Pedo Local Anesthesia Flashcards
What directs the type of anesthetic you will use?
Patientt medical history Patient mental/development status Anticipated duration of procedure Need for heme control Other agents planned (Nitrous oxide, General Anesthesia, sedation) Practitioner knowledge
What are the benefits of vasoconstrictors?
Limits systemic distribution of local Increases duration of local
What type of local anesthetic is usually used for pedo cases?
Shorter acting
2% Lido
4% Septo
Why give a shorter acting local for pedo?
Decrease post-op trauma
How should children be considered physiologically?
Not little adults. Anatomy and physiology is different with different size, shape, and location of foramina and landmarks, pharmacology is different, psychology is different (decreased ability to cooperate or verbalize)
What is characteristic of children cardiovascular compared to adults(cardiac output and oxygen consumption)?
Higher cardiac output
Higher oxygen consumption
Higher output with higher baseline heart rate
Normal pedo HR are higher or lower than adults?
Higher Heart rate
Normal pedo BP is higher or lower than adults?
Lower
Is the volume of distribution of drugs increased or decreased in adults?
Increased volume of distribution
With respect to the increased vol of distribution, what does that mean for the pedo plasma level if a standard dose is given?
Lower plasma level than adults
Is the minute volume increased or decreased in children and what does this mean for cardiac output?
Minute volume increased with corresponding increased cardiac output
With respect to the increased vol of distribution, what does that mean for the pedo respiratory rate if a standard dose is given?
Respiratory rate increases
What are the 5 main differences between adult and pediatric airway?
- Proportionally larger head and tongue
- More anterior and cephalad larynx
- Long floppy epiglottis
- Short trachea and neck
- Narrowest point is cricoid cartilage
What is the anatomy of the pedo zygomatic process?
Closer to the maxillary alveolar bone
Over which teeth is the zygomatic process prominent in pedo?
Over apices of Max 1st perm molar and primary 2nd molars
Is pedo maxillary bone more porous or less porous?
More porous, can infiltrate easier
Is a shorter depth of needle required for maxillary local anesthesia?
Shorter depth
Where is the mandibular foramen(Lingula for the IAN) located in pedo?
More inferiorly and posteriorly, approximate level of occlusal plane
Pedo mental foramen faces anteriorly or posteriorly?
Anteriorly
What is the insertion depth for local in the mandible?
Shorter depth of needle
How does mandible grow?
Down and forward
How long should topical be left over the injection site to be effective?
90-120 seconds
Can patients tell difference between size 25,27,30 needles and which one has the most separations associated?
Can’t tell difference. 30 has most separations. Therefore pick the larger guage, except extra short only comes in 30 guage
What is the length of the extra short needle?
12mm
What is the length of the short needle?
21mm
What is the length of the long needle?
30mm
What needle length is suitable for children under 6 yrs old?
Short
What needle type is ideal for maxillary anterior infiltrations?
Extra Short
Where can needle be bent for papillary and PDL injections?
At hub and only once
What areas are anesthetized with the IAN block?
Mandibular teeth to midline
Body of mandible
Anterior 2/3 of tongue
Lingual soft tissue and periosteum
What are some indications for IAN?
Multiple teeth to be restored in one quadrant
What is the Gate Theory?
Stimulate nerve impulses (e.g. cheek shaking) lessens pain on insertion
Which is usually more painful, tissue distention or needle insertion?
Tissue distention
Should you make sure IAN block is successful before doing the Long Buccal and why?
Yes, Long Buccal can mask unsuccessful IAN
Over what landmark should the barrel of the syringe be placed when giving a pedo IAN?
Over opposite side primary molars
What is the IAN success rate in pedo?
High (90-95%)
What gives possible accessory innervations to mandibular anteriors and molars?
Mylohyoid nerve (branched off IAN before mandibular canal)
What is the mylohyoid injection landmark?
Below mylohyoid groove aiming at apex of 2nd molar lingual aspect
What nerve is blocked if following areas are anesthetized: anterior mandible, 2nd primary molar to the ipsilateral central incisor, buccal soft tissues , and pulp in pedo?
Mental nerve block
Should the needle bevel be towards or away from bone in mental nerve block?
Towards the bone
Which direction does the mental foramen face in pedo?
Anteriorly
Can mandibular infiltrations be done in pedo?
Yes, because the bone is less dense
What is the drawback of mandibular infiltration versus IAN?
Infiltrating may have shorter duration
When is a PDL injection contraindicated?
When there is inflammation/infection at injection site
Is the PDL injection a primary or supplemental injection?
Supplemental
What are the advantages of the PDL injection?
Mminimize post op bleeding
Good for patient with bleeding disorder
Specific teeth anesthetized with minimal residual anesthesia resulting in less post op discomfort and trauma
What are the post-op instructions for for a patient who received anesthesia?
No chewing until anesthesia has worn off, soft diet then work up as anesthesia wears off, can be numb >1 hr post op
What are some common post op anesthesia soft tissue traumas?
Biting lip, tongue, cheek
What is the procedure if post op anesthesia soft tissue injury occurs?
See pt within 24 hrs. advise warm saline rinse
What is used more commonly on maxilla: local infiltration or PSA, MSA, ASA?
