L213 Local Anesthetics Flashcards
Three important components of local anesthetics
Aromatic group
Ester/amid linkage
Amine group
Purpose of aromatic group
Lipophilic group
Ester vs Amide
Ester: hydrolyzed by pseudochilinesterase, Short life
Amide: P450 in liver, Long life, favored in dentistry
Local anesthetic acid and base
Basic form crosses cell membranes
Acidic form binds to Na channel to inhibit conduction
Structure of nerve
Fiber Endoneurium Fasicle Perineurium Epineurium
Type A nerves
alpha: Somatic motor, proprioception
Beta: Touch pressure
Gamma: Motor to muscle spindles
Delta: Pain, Cold Touch
Type B nerves
Preganglionic sympathetic
Type C nerves
Slow pain, HOT, postganglionlic sympathetic
Which fibers are more readily disrupted by anesthetics
B and C fibers
Most sensitive to least sensitive
Pain Cold Warmth Touch Deep pressure
How are most anesthetics pepared
Water soluble HCl Salt
pH 6-7
Anesthetic effects on heart
Block cardiac Na channels in low concentration
Block cardiac Ca channels in high concentration
Local anesthetics bind to
alpha1 glycoprotein albumin
Categories of drugs
A: No risk
B: No Human risk, but in Animal OR No human studies, but no in animal
C: No studies: May warrant use
D:
