Anaesthesia - Topical wound

Key Points

• Topical anaesthetics in Laceraine® are useful for children with wounds requiring suturing or debridement.
• Vasoconstriction from adrenaline in Laceraine® can be useful for oozing wounds prior to closure with tissue glue.
• Laceraine Gel^® is only to be used in PCH ED. It is not for ward use.

Description

Laceraine^®2

Indications

• Topical use on broken skin.
• Local anaesthesia for wound management (cleaning, closure).
• Haemostasis.

Contraindications ^1,2

• Children < 1 year
• Do not use on digits, pinnae, tip of nose, penis, or other end arterial areas, don’t rub in with fingers or allow patients to do so
• Not for dental use or where entry into major blood vessels may occur.
• Not meant for use on intact skin - consider EMLA^® or Numit^®.
• Do not apply to mucous membranes, prevent the child from rubbing the area as they may transfer to these areas.
• Do not use on wounds >7 cm, bites, contaminated or complex wounds, burns, extensive abrasions.
• Do not use in patients with hypersensitivity to any local anaesthetic.
• Do not use on bites - animal or human²
• An increased risk of arrhythmias may occur in patients under therapy with cardiac glycosides, quinidine or tricyclic antidepressants.
• When a patient has been treated with monoamine oxidase inhibitors, they should not be treated with Laceraine® gel topical wound anaesthetic until at least 14 days after treatment has ceased.

Adverse reactions³ 

• Systemic toxicity is rare and invokes mainly central nervous system (CNS) (usually first) and cardiovascular system (CNS): restlessness, dizziness, tinnitus, nausea and vomiting, tremors, convulsions, CNS depression.
• Numbness of the tongue and perioral region may be an indicator of early systemic toxicity.
• Cardiac effects are myocardial depression and vasodilation.
• Contains sulphites (as sodium metabisulfate), may cause allergy in susceptible patients²

Dosage preparation²

• Use a syringe and draw up the required amount from the 4mL vial.
• Dose:
  • 1-3 years: 0.1mL/kg (maximum dose 2mL)
  • >3 years: 0.1mL/kg (maximum dose 3mL)
  • Note 0.1mL/kg = 4mg/kg of lidocaine.
• Maximum 4 doses of Laceraine® over 24 hours¹.
• For use in one patient on one occasion only and discard any unused gel.
  

Administration^2,3

• Clean wound, removing debris and clotted blood.
• Wearing gloves.
  • Directly apply the gel onto the wound and wound margins
  • A cotton-tipped applicator can be used
  • Cover with an occlusive dressing (Tegaderm™ / Opsite ™). Use of gauze or island wound dressings is not recommended.
  • If applying on the scalp, cotton balls and a crepe bandage maybe required
• Advise child / carer:
  • May sting on first application.
  • Not to interfere with site.
• Leave for 20-30 minutes (maximum 60 minutes)
  • Remove the occlusive dressing and clean or irrigate the wound of residual gel.
  • Test sensation prior to further treatment.
  • Blanching at edges is usual.
• Supplemental 1% lidocaine can be used intradermally as long as a total lidocaine does not exceed 5mg/kg
• Maximum additional lidocaine dose 1mg/kg = 0.1mL/kg of 1% lidocaine.

References

1. AMH Children’s Dosing Companion, Australian Medicines Handbook Pty Ltd,  [Internet] July 2021; Lidocaine, Tetracaine and Adrenaline
2. Laceraine® Gel Topical Wound Anaesthetic – Australian Product Information Version 2 Phebra August 2020
3. Hsu D. Clinical use of topical anaesthetics in children - UpToDate Mar 2020, Cited 7 December 2021. Available from: Clinical use of topical anaesthetics in children - UpToDate (health.wa.gov.au) (health.wa.gov.au)