Lidocaine

General

• Type: Local anesthetics; Antiarrhythmics
• Dosage Forms:
• Common Trade Names:

Maximum Doses of Anesthetic Agents

Agent	Without Epinephrine	With Epinephrine	Duration	Notes
Lidocaine	5 mg/kg (max 300mg)	7 mg/kg (max 500mg)	30-90 min	1% soln contains 10 mg/ml 2% soln contains 20 mg/ml
Mepivicaine	7 mg/kg	8 mg/kg
Bupivicaine	2.5 mg/kg (max 175mg)	3 mg/kg (max 225mg)	6-8 hr	0.5% soln contains 5 mg/ml May cause cardiac arrest if injected intravascularly Do not buffer with bicarbonate
Ropivacaine	3 mg/kg
Prilocaine	6 mg/kg
Tetracaine	1 mg/kg	1.5 mg/kg	3hrs (10hrs with epi)
Procaine	7 mg/kg	10 mg/kg	30min (90min with epi)

Special Populations

• Pregnancy Rating:
• Lactation:
• Renal Dosing
  • Adult
  • Pediatric
• Hepatic Dosing
  • Adult
  • Pediatric

Contraindications

• Allergy to class/drug

Pharmacology

• Half-life:
• Metabolism:
• Excretion:
• Mechanism of Action:

See Also

• Local Anesthetic Systemic Toxicity (LAST)

Anesthetic

Precautions

• For wounds, may use HCO3 (1cc to 10cc Lido) to decr pain
• inject through wound edges NOT intact skin

Maximum Doses of Anesthetic Agents

Agent	Without Epinephrine	With Epinephrine	Duration	Notes
Lidocaine	5 mg/kg (max 300mg)	7 mg/kg (max 500mg)	30-90 min	1% soln contains 10 mg/ml 2% soln contains 20 mg/ml
Mepivicaine	7 mg/kg	8 mg/kg
Bupivicaine	2.5 mg/kg (max 175mg)	3 mg/kg (max 225mg)	6-8 hr	0.5% soln contains 5 mg/ml May cause cardiac arrest if injected intravascularly Do not buffer with bicarbonate
Ropivacaine	3 mg/kg
Prilocaine	6 mg/kg
Tetracaine	1 mg/kg	1.5 mg/kg	3hrs (10hrs with epi)
Procaine	7 mg/kg	10 mg/kg	30min (90min with epi)

Antiarrhythmic

Adult Dosing

• Loading dose = 1-1.5 mg/kg
  • Additional boluses of 0.5-0.75 mg/kg q5-10min up to max of 3mg/kg
  • If effective start infusion of 2mg/min

Contraindications

• High SA or AV block

Indications

• Treatment of ventricular arrhythmias and ectopy
  • Considered 2nd-line to amiodarone for tx of V-fib and pulseless v-tach

Mechanism of Action

• Class Ib
  • Binds to fast Na channels in inactive state thereby inhibiting recovery after repolarization
  • Acts preferentially on ischemic tissue
    • Elevates V-fib threshold
    • Suppresses ventricular ectopy
• Little effect on vascular tone, contractility or cardiac output

Kinetics

• Onset of action = 45-90s
• Duration of action = 10-20min

See Also

• Critical care quick reference

Toxicity

Diagnosis

Symptoms:

1. CV
   1. (brady/arrest)
      1. Tx w/ epi per ACLS
2. CNS
   1. lightheaded, ringing in ears
   2. Seizure
   3. Abrupt change in MS, drowsiness, confusion

See Also: Local Anesthetic Systemic Toxicity (LAST)