Recommended Dosing for Lignocaine (Lidocaine) Infusion in Adults
For adult patients requiring intravenous lidocaine infusion, the recommended dosing is a loading dose of 1.5 mg/kg given over 10 minutes, followed by a maintenance infusion of 1.5 mg/kg/h, with a maximum duration of 24 hours. 1
Detailed Dosing Protocol
Initial Loading Dose
- Loading dose: 1.5 mg/kg administered over 10 minutes
- Must be given with an anesthetist present
- Should be completed before skin incision if used perioperatively
- Monitoring requirements during loading dose:
- Continuous ECG
- Pulse oximetry
- Blood pressure every 5 minutes during initial infusion and for first 15 minutes thereafter
Maintenance Infusion
- Standard infusion rate: 1.5 mg/kg/h
- Maximum duration: 24 hours
- If extended beyond 24 hours (rare cases), reduce rate to 50% and obtain consultant approval
Administration Requirements
Equipment
- Dedicated infusion device that is:
- Labeled
- Lockable and tamper-proof
- Adjustable with fixed rate and upper limit settings
- Equipped with anti-siphon and anti-reflux mechanisms
- Separate dedicated cannula
- Minimum flow of sodium chloride 0.9% at 10 ml/h from a dedicated fluid bag
- One-way valve to prevent retrograde flow
- ISO-standard grey "lidocaine" label on the infusion line
- Separate lidocaine monitoring chart
Monitoring
- Outside operating theater/recovery room:
- Ideally in a monitored bedspace (high dependency unit)
- Observations every 15 minutes for first hour, then hourly
- Continuous ECG monitoring
- Trained staff who can recognize signs of toxicity
Safety Considerations
Maximum Safe Doses
- With epinephrine: Maximum 7 mg/kg (not to exceed 500 mg total)
- Without epinephrine: Maximum 4.5 mg/kg (not to exceed 300 mg total) 2
Toxicity Warning Signs
- Early neurological symptoms (most important to monitor):
- Perioral tingling
- Tinnitus
- Light-headedness
- Restlessness
- Cardiovascular signs are late manifestations
Contraindications and Precautions
- Use ideal body weight rather than actual body weight for dose calculations 3
- Patients weighing less than 40 kg are contraindicated for IV lidocaine infusions 3
- Reduce doses in elderly patients and those with liver or cardiac disease 2
- Avoid concurrent use of 5% lidocaine medicated plasters 1
Post-Infusion Considerations
- No nerve or fascial plane blocks should be performed until 4 hours after completion of infusion
- Boluses of local anesthetic must not be given into wound catheters or epidural catheters until 4 hours after completion
- Infusions (without boluses) through wound or epidural catheters may be started 30 minutes after the infusion has been stopped 1
Special Clinical Situations
Ventricular Tachycardia Management
For ventricular tachycardia, the British Journal of Sports Medicine recommends:
- Initial bolus: 50 mg IV over 2 minutes
- Repeat every 5 minutes to a total dose of 200 mg
- Start infusion at 2 mg/min 1
Bronchoscopy Procedures
For bronchoscopy, the British Thoracic Society recommends:
- Total dose should be limited to 8.2 mg/kg (approximately 29 ml of 2% solution for a 70 kg patient)
- Use minimum amount necessary when instilled through the bronchoscope
- Extra caution in elderly or those with liver or cardiac impairment 1
By following these guidelines, clinicians can safely administer intravenous lidocaine while minimizing the risk of toxicity and optimizing therapeutic benefits for patients requiring this intervention.