Local infiltration
What is an indication for maxillary local infiltration?
Minimal restoration needs
If extracting maxillary teeth, where should you always administer anesthesia?
Palatal
What other procedure indicates palatal infiltration?
Seating stainless steel crowns
What is the depth of insertion for anterior injections?
1.5-2.0 mm
What is the technique if multiple teeth require anterior injection?
Maintain same injection site but move needle
What should be done with patient’s head while giving anterior infiltrations to avoid trauma to patient or self?
Support head
What is an alternative to palatal injection?
Interdental papilla infiltration at base of papilla triangle. Allow 3-5 min to work
What is a better technique for patient management: nasopalatine block or interdental papilla infiltration?
Interdental papilla infiltration
What is a landmark to use when giving the greater palatine injection?
10 mm posterior to distal surface 2nd primary molar at depression in palate
What are some methods to block pt vision of needle?
Light in the eyes
Nitrous hood obstruct vision
Pass instruments out of patient line of sight
What are the 3 parts of local anesthetic?
Lipophilic aromatic ring (non-ionized for lipid solubility)
Amide chain
Terminal Amine (determines charge, water solubility)
What part of the anesthetic blocks the Na channel?
Ionized
If surrounding tissue pH is lower (infection), what will be the character of the local given?
More ionized, therefore unable to diffuse
By blocking Na channels what does local due to the nerve?
Slows rate of depolarization so threshold not reached (increases threshold?)
All Amide locals have what where in their name?
An “I” in the portion before –caine Articaine Prilocaine Mepivicaine Lidocaine Bupivicaine Etidocaine
What is the amide metabolism site ?
Liver
What are 2 places where prilocaine is metabolized?
Primarily liver, but also lung
Where are esther locals metabolized?
Plasma by psuedocholinesterase
What is the definition of pKa?
The pH at which 50% of drug is charged vs uncharged?
The pKa determines what?
Onset of action
The farther the pKa is away from physiologic ph (7.4) the longer or shorter it will take for onset?
Longer onset
What does absorption of anesthetic mainly depend on and what can slow its absorption?
Vascular supply
Vasoconstrictor
This determines the DURATION of the anesthetic?
Protein binding
Why does Bupivicaine last longer thatn Lidocaine?
Bupivicaine has higher protein binding
What determines the anesthetic’s toxicity and potency?
Lipid solubility
What is key for the 2-3 mm of topical anesthetic tissue penetration?
Tissue must be dry
Which is more toxic: local or topical?
Topicl
What is the maximum dose of articaine?
7mg/kg
What is the percentage of Articaine in the local anesthetic?
4%
How many mg of 4% Articaine are in a 1.7 ml vial?
40mg x1.8mL = 72mg Articaine/1.8 mL carpule
What is a peculiarity of Articaine that allows it to be metabolized in liver and plasma?
Amide (liver metabolism) w/ ester side chain (plasma metabolism). Gives short half life
How much 1:100k epi is in a 1.8ml carpule?
0.01 mg/mL x 1.8mL = 0.018 mg/1.8mL carpule
How much 1:100K Epi is in a 1.7 mL carpule?
0.01mg/mL x 1.7mL = 0.017 mg/1.7 mL carpule
If Epi is 1:50K, is there more or less Epi in the carpule than a 1:100K
More, double the 1:100kconcentration
If Epi is 1:200K, is there more or less Epi in the carpule than 1:100K?
Less, half the 1:100k concentration
How convert Lbs to Kg?
Divide lbs by 2.2
What are the sSteps to determine max dose/max # carpules for child based on weight?
Know mg/g for local (Articaine 7mg/kg; Lido 4.4mg/kg)
Determine wt in Kg
Calculate max dose for that Kg weight
Calculate total number of carpules to get the dose
1 kg = how many pounds?
.454 lbs
Every 11 lbs = how many kg?
5kg
What is the maximum dose of 2% Lidocaine?
4.4 mg/kg
What is the maximum dose of 4% Septocaine?
7 mg/Kg
What is a shortcut for the pediatric clinic that helps avoid overdosing on local?
1 carpule 2% lido for every 20 lbs
What are 2 causes of Local anesthetic overdose?
Intravascular injection causing rapid uptake Excessive dose delivered
CNS depression (disoriented, seizures, loss of consciousness, respiratory arrest) is a sign of what?
Local overdose, can happen during injection or w/in 5-10 min
What are the cardiovascular effects of a local anesthesia overdose?
Initial HR and BP increase, followed by vasodilation and HR and BP decrease
Slurred speech, shivering, muscle twitching, dizziness/lightheadedness, drowsiness, warm, flushed feeling are signs of what and can be monitored how?
Local anesthesia overdose. Communicate with patient during and immediately post injection
What is the acute treatment for Local Anesthesia overdose?
Postpone planned treatment
Admin supplemental oxygen
Monitor BP and HR
Trendelenburg position (Feet elevated above head and heart)
The potential for toxic reactions increases when local is used in conjunction with what?
Sedative medications
If pt has a sulfite allergy, consider using what?
Plain 3% Mepivicaine
What is the cause of sulfites in local anesthesia?
Epi has a bisulfate preservative
Is it likely patient has a true allergy?
No, more likely an adverse reaction
