (asthma), liver/kidney/thyroid problems, Diabetes mellitus, history of epilepsy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What percentage of Lidocaine and adrenaline is present?

A

Lidocaine Hyderochloride (2% and adrenaline 1:80,000)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What percentage of Articaine and adrenaline is present?

A

Articaine 4% and Adrenaline 1:100,000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What percentage of Prilocaine Hydrochloride and felypressin is present?

A

Prilocaine hydrochloride 3% and felypressin 0.03 IU/ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When might you use mepivacaine hydrochloride ?

A

When the use of vasoconstrictor is contraindicated (pt with severe hypertension or unstable cardiac rhythm)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the landmarks for buccal infiltrations?

A

Mucobuccal fold parallel to the long axis the tooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the dosage for maxillary infiltrations

A

Up to 1/2 cartridge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What does the nasopalatine block anaesthetise?

A

Anterior portion of the hard palate (both hard and soft tissues) from the mesial aspect of the right and left premolars

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are landmarks for nasopalatine block?

A

Central incisors, incisive papilla and incisive foramen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is in the inject site for a nasopalatine block?
Soft tissue just lateral to the incisive papilla, 1cm palatal to the maxillary central incisors
26
What is the dose for a nasopalatine block?
Until tissue blanches
27
What does the greater palatine block anaesthetise?
Posterior portion of the hard palate both hard and soft tissues distal to the canines and medial to midline
28
What are the landmarks for the greater palatine block?
Greater palatine foramen
29
What is the injection site for a greater palatine block?
Soft tissue just anterior to the depression created by the greater palatine foramen, usually distal to the upper 2nd molar but it can be more anterior
30
What is the dose for a greater palatine block?
Up to 1/2 cartridge
31
What does an ID block anaesthetise?
All teeth in the quadrant, buccal soft tissues from mental nerve to midline, tongue and lingual soft tissues
32
How long is a blue needle?
2.5cm
33
How long is a yellow needle?
3.5cm
34
What is the dose for an ID block?
1 cartridge
35
What is the dose for mental block?
No more than 2/3 cartridge
36
What does the long buccal block anaesthetise?
Soft tissues and periosteum buccal to the Mandibular molars
37
What are the landmarks for a long buccal block?
Mandibular molars and the mucobuccal fold
38
What is the injection site for long buccal block?
Distal and buccal to the most distal molar in the arch on the anterior border of the ramus
39
What is the dose for a long buccal block
No more than 1/2 cartridge
40
What are analgesics?
Pain reliever or pain killer
41
What is Trigeminal neuralgia?
Sudden, severe facial pain - often described as a sharp, shooting pain Thought to be caused by compression of the Trigeminal nerve
42
What is local anaesthetic?
Drug that causes reversible local anaesthesia and loss of nociception (the neural processes of encoding and processing noxious stimuli)
43
How do LAs work with impulse conduction?
They reversibly block impulse conduction along nerve axons and other excitable membranes that use sodium channels as the primary means of action potential (nerve impulse) generation
44
What are some ideal properties of LA?
Stable in solution, non-irritating to tissues, no permanent damage to nerves, no systemic toxicity, no allergic response, potent, rapid onset of action, predictable duration of action, sensory > motor, no active metabolites
45
What are the 2 main groups of LA
Amide and esters
46
What is the mechanism of action of LA? What are they trying to target?
Trying to target sodium or ion channels
47
How does LA work (in terms of Na+ ion channels)?
In order for voltage gated sodium channels to open is a change in voltage LA passes through the cell membrane through the cytoplasm to the binding site LA inhibits the influx of Na into the neurone (by blocking sodium channels) which means action potential (nerve impulses) cannot arise and signal conduction is inhibited. Because the signal does not get passed to the brain, the pt can’t detect the firing
48
What is the order of sensitivity to LA inhibition?
Autonomic > cold > warmth > pain (first pain is A(alpha) fibres, then C fibres) > touch > deep pressure
49
How does inflammation reduce the action of LA?
Inflammation can cause acidosis which is an increased acidity of the blood plasma (acidosis is when arterial pH falls below 7.35) Most of the anaesthetic is ionised and therefore, unable to cross the cell membrane to reach its cytoplasmic-facing site of action on the sodium channel - Only non-ionised LA diffuses readily across cell membrane and being ionised (in acidic conditions) does not allow it to reach the binding site on the intracellular portion of the sodium channel
50
What type of pain presents with c fibres?
Dull, long lasting
51
What type of pain is presented with A(alpha) fibres?
Short, sharp pain
52
What does anaphylactic mean?
Allergic reaction
53
Which LAs are amides?
Lidocaine, Prilocaine, articaine (contains both ester and amide) bupivacaine, mepivacaine
54
Which LAs are ester based?
Benzocaine, procaine, tetracaine
55
What are some examples of LA toxicity?
Hypersensitivity (allergic response) or reaction to preservatives CNS (initial effects are excitatory with involuntary muscle activity; later effect is depressant which may lead to unconsciousness and respiratory arrest Cardiac (possible reduction in cardiac output may lead to circulatory collapse)
56
Why is LA often given with vasoconstrictors?
- prolongs action - reduces plasma levels (less risk of CNS effects) - greater anaesthesia or reduced dose
57
What are some reasons for failure of LA?
Insufficient solution injected Inaccurate placement Intravascular injection Biological variation Anatomical variation Infection or inflammation
58
What kinds of symptoms with allergy to LA?
Swelling Nausea malaise May lose consciousness Facial and laryngeal oedema (swelling)
59
What do you do in a vasovagal attack? (Faint)
Lie flat (head down) Loosen tight clothing Call for help Glucose drink Check airway, breathing, circulation Oxygen if necessary If not recovered in 2-3mins assume not a simple faint
60
What are the drug interactions with adrenaline?
Interactions with antidepressants MAOIs (possibly tricyclics) Care in hypotension and heart problems (especially if condition is unstable)
61
What are the drug interactions with felypressin
DO NOT use in pregnancy