Oral Surgery Flashcards
Is the trigeminal nerve a motor or sensory nerve?
Both
What does an infraorbital nerve block affect?
Maxillary anterior teeth
What are the three divisions of the trigeminal nerve?
Ophthalmic division (1) Maxillary division (2) Mandibular division (3)
What are all local anesthetics comprised of?
1) lipophilic aromatic ring linked to
2) hydrophilic amino group
What determines the classification of a local anesthetic?
The type of bond (either ester or amide bond)
What are the three types of amide local anesthetics? What metabolizes them and where?
1) lidocaine
2) mepivacaine
3) bupivacaine
Metabolized by p450 enzymes of the liver
What are 4 types of ester local anesthetics? What metabolizes them and where?
1) novacaine
2) procaine
3) benzocaine
4) tetracaine
Metabolized by pseudocholinesterase in the plasma
Why do we add epinephrine to local anesthetic?
It is a vasoconstrictor so it decreases the rate of absorption. This:
1) increases duration of action
2) decreases systemic toxicity
3) helps with hemostasis
What is the significance of an infection on local anesthesia?
Infection causes tissue to become acidic. This promotes increase in ionized form of LA vs the unionized form. The ionized form does not pass as easily through the nerve membrane
What can you add to local anesthesia to decrease pain upon infiltration and increase effectiveness?
Sodium bicarbonate (alkaline)
Excessive doses of benzocaine, prilocaine, or lidocaine cause hemoglobin to be oxidized into what form? Why is this bad?
Methemoglobin. It can’t carry oxygen
What is the most common adverse effect of excessive local anesthetic?
Seizures
What is an ASA classification of 4 mean?
Patient with systemic disease that is a constant threat to life
What is an ASA classification of 2?
Patient with a mild systemic disease
What is an ASA classification of 5?
Morbidund patient who is not expected to survive without the operation
