What is the recommended dose of Lidocaine (lignocaine) for intravenous infusion for analgesia?

From the Guidelines

For analgesia, lignocaine (lidocaine) infusion is typically administered at 1-2 mg/kg/hr after an initial loading dose of 1-1.5 mg/kg given over 10-15 minutes, as recommended by recent consensus statements 1. The dosing regimen is crucial for minimizing the risk of toxicity while maximizing analgesic efficacy.

• The maximum recommended duration is usually 24-48 hours, with a maximum daily dose not exceeding 3 grams, to avoid accumulation and potential toxicity.
• Continuous cardiac monitoring is essential during administration due to potential cardiovascular effects, as lignocaine can affect cardiac conduction and rhythm.
• Before starting, ensure the patient has normal liver function, as lignocaine is metabolized hepatically, and dose adjustments may be necessary in patients with hepatic impairment. The mechanism of action of lignocaine involves sodium channel blockade in nociceptive pathways, reducing neuronal excitability and pain transmission, which is supported by studies on its anti-nociceptive, anti-hyperalgesic, and anti-inflammatory effects 1.
• Common side effects to monitor include perioral numbness, dizziness, tinnitus, and visual disturbances, which may indicate early toxicity, and require prompt dose adjustment or discontinuation.
• Reduce the dose in elderly patients, those with cardiac or hepatic dysfunction, or patients on beta-blockers, as these populations are at higher risk of toxicity and adverse effects.
• Lignocaine infusion should be avoided in patients with severe heart block, Wolff-Parkinson-White syndrome, or known hypersensitivity to amide local anesthetics, due to the potential for severe cardiovascular complications.

From the FDA Drug Label

The lowest dosage needed to provide effective anesthesia should be administered. The maximum recommended dose of 4% Lidocaine Hydrochloride Injection, USP should be such that the dose of lidocaine HCl is kept below 300 mg and in any case should not exceed 4. 5 mg/kg (2 mg/lb) body weight.

The FDA drug label does not answer the question.

From the Research

Lignocaine Dose for Infusion for Analgesia

• The recommended dose of lignocaine for infusion is not explicitly stated in the provided studies, but a study on the effect of peri-operative intravenous infusion of lignocaine on haemodynamic responses to intubation, extubation, and post-operative analgesia used a bolus dose of 1.5 mg/kg followed by an infusion at a rate of 1.5 mg/kg/h 2.
• Another study compared the efficacy of lignocaine, ropivacaine, and bupivacaine in pain control during extraction of mandibular posterior teeth, but it did not provide information on the dose of lignocaine for infusion 3.
• A study on the dosage of dilute lignocaine for the infiltration technique of local analgesia recommended a maximum dose of 500 mg for plain lignocaine and 670 mg with adrenaline, but this is for infiltration technique, not for infusion 4.
• There is no direct information on the dose of lignocaine for infusion for analgesia, but the available studies suggest that lignocaine can be used for post-operative analgesia and that the dose should be carefully considered to avoid toxicity 2, 5.

Considerations for Lignocaine Infusion

• The dose of lignocaine for infusion should be carefully considered to avoid toxicity, and the patient's response to the infusion should be closely monitored 2, 5.
• Lignocaine can be used in combination with other medications, such as opioids, to enhance its analgesic effects 5.
• The use of lignocaine for infusion may have benefits, such as reducing haemodynamic responses to intubation and extubation, and providing post-operative analgesia 2.

Comparison with Other Local Anesthetics

• Ropivacaine and bupivacaine are also used for regional anesthesia and have been compared to lignocaine in terms of their efficacy and safety 3, 5, 6.
• Ropivacaine has been shown to have a lower propensity for motor block and cardiotoxicity compared to bupivacaine, but its efficacy is similar to that of bupivacaine 5.
• Vitamin C has been shown to reduce the adverse effects of local anesthetics, including ropivacaine, bupivacaine, and lidocaine, on human chondrocytes 6.