Paramedic Drug Facts: Lidocaine

Lidocaine

Trade Name: Lidoderm, Xylocaine, Anecream, Reticare

Class: Antidysrhythmic (Class 1B), Local anesthetic
Pharmacology:

Onset – 30-90 sec
Duration – 10-20 min

Decreases phase 4 diastolic depolarization (which decreases automaticity) and has been shown to be effective in suppressing premature ventricular complexes. In addition lidocaine is used as an alternative to amiodarone to treat cardiac arrest from VT or VF. Lidocaine also raises the ventricular fibrillation threshold

Indications:
  • Cardiac arrest from VF or VT
  • Stable monomorphic VT with preserve ventricular function
  • Stable polymorphic VT with normal baseline Q-T and preserved LV function after correction of ischemia and electrolyte balance
  • Wide-complex tachycardia of uncertain origin
  • Significant ventricular ectopy in the setting of myocardial ischemia/infarction
Contraindications:
  • Prophylactic use in AMI
  • Hypersensitivity
  • Stokes-Adams syndrome
  • 2nd or 3rd degree heart block in the absence of an artificial pacemaker
Cautions:
  • Metabolic clearance of lidocaine may be decreased in patients taking beta- adrenergic blockers or in patients with decreased cardiac output or liver dysfunction
  • Apnea induced with succinylcholine may be prolonged with large doses of lidocaine
  • Cardiac depression may occur if lidocaine is given concomitantly with IV phenytoin
  • Additive neurological effects may occur with procainamide and tocainide
Packaging: 
  • Pre-filled syringes: 100 mg in 5 mL of solution; 1 and 2 g additive syringes available
  • Ampules: 100 mg in 5 mL of solution; 1 and 2 g vials in 30 mL of solution; 5 mL containing 100 mg/mL

Lidocaine Administration

Cardiac Arrest from VF and VT

  • Adult: 1-1.15 mg/kg IV/IO bolus or ET tube (at 2-2.5 times the IV dose); for refractory VF, may give additional 0.5-0.75 mg/kg IV push; repeat in 5-10 min; max 3 doses or 3 mg/kg
  • Pediatric: 1 mg/kg IV/IO loading dose; ET dose: 2-3 mg/kg

Perfusing dysrhythmias (Stable VT; Wide complex tachycardia of uncertain type; significant ectopy)

  • Adult: Doses may range from 0.5-0.75 mg/kg (up to 1-1.15 mg/kg) repeat 0.5-0.75 mg/kg every 5-10 min; max total dose 3 mg/kg
  • Pediatric: 1 mg/kg IV/IO; ET dose is 2-3 mg/kg

Maintenance infusion after resuscitation from cardiac arrest from VT/VF

  • Adult: 1-4 mg/min (30-50 mcg/kg/min); reduce maintenance dose in presence of impaired liver function or LV dysfunction
  • Pediatric: 20-50 mcg/kg/min IV/IO; repeat bolus dose if infusion initiated >15 min after initial bolus therapy

Rapid Sequence Intubation: 1-2 mg/kg IV/IO (max 100 mg)

Lidocaine Side Effects

  • Light-headedness
  • Confusion
  • Blurred vision
  • Hypotension
  • Bradycardia
  • Cardiovascular collapse
  • Altered level of consciousness, irritability, muscle twitching, seizures w/ high doses
  • Headache

Special Considerations

Pregnancy Safety – Category B
A 75-100 mg bolus will maintain adequate blood levels for only 20 min
If bradycardia occurs along with premature ventricular contractions, always treat the bradycardia 1st with atropine
Discontinue infusion immediately if signs of toxicity develop
Exceedingly high doses of lidocaine can result in coma or death
Decrease dose in elderly
Avoid lidocaine for reperfusion dysrhythmias following fibrinolytic therapy
Use extreme caution in patients with hepatic disease, heart failure, marked hypoxia, severe respiratory depression, hypovolemia or shock, incomplete heart block, or bradycardia and A-fib