What is the treatment for local lidocaine (a local anesthetic) overdose?

From the Guidelines

The treatment for local lidocaine overdose should prioritize supportive care, symptom management, and the administration of lipid emulsion therapy in severe cases, as recommended by the most recent guidelines 1. The management of local lidocaine overdose involves several key steps:

• Immediately stopping the administration of lidocaine and assessing the patient's airway, breathing, and circulation
• Administering benzodiazepines, such as diazepam (5-10 mg IV) or midazolam (2-5 mg IV), for seizures
• Treating cardiac arrhythmias with amiodarone (150 mg IV over 10 minutes) or lidocaine (paradoxically, 1-1.5 mg/kg IV if the toxicity is from bupivacaine)
• Managing hypotension with IV fluids and vasopressors like norepinephrine (starting at 0.1-0.5 mcg/kg/min) as needed
• Considering lipid emulsion therapy (20% intralipid) for severe cases with cardiovascular collapse, as a 1.5 mL/kg bolus followed by 0.25 mL/kg/min infusion for 30-60 minutes, as supported by recent guidelines 1 The use of lipid emulsion therapy is particularly recommended for patients with premonitory neurotoxicity or cardiac arrest due to bupivacaine toxicity, and it should be readily available wherever intravenous lidocaine is used 1. Continuous cardiac monitoring is essential, and patients with significant toxicity should be observed for at least 4-6 hours after symptoms resolve, as lidocaine's metabolites can also cause toxicity. It is crucial to follow the most recent guidelines and consensus statements, such as those from the American Heart Association 1 and the Association of Anaesthetists 1, to ensure optimal management of local lidocaine overdose.

From the FDA Drug Label

OVERDOSAGE Acute emergencies from local anesthetics are generally related to high plasma levels encountered during therapeutic use of local anesthetics or to unintended subarachnoid injection of local anesthetic solution Management of local anesthetic emergencies: The first consideration is prevention, best accomplished by careful and constant monitoring of cardiovascular and respiratory vital signs and the patient's state of consciousness after each local anesthetic injection. At the first sign of change, oxygen should be administered The first step in the management of convulsions consists of immediate attention to the maintenance of a patent airway and assisted or controlled ventilation with oxygen and a delivery system capable of permitting immediate positive airway pressure by mask Immediately after the institution of these ventilatory measures, the adequacy of the circulation should be evaluated, keeping in mind that drugs used to treat convulsions sometimes depress the circulation when administered intravenously Should convulsions persist despite adequate respiratory support, and if the status of the circulation permits, small increments of an ultra-short acting barbiturate (such as thiopental or thiamylal) or a benzodiazepine (such as diazepam) may be administered intravenously. Supportive treatment of circulatory depression may require administration of intravenous fluids and, when appropriate, a vasopressor as directed by the clinical situation (e.g., ephedrine).

The treatment for local lidocaine overdose involves:

• Prevention through careful monitoring of cardiovascular and respiratory vital signs
• Administration of oxygen at the first sign of change
• Maintenance of a patent airway and assisted or controlled ventilation with oxygen
• Evaluation of circulation and administration of intravenous fluids and vasopressors as needed
• Use of ultra-short acting barbiturates or benzodiazepines to treat persistent convulsions 2

From the Research

Treatment for Local Lidocaine Overdose

• The treatment for local lidocaine overdose involves prompt recognition and management of systemic toxicity, which can lead to disastrous complications including cardiac toxicity and arrest 3.
• Lipid emulsion therapy has been shown to be effective in treating local anesthetic systemic toxicity (LAST) 3, 4, 5.
• The use of intravenous lipid emulsion (ILE) has become established in clinical practice as a treatment for acute local anesthetic toxicity, although evidence of efficacy is limited to animal studies and human case reports 4.
• In cases of severe local anesthetic toxicity, ILE appears to be effective for reversal of cardiovascular or neurological features, but there is currently no convincing evidence showing that ILE is more effective than vasopressors or to indicate which treatment should be instituted as first line therapy 4.
• Treatment with thiopental has been reported to be not very impressive in cases of lidocaine-induced CNS intoxication 6.
• Supportive therapy, including diazepam for seizures, intubation, and chronotropic agents, is used to manage acute lidocaine toxicity 7.
• Prevention of LAST is critical, and knowledge of proper lidocaine dosage can prevent LAST 3.

Key Considerations

• Lidocaine-induced CNS toxicity can manifest as psychotic reaction, characterized by headache, tinnitus, visual and auditory disturbances, muscle twitching, and hallucinations 6.
• Neurotoxic manifestations of lidocaine toxicity can appear at lower concentrations than cardiotoxic symptoms, which are correlated with plasma levels of lidocaine 7.
• The toxic symptoms of lidocaine toxicity can persist even after the decrease of lidocaine concentration under therapeutic levels 7.