Can lidocaine be used for laryngoscopic surge suppression?

Lidocaine for Laryngoscopic Surge Suppression

Lidocaine can be used for laryngoscopic surge suppression, with intravenous administration being more effective than topical application for attenuating hemodynamic responses during airway instrumentation. 1, 2

Mechanism and Indications

• Lidocaine helps blunt the cardiovascular response (elevated blood pressure and heart rate), cough reflexes, and potential dysrhythmias associated with laryngoscopy and intubation 1
• FDA-approved for topical anesthesia of mucous membranes of the respiratory tract, including transtracheal injection to anesthetize the larynx and trachea 3
• Particularly beneficial in patients with atherosclerotic heart disease, potential intracranial lesions, or increased intracranial pressure 1

Administration Routes and Dosing

Intravenous Administration

• Recommended dose: 1-2 mg/kg IV as a single dose 30 seconds to 5 minutes before airway instrumentation 4
• Optimal timing is 3 minutes before intubation for maximum effect 1
• More effective than topical administration for suppressing cough (median 4 coughs vs. 20 coughs with topical) 5

Topical Administration

• For laryngoscopy and endotracheal intubation: 1-5 mL of 4% solution (40-200 mg) sprayed on the pharynx 3
• Maximum dose should not exceed 4.5 mg/kg (2 mg/lb) body weight in adults 3
• For children under 10 years: maximum dose should not exceed 4.5 mg/kg 3
• Inhalation of 120 mg lidocaine prior to induction effectively attenuates circulatory response to laryngoscopy and intubation 2

Efficacy Considerations

• Intravenous lidocaine is more effective than topical application for:
  • Suppressing cough reflexes 5
  • Preventing laryngospasm in healthy children with LMA 4
  • Reducing post-extubation laryngospasm in healthy children 4
• Topical lidocaine may help attenuate airway-circulatory reflexes in laryngeal microscopic surgery 6
• Inhalation of lidocaine shows a dose-dependent response in attenuating heart rate increases during intubation 2

Precautions and Limitations

• When using lidocaine for laryngoscopic surge suppression, consider total dose from all sources (regional anesthesia, injection pain prevention) to avoid local anesthetic toxicity 4
• Brief duration of effect suggests administration within 5 minutes before airway manipulation 4
• In children with upper respiratory infections, the evidence does not strongly support using lidocaine (IV or topical) to decrease perioperative respiratory adverse events 4
• Some studies report increased risk of desaturation, laryngospasm, and bronchospasm with topical lidocaine in children 4
• Plasma lidocaine concentrations may exceed potential toxicity levels after IV administration, though toxic symptoms are rare 5

Special Populations

• For patients with COVID-19 requiring intubation, periodical injection of 2% lidocaine (2-3 ml) or 1% lidocaine (4-6 ml) through the working channel can reduce irritation during airway manipulation 4
• In children, dosing should be calculated based on weight using standard pediatric drug formulas 3
• For children with increased risk of perioperative respiratory adverse events, IV lidocaine may reduce post-extubation laryngospasm 4