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

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.