ICP-33 Infiltration Anaesthesia Flashcards
What questions and procedures need to be asked/done before a procedure involving LAs
- Does the procedure actually need LA?
- Is LA safe for patient?: allergy, medications etc
- What procedure?: all nerves or main supply?
- What nerves to anaesthetise? : infiltration/block?
- Gain consent: why, risk and benefits
- Prepare LA syringe - correct length and gauge
Before loading a cartridge what are things that need to be checked
- Check type of anaesthetic is appropriate for patient
- If it is in date
- No evidence of damage
- Solution is clear
- No air bubbles or other contamination
What is infiltration anaesthetic
Inject LA near tooth to allow solution to infiltrate and affect local nerve endings
What teeth can we use infiltration anaesthesia on
All maxillary teeth and the anterior mandibular teeth due to thin cortical plate
Where do we want to deposit LA in the oral mucosa
Need to penetrate through the full thickness of the epithelial layer and deposited in the CT layer and just above the periosteum, bone should not be contacted
What happens if we inject solution into the epithelial layer
Will cause a blister that can cause discomfort
Why do we need to aspirate the patient/specific area of oral mucosa when injecting LA
To prevent us from injecting LA into a blood vessel of which there are many in the CT layer
What is the aim of aspiration and how do we carry it out
Aim: to avoid intravascular injections
Safety syringes are self aspirating that means that negative pressure is made in the cartridge and draws blood into the cartridge if the needle is in a vessel.
Once the needle passes through the epithelium and before delivery check the cartridge before delivery.
If you see blood, which is rare, just do it again
How should patients be seated when delivering LA
Horizontal ideally but if anxious and wants to sit up, try to compromise and tilt chair back about 30 degrees
What steps are involved in delivering infiltration LA
- Apply topical anaesthetic: clean and dry mucosa, use cotton roll and retract lip, allow 3-4 mins for anaesthesia
- Retract soft tissue fully
- Needle entry: depth of buccal sulcus, above selected tooth, stretch tissues taut
- Aspiration: insert needle gently and directly in one continuous movement to the target area, remember to aspirate - gently push plunger and then release
- Deliver LA solution: apply gentle pressure continuously, 1ml over 30 seconds
- Withdraw needle: place needle on bracket table and pull down safety sheath, check patient is ok, may want to rinse mouth
What needle do we use for maxiallry buccal infiltrations
- 30 gauge
- Short needle
- Lidocaine with adrenalin (1:80,000)
Providing buccal infiltration to the upper left second pre molar what would become anaesthetised
- Pulp of upper left second premolar
- Soft tissue and PDL of upper left second premolar
- Pulp of the upper left first molar
- Pulp of the upper left first premolar
In palatal infiltration where do we tend to deposit solution
- Just distal to the tooth of interest
- Infiltrate into the palate 10-15mm from the gingival margin (fleshy)
What are palatal injections uncomfortable
As there isn’t a lot of space for LA solution beneath the epithelial layer
What needle is used for anterior mandibular buccal infiltrations
30 gauge short needle
deposit 1ml over 30 seconds
