A Pilot Trial of Disposable Nitrous Oxide Canisters in Providing Pain Control During Burn Dressing Changes

A Pilot Randomized Controlled Crossover Trial of the Effectiveness of Disposable Nitrous Oxide Canisters in Providing Improved Pain Control During Burn Dressing Changes.

Improvements in burn care have resulted in increased survival. Despite these improved outcomes one of the leading challenges of burn care remains providing adequate analgesia during routine wound care and dressing changes. The traditional use of narcotics is challenging as the therapeutic window between analgesia and suppression of breathing becomes narrow with the intense pain and high doses of narcotics needed for dressing changes.

The normal challenges of using narcotics are increased in burn patients, who have significantly altered metabolism. Unfortunately, the use of regular general anesthesia or conscious sedation is not a viable option due to the resources required, and as the hypermetabolism of burn injury would result in compromised wound healing with repeated periods of without eating related halting of nutritional intake. This has led to the use of a number of adjuncts ranging from nonmedical (virtual reality, mindