local ana in dent

Question 1

Define analgesia?

Answer 1

Absence of sensibility of pain, particularly the relief of pain without loss of consciousness

Question 2

What do local anaesthetics do?

Answer 2

They eliminate sensations, especially pain, in one part of the body by the topical application or regional injection of a drug

Question 3

What do local anaesthetics block?

Answer 3

They block entry of sodium ions into cells therefore blocks action potential

Question 4

What are the 2 types of local anaesthetics?

Answer 4

1. Amino esters– largely superseded (cocain, Procaine)
2. Amino-amides: always have an i before the Caine bit: priolocain, lidocaine, mepivocaine, bupivacaine, articaine

Question 5

What is the most common local anaesthetic we administer and what is the dosage we give?

Answer 5

Lidocaine 2% plain or with epinephrine 1:80,000

Question 6

Describe Mepivacaine 3% plain 2% with epinephrine

Answer 6

It is plain and very short acting
Brand: scandonest

Question 7

How are local anaesthetics metabolised excreted?

Answer 7

1. Amino amides are metabolised by the liver| 2. Excreted via the kidneys

Question 8

What advise do manufacturers say about the use of lidocaine?

Answer 8

manufacturers advise caution in patients with liver disease

Question 9

Who should we avoid giving Felypressin?

Answer 9

Avoid in pregnancy
(Similar to oxytocin)

Question 10

Who should we taken caution in giving Adrenalin / Epinephrine?

Answer 10

Care in ischaemic heart disease, hypertensives, unstable angina

Question 11

What do Vasoconstrictors inc/ dec in local anaesthetics?

Answer 11

increase
-duration and depth of anaesthesia and reduce local blood flow
-increases length of action of local anaesthetic

Decrease
- lowers anaesthetic concentration in blood so decreases risk of toxicity
- decreases amount of bleeding at operation site

Question 12

How can the operator reduce the chances of getting a needle stick injury?

Answer 12

Do not re-sheath or re-use| Use safety-plus system

Question 13

How can patients have an allergy local cal anaesthetics?

Answer 13

Usually due to preservative| Was more common to ester-type (benzocaine, cocaine procaine).
Latex allergy may be triggered by rubber bung in cartridge. (Now more latex free but check packaging)

Question 14

What are some symptoms of local anaesthetic allergy?

Answer 14

1. Swelling2. Nausea malaise3. May lose consciousness4. Facial and laryngeal oedema

Question 15

What are Psychogenic reactions a patient could have to LA?

Answer 15

Feeling faint
Fainting
Palpitations
Panic attack

Question 16

What is a Vasovagal attack?

Answer 16

Fainting

Question 17

What should you do if your patient faints?

Answer 17

1. Lie them flat - head down
2. Loosen tight clothing
3. Call for help
4. Give them a Glucose drink
   If no improvement =
5. Check – airway, breathing, circulation
6. Oxygen if necessary
7. If not recovered in 2-3 minutes – assume not simple faint

Question 18

Who should we take care with when administrating adrenaline?

Answer 18

Recent myocardial infarction or coronary artery bypass graft

Care in hypertension and heart problems (especially if unstable)

Care when using on patients tricyclic antidepressants, SSRIs, diuretics

Question 19

What some adverse events that can occur when administering LA?

Answer 19

1. Broken needle (Rare)
2. Pain during or after
3. Haematoma
4. Trismus
5. IV injection
6. Blanching
7. Facial paralysis
8. Prolonged impaired sensation
9. Soft tissue trauma
10. Visual disturbances

Question 20

How can we make LA less painful?

Answer 20

• explain, reassure, tailor treatment
• Use topical properly
• Room temperature cartridges
• Careful needle placement
• pressure w mirror handle, stretch tissues
• SLOW injection controlled delivery.

Question 21

What symptoms can patients have is they get LA toxicity?

Answer 21

Effects on CNS and cardiac system:
Light headedness, dizziness, sedation, twitching

Can lead to Convulsions, loss of consciousness, respiratory depression and cardiovascular collapse

Question 22

How much LA is usually found in 1 cartridge?

Answer 22

2.2ml

Question 23

What is the maximum dose of lidocaine 2% we can give a health adult (70kg) ?

Answer 23

6.6mg/kg max 460mg (10.0 cartridges)

Question 24

What is the maximum dose of 4% articaine we can give a health adult (70kg)?

Answer 24

7.0mg/kg max 490mg (5.0 cartridges)

Question 25

What is the maximum dose of 3% Prilocaine we can give a health adult?

Answer 25

9.0mg/kg max 600 (19 cartilage)

Question 26

What is the maximum dose of 2% mepivacaine plain| we can give a health adult?

Answer 26

4.4mg/kg max 300ml (14 cartridges)

Question 27

What is the maximum dose of 3% Mepivacaine| we can give a health adult?

Answer 27

4.4mg/kg max 300mg (9 cartridges)

Question 28

What should we beware of with the elderly?

Answer 28

Over the age of 65 liver function in the elderly reduces by 60% Therefore reduce safe dosages by 50%

Question 29

Which causes of LA failure are operator dependant vs patient dependent?

Answer 29

Operator= choice of technique and solution, Poor technique Patient= anatomical, pathological (infection), psychological (anxiety)

Question 30

Define anaesthesia

Answer 30

Partial or complete loss of sensation, with or without loss of consciousness, a result of disease, injury, or administration of an anaesthetic agent, usually by injection or inhalation

Question 31

Define LA

Answer 31

A temporary loss of sensation in one small area of the body caused by special drugs called anaesthetics. The patient is conscious, but without feeling in the area of the body treated with the anaesthetic.

Question 32

Define Paraesthesia

Answer 32

Abnormal sensation (not specifically unpleasant), spontaneous or evoked

Question 33

Define Dysesthesia

Answer 33

Unpleasant abnormal sensation, spontaneous or evoked

Question 34

Define hypoaesthesia

Answer 34

Reduced perception of stimulus or decreased sensation

Question 35

What are amino esters metabolised from?

Answer 35

pseudocholinesterase in the blood to form Amino esters metabolised by para-aminobenzoic acid - can cause an allergic reaction

Question 36

Describe Lidocaine 2% plain or with epinephrine 1:80,000 (i.e. 1:80k)

Answer 36

Most common, very effective Brand: Lignospan special, Lignocaine, Xylocaine etc

Question 37

Describe Prilocaine 4% plain or 3% with felypressin

Answer 37

Similar to lidocaine Brand: Citanest, Citanest with octapressin

Question 38

Articaine 4% with 1:100,000 or 1:200,00 epinephrine

Answer 38

Better diffusion, fast onset, hydrolysed quickly, not for IDBs Brand: Septonest

Question 39

Describe Bupivacaine 0.25%,0.5%,0.75% ampoules

Answer 39

Slow onset but long duration – 2 hours pulpal anaesthesia Brand: Marcaine and Sensorcaine

Question 40

Types of local anaesthetics

Answer 40

a) Prilocaine 3% and octapressin 0.03 IU per ml b) Mepivicaine 3% plain c) Articaine 3% and 1:10k epinephrine d) Lidocaine 2% and 1:80k epinephrine

Question 41

What must we avoid when giving LA?

Answer 41

• Intravascular injection (haematoma, systemic effects, ischaemia) - always use aspirating syringe

Question 42

Complications of LA

Answer 42

Psychogenic reactions – ask anxiety levels LA toxicity Allergy Drug interactions

Question 43

How could an allergic reaction be mimicked?

Answer 43

Psychogenic reaction- Patients often have a blush or erythema which mimics allergic reactions, hyperventilation, nausea, and vomiting

Question 44

Equation to calculate max dose?

Answer 44

Safe max number of local anaesthetic cartridges = Max safe dose of local anaesthetic (mg) x patient weight (kg) ________________________ Amount of local anaesthetic per cartridge

Question 45

Mild allergy vs anaphylaxis

Answer 45

Mild= urticaria and rash, particularly of chest, hands and feet Mild bronchospasm without evidence of severe shortness of breath E.g Rhinitis, conjunctivitis Anaphylaxis= wheezing Tachycardia (heart rate >110 per minute) and inc respiratory rate

Question 46

Symptoms of anaphylaxis

Answer 46

Abdominal pain, vomiting, diarrhoea, impending doom Flushing, but pallor may also occur, Mild allergy

Question 47

Intra-oral topical anaesthetics

Answer 47

• Xylonor® Gel 5% lidocaine analgesic gel • 20% Benzocaine Topical Anaesthetic bubble gum flavour • Lidocaine 4% ointment or gel • 10% Lidocaine intraoral spray • Oraqix ® (Lidocaine and Prilocaine periodontal gel) 2.5% / 2.5%

Question 48

Extra-oral (skin) topical anaesthetic

Answer 48

• EMLA - 2.5% / 2.5% Lidocaine and Prilocaine • AMETOP – 4% tetracaine

Question 49

How to apply topical anaesthetic

Answer 49

1)Dry the area of needle placement with cotton wool roll 2) Place a pea sized amount of topical anaesthetic onto a cotton wool roll or pledget and tweezers and place onto area of needle placement and wait for a 2 to 3 minutes 3) Perform you local anaesthetic injection

Question 50

How should you communicate to a patient while delivering LA?

Answer 50

DONT: needle or injection, negative phrases e.g. ‘this might hurt’ DO: Explain using ‘neutral’, age-appropriate phrasing Explain what to expect post-op e.g. duration of anaesthesia and care not to cause inadvertent soft tissue trauma