Management of pain associated with debridement of leg ulcers: a randomized, multicentre, pilot study comparing nitrous oxide-oxygen mixture inhalation and lidocaïne-prilocaïne cream

J Eur Acad Dermatol Venereol. 2011 Feb;25(2):138-44. doi: 10.1111/j.1468-3083.2010.03720.x. Epub 2010 Jun 21.


Background: Mechanical debridement of fibrin and/or necrosis promotes healing of arterial and venous leg ulcers but is limited by pain associated with the procedure.

Objective: The main objective of this study was to compare the respective analgesic effect of nitrous oxide oxygen mixture (NOOM) inhalation and lidocaïne-prilocaïne cream (LPC) application during the mechanical repeated debridement of chronic arterial and venous leg ulcers.

Methods: In this randomized, multicentre, open-label study, pain was evaluated before and after each care and debridement session using a Visual Analog Scale (VAS) and a Verbal Rating Scale (VRS), in the context of usual debridement and wound care process. The Quality of debridement and tolerability of the treatments were also assessed.

Results: Forty-one patients were randomized: 20 received NOOM and 21 LPC. Pain assessed by VAS and VRS was more intense in the NOOM group than in the LPC group (5.29 vs. 3.68 and 2.87 vs. 1.71, P<0.001, for the two scales respectively). No differences were found concerning quality of debridement, safety or tolerability between the two groups.

Conclusion: This pilot study demonstrates the superiority of the LPC over NOOM for pain control during the mechanical debridement of chronic leg ulcers.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Inhalation
  • Administration, Topical
  • Aged
  • Aged, 80 and over
  • Analgesics, Non-Narcotic / administration & dosage
  • Analgesics, Non-Narcotic / adverse effects
  • Analgesics, Non-Narcotic / therapeutic use
  • Anesthetics, Local / administration & dosage
  • Anesthetics, Local / adverse effects
  • Anesthetics, Local / therapeutic use
  • Debridement / adverse effects*
  • Female
  • Humans
  • Leg Ulcer / therapy*
  • Lidocaine / administration & dosage
  • Lidocaine / adverse effects
  • Lidocaine / therapeutic use*
  • Male
  • Middle Aged
  • Nitrous Oxide / administration & dosage
  • Nitrous Oxide / adverse effects
  • Nitrous Oxide / therapeutic use*
  • Ointments
  • Oxygen / administration & dosage
  • Oxygen / adverse effects
  • Oxygen / therapeutic use*
  • Pain Management*
  • Pain Threshold
  • Pilot Projects
  • Prilocaine / administration & dosage
  • Prilocaine / adverse effects
  • Prilocaine / therapeutic use*
  • Prospective Studies
  • Treatment Outcome


  • Analgesics, Non-Narcotic
  • Anesthetics, Local
  • Ointments
  • Prilocaine
  • Lidocaine
  • Nitrous Oxide
  • Oxygen