Local Anesthetics Flashcards
Lidocaine: Class
Amide
Lidocaine: Use
Topic Anesthesia
Local infiltration
Neuraxial Anesthesia
Lidocaine: Mechanism of Action
Reversibly block voltage-gated sodium channels in neurons
Lidocaine: Dose
Plain:
Max = 5 mg/kg or 350mg
With Epinephrine:
Max = 7mg/kg or 500mg
IV: 1-2 mg/kg
Lidocaine: Pharmacokinetics
Onset: Fast
Duration of Action: 90-120 minutes
Metabolism: In the liver via CYP1A2 and CYP3A4
Excretion: Kidneys
Lidocaine Absorption
Systemic absorption depends on vascularity of the area. More vascular = higher blood concentrations
Lidocaine : Contraindications/ Considerations
Newborns and elderly have prolonged 1/2 lives
Amide Local Anesthetic –> Metabolism in liver, risk for accumulation in liver failure
Propranolol and Cimetidine can inhibit hepatic blood flow and increase accumulation
Risk for LAST
Bupivacaine: Class
Amide
Bupivacaine : Use
Topic Anesthesia
Local infiltration
Neuraxial Anesthesia
Bupivacaine: Mechanism of Action
Reversibly block voltage-gated sodium channels in neurons
Bupivacaine: Dose
Plain:
2mg/kg or 175mg
With Epinephrine:
3mg/kg or 225mg
Bupivacaine: Pharmacokinetics
Onset: Slow
Duration of Action: Long 180-600 minutes
Metabolism: Hepatic via CYP 1A2 and CYP 3A4
Excretion: Kidneys
Bupivacaine: Absorption
Systemic absorption depends on vascularity of the area. More vascular = higher blood concentrations
Bupivacaine: Contraindications and Considerations
High affinity for myocardial sodium channels, very high risk for cardiac toxicity
Prolonged 1/2 in Newborns and Elderly
Amide Local Anesthetic –> Metabolism in liver, risk for accumulation in liver failure
Propranolol and Cimetidine can inhibit hepatic blood flow and increase accumulation
Risk for LAST
Chloroprocaine: Class
Ester