What is the role of topical lidocaine in managing burn pain?

Topical Lidocaine for Burn Pain Management

Topical lidocaine cream (5%) provides significant pain relief for partial-thickness burns when applied at 1 mg/cm² without systemic toxicity, making it a valuable option for burn pain management, though evidence remains limited to small studies. 1

Evidence for Topical Lidocaine in Burns

Efficacy Data

• A 1989 study demonstrated that 5% lidocaine cream applied to partial-thickness burns (up to 28% TBSA) provided significant pain relief with plasma levels remaining safe (maximum 5.8 μg/ml), well below toxic thresholds. 1

• Pain reduction was sustained throughout a 4-hour observation period with no infectious, allergic, or cardiovascular complications observed. 1

• The analgesic effect was measured using Visual Analog Scale scores, showing clinically meaningful pain reduction 30 minutes after application. 1

Application Protocol

• Apply 5% lidocaine cream at a concentration of 1 mg/cm² to the burn wound surface. 1

• Systemic analgesics should be administered 30 minutes before lidocaine application for optimal pain control. 1

• For debridement procedures, EMLA cream (lidocaine-prilocaine combination) can be applied to 25 cm² burn areas for 30 minutes, achieving satisfactory analgesia with median VAS scores of 11/100. 2

Safety Considerations

• Peak plasma concentrations occur 15-60 minutes after application, with lidocaine levels averaging 205 ng/ml and prilocaine 97 ng/ml—far below toxic thresholds. 2

• Bioavailability through burned skin is estimated at 5-30% of the applied dose, indicating predictable absorption. 2

• Maximum treated area in published studies was 28% TBSA with 4.5 grams of lidocaine without adverse effects. 1

Limitations of Intravenous Lidocaine

• Intravenous lidocaine for burn pain shows minimal clinical benefit compared to placebo, with only marginally lower pain scores and no significant reduction in opioid consumption. 3, 4

• A 2014 Cochrane review concluded that intravenous lidocaine remains an investigational agent in burn care with insufficient evidence to support routine use. 4

Integration with Multimodal Analgesia

• Topical lidocaine should be incorporated into a multimodal analgesic approach that includes cooling the burn site, appropriate dressings, and titrated opioids or ketamine for procedural pain. 5

• Cooling the burn can reduce pain and limit burn depth progression by affecting the inflammatory cascade. 5

• Short-acting opioids and ketamine remain the mainstay for severe burn-induced pain and procedural interventions. 5

Clinical Application Algorithm

For partial-thickness burns requiring pain control:

1. Apply 5% lidocaine cream at 1 mg/cm² to burn surface 1
2. Administer systemic analgesics 30 minutes before topical application 1
3. Reassess pain 30 minutes after lidocaine application using validated scales 1
4. For debridement procedures, consider EMLA cream applied 30 minutes prior 2
5. Combine with cooling and appropriate wound dressings for enhanced pain control 5

Important Caveats

• Evidence is limited to small studies from 1989 and 2017, with no large randomized trials specifically evaluating topical lidocaine for burns. 1, 2

• Do not confuse topical lidocaine (which shows benefit) with intravenous lidocaine (which lacks evidence for burn pain). 3, 4

• Monitor for signs of local anesthetic toxicity when treating large surface areas, though absorption appears predictable and safe within studied parameters. 1, 2