What is a standard postoperative lidocaine (local anesthetic) infusion dose?

From the Guidelines

A standard postoperative lidocaine infusion dose is recommended to be no more than 1.5 mg/kg/h, with a loading dose of no more than 1.5 mg/kg given over 10 minutes, and the infusion should not exceed 24 hours. This recommendation is based on the most recent and highest quality study available, which emphasizes the importance of careful dosing to minimize the risk of toxicity 1. The use of intravenous lidocaine for postoperative pain management has been shown to be effective in reducing pain and improving recovery, but it is crucial to follow strict guidelines to ensure safety 1.

Key Considerations for Lidocaine Infusion

• The infusion should be administered through a dedicated IV line using an infusion pump for precise dosing.
• Patients receiving lidocaine infusions require monitoring for signs of toxicity, including perioral numbness, metallic taste, tinnitus, visual disturbances, confusion, seizures, or cardiac arrhythmias.
• Dose adjustments are necessary for elderly patients, those with hepatic or cardiac dysfunction, and patients weighing less than 50 kg.
• Ideal body weight should be used for dose calculation, and the infusion rate should not exceed 120 mg/h.

Administration and Monitoring

• A suitable infusion device should be used, with pumps being dedicated, labeled, lockable, and tamperproof, and adjustable so that both a fixed rate and fixed upper rate limit can be set 1.
• Commercially prepared syringes and/or bags of lidocaine may reduce the risk of errors in concentration.
• A standard concentration and/or formulation should be used throughout the hospital, and specified in the standard operating procedure.

Safety and Efficacy

• Intravenous lidocaine should not be used at the same time as, or within the period of action of, other local anesthetic interventions 1.
• The risk-benefit ratio of intravenous lidocaine varies with the type of surgery and patient factors, such as comorbidity, including pre-existing chronic pain 1.
• Lidocaine infusions work by blocking sodium channels in neural membranes, reducing nociceptive transmission and providing analgesic effects, while also offering anti-inflammatory properties that help decrease postoperative pain and potentially reduce opioid requirements.

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 standard postoperative lidocaine infusion dose is not explicitly stated in the drug label. However, the maximum recommended dose is 4.5 mg/kg (2 mg/lb) body weight, and the dose should be kept below 300 mg.

• The dose should be adjusted based on the patient's weight and health status.
• The label recommends using the lowest dosage needed to provide effective anesthesia 2.

From the Research

Standard Postoperative Lidocaine Infusion Dose

• The optimal dosing of lidocaine is not known, but a general consensus indicates that a loading dose of 1-2 mg/kg, followed by 1-2 mg/kg/hr continuous infusion, can achieve therapeutic levels of 0.5-5 mcg/kg and improve analgesia in the immediate postoperative period 3.
• The application scheme of systemic lidocaine varies between studies, with doses ranging from 1 mg/kg/h to 5 mg/kg/h and infusion termination ranging from the end of surgery to several days after 4.
• A systematic review and meta-analysis found that perioperative intravenous lidocaine infusion was associated with significantly reduced visual analog pain scores at 2,4-6,24, and 48 hours postoperatively, with a dose of 1-2 mg/kg/hr commonly used 5.

Considerations for Lidocaine Infusion

• The quality of evidence for the optimal dose and timing of lidocaine infusion is limited due to inconsistency, imprecision, and study quality 4, 6.
• Lidocaine infusion has been shown to be effective in reducing postoperative pain, opioid consumption, and hospital length of stay, but the optimal dose and duration of infusion remain unclear 4, 6, 5.
• Nurses should be educated on the pharmacology of intravenous lidocaine for pain management and develop protocols and educational content for managing intravenous lidocaine infusions in the postoperative period 7.