Local anesthetics Flashcards
1
Q
Cocaine; benzocaine; procaine; tetracaine; chlorprocaine
A
- Ester anesthetic: binds reversibly to the intracellular portion of the voltage-gated sodium channel and inactivates it, and so blocks transmission of nociceptive nerve impulses
- Local anesthesia
- Side effects: Local: transient neurologic symptoms (basically, really bad pain), neuronal injury. Systemic (more common with long-acting local anesthetics): circumoral numbness, dizziness, tinnitis, blurred vision, CNS excitation (restlessness, agitation, seizures), followed by CNS depression (respiratory arrest, unconsciousness); hypotension; cardic toxicity with higher doses.
- Methemoglobinemia with benzocaine, allergic rxns
- Used less frequently than amides
2
Q
Lidocaine; mepivacaine; bupivacaine; ropivacaine
note the two i’s in each name
A
- Amide anesthetic: binds reversibly to the intracellular portion of the voltage-gated sodium channel and inactivates it, and so blocks transmission of nociceptive nerve impulses
- Local anesthesia
- Side effects: Local: transient neurologic symptoms (basically, really bad pain), neuronal injury. Systemic (more common with long-acting local anesthetics): circumoral numbness, dizziness, tinnitis, blurred vision, CNS excitation (restlessness, agitation, seizures), followed by CNS depression (respiratory arrest, unconsciousness); hypotension; cardic toxicity with higher doses.
- Bupivicaine has highest cardiac toxicity potential; ropivicaine less potent than others (so larger therapeutic index)