LA Complications Flashcards
List features of the LA lidocaine (3)
- Amide type
- Lidocaine HCL 2%
- Vasoconstrictor:
With adrenaline 1: 80,000
Plain (none)
List features of the LA Citanest (3)
- Amide type
- Prilocaine HCL 3%
- Vasoconstrictor:
With Octapressin
Plain
List features of the LA Articaine
- Amide type
- 4% with adrenaline
- Comes in a variety adrenaline concentrations
1: 100,000
1: 200,000
1: 400,000
Uses of:
Lidocaine
Citanest
Articaine
Infiltrations
Blocks
Does Mepivicaine 3% plain contain a vasoconstrictor?
No
Mepivicaine working time for infiltration?
20 mins
Mepivicaine working time for a block?
40 mins
Mepivicaine working time for soft tissue anaesthesia
2 hours
Does lignocaine 2% HCl contain a vasoconstrictor?
1:80,000
Adrenaline
Lignocaine working time for infiltration?
60 mins
Lignocaine working time for a block?
90 mins
Lignocaine working time for a soft tissue anaesthesia
3-5 hours
Does articaine 4% HCl contain a vasoconstrictor?
Adrenaline
1:100,000
1:200,000
1;400,000
Articaine working time for infiltration?
Up to 120 mins
Articaine working time for a block?
75 mins
Articaine working time for soft tissue anaesthesia
3-5 hours
Does Prilocaine HCl 3% contain a vasoconstrictor?
Octapressin
Prilocaine working time for infiltration?
30-45 mins
Prilocaine working time for a block?
60 mins
Prilocaine working time for a soft tissue anaesthesia?
3-6 hours
List systemic complications of LA (6)
- Psychogenic
- Interaction with other drugs
- Cross infection
- Allergy
- Collapse
- Toxicity
List the main psychogenic/stress complications of LA (7)
- Fainting
- Palpitations
- Cold sweat
- Restlessness
- Excitation
- Trembling
- Weakness
Whats the reason for psychogenic/stress complications?
Lack of oxygenated blood to the brain
What clinical features can present with psychogenic complications (6)
- Lightheadedness
- Pallor
- Beads of sweat
- Bradycardia (slow pulse)
- Nausea
- Pupil dilation
How are these psychogenic complications managed? (4)
- Lay flat and raise legs
- Loosen neck clothing
- Improve room ventilation
- Sweet drinks
List some examples of other drugs LA may interact with (3)
- B blockers
- Cocaine - increased adrenergic activity
- Tricyclics - risk of hypertension
What are most allergic reactions to LA due to?
Mostly due to preservatives
List some toxicity complications with LA (4)
- Convulsions
- Loss of consciousness
- Respiratory depression
- Circulatory collapse
How can toxic effects of LA be reduced? (2)
- By use of an aspirating technique
2. Rate of introduction (injection) should be slow, thereby decreasing the chance of overload
Max dose of Mepivicaine 3%
3 mg/kg
Mgs within a Mepivicaine 3% cartridge
66 mgs
Max number of Mepivicaine cartridges (70kg adult)
6
Max dose of Lignocaine 2%
5 mg/kg
Mgs within a Lignocaine 2% cartridge
44 mgs
Max number of Lignocaine cartridges (70kg adult)
7
Max dose of Articaine 4%
7 mg/kg
Mgs within Articaine 4% cartridge
88 mgs
Max number of Articaine cartridges (70kg adult)
5
Max dose of Prilocaine 3%
8 mg/kg
Mgs within Prilocaine 3% cartridge
66 mgs
Max number of Prilocaine cartridges (70kg adult)
8
List the effects of adrenaline on the heart (4)
Via B1
- Rate increases
- Force increases
- Output increases
- Excitability increases
List the effects of adrenaline on the vessels (3)
Via B2
- Coronary dilation
- Skin contraction
- Muscle dilation
Give the effects of adrenaline on the blood pressure (2)
- Systolic pressure increases
- Diastolic pressure decreases
Overall - little effect
Give the effects of adrenaline on the lungs
Via B2
Bronchial muscle - relaxation
List some dangers of adrenaline in LA (4)
- CVD
- Hyperthyroidism
- Hypertension
- Drug interactions
List some local complications of LA (7)
- Failure to achieve anaesthesia
- Prolonged anaesthesia
- Pain during/after injection
- Trismus
- Haematoma
- Blanching
- Soft tissue damage
Give some causes of prolonged anaesthesia with LA (3)
- Direct trauma from needle
- Multiple passes with same needle
- Chemical trauma for direct injection
Different depending on LA used
How does trismus affect the patient
Muscular spasm so can’t open mouth very wide and this can be very frightening for the patient
Describe the presentation of trismus
Within a few hours of IAN block it may severely restrict opening and it may last for weeks or months
List the causes of trismus (3)
- Damage to medial pterygoid
- Injection too low
- Injection too rapid
Describe the management used for trismus (3)
- Reassurance (after diagnosis)
- Muscle relaxant
- Anti inflammatories
Describe the presentation of facial palsy from LA
Usually complete unilateral motor nerve paralysis within minutes of inferior dental blocks
How does LA induced palsy present?
LA has been deposited in an area that affects all facial nerves so they can’t move that side of their face at all
How does a stroke present?
During a stroke they may not be able to use muscles in lower half of the face but can wrinkle forehead and close eye
Upper spares upper
(If patient has an upper motor neurone defect - stroke it spares the upper branches of the facial nerve)
How does LA injection lead to facial palsy?
LA into parotid gland as
injection was too far posteriorly instead of touching the bone
How is LA facial palsy diagnosed?
Testing the 5 branches of the facial nerve
How is a case of LA facial palsy confirmed?
Temporal branch affected
Lower motor neurone distribution
What is the management for LA facial palsy
Reassurance _ cover eye with pad until blink reflex returns
List the effects of intravascular infection due to LA (3)
- Skin blanching
- Visual disturbance
- Aural disturbances
What LA technique could result in an intra-vascular injection
IAN dental block
How is intra-vascular injection with LA avoided? (4)
- By careful technique
- Aspirating system
- Slow drug introduction
- Safe quantity
Symptoms of intravascular LA injections (6)
- Palpitations
- Anxiousness
- Restlessness
- Sweating
- Headache
- Pallor
