Anesthetics lecture

Question 1

ester-linked anesthetics

Answer 1

procaine, tetracaine, cocaïne

all metabolized by pseudochonlinesterase locally by tissue/plasma. eliminated in kidney

Question 2

amide-linked local anesthetics

Answer 2

lidocaine, prilocaine, bupivicaine, articaine
P450 metabolism in liver, also lungs.
Longer DOA than ester-based. kidney elimination

Question 3

procaine

Answer 3

ester-based local anesthetic. short-acting, low hydrophobicity, low potency.
uses: dental procedures, infiltration anesthesia
Rapidly metabolized in plasma by cholinesterase’s.
-one metabolite is PABA (some patients have an allergic response, interacts with sulfonamide antibiotics and decreases effectiveness)

Question 4

tetracaine

Answer 4

ester-based local anesthetic. long-acting, high hydrophobicity, high potency.
Used in spinal and topical anesthesia.
Metabolized by cholinesterases in plasma
Slower effect than procaine because its released slower into bloodstream (longer 1/2 life)

Question 5

cocaine

Answer 5

only naturally-occuring ester-based local anesthetic. Opthalmic and topical anesthesia.
-Medium potency and DOA
-inhibits catecholamine uptake (stops NET transport peripherally and centrally).
causes vasoconstriction/euphoria (=cardiac toxicity)

Question 6

lidocaine

prilocaine

Answer 6

most commonly used amide-based anesthetics
moderate hydrophobicity, large fraction of rug is neutral at physiologic pH= rapid onset, medium DOA, moderately potent.
-metabolized in liver by P450.
Uses: infiltration, peripheral nerve block, epidural, spinal/topical anesthesia
Toxicities: CNS depression, cardiotoxicity

Question 7

prilocaine

Answer 7

amide-based anesthetic. causes vasoconstriction (like cocaine)

Question 8

lidocaine

Answer 8

amide-based anesthetic. Class-1 antiarrhythmic. Blocks Na+ channels in myocytes, slows metabolism

Question 9

Articaine

Answer 9

amide-based local anesthetic that also exhibits an ester group.
Partially metabolized by p450 in liver
partially metabolized by cholinesterases in plasma

Question 10

Bupivicaine

Answer 10

amide-based local anesthetic (high hydrophobicity, high potency. long DOA)
metabolized by P450 in the liver.
R and S enantiomers (S is less toxic form).
-causes Cardiac toxicity b/c you’re blocking sodium channels in myocytes during systole, but slow to dissociate during diastole => induces tachyarrhythmias or conduction blocks
- used in labor for pain relief w/o significant motor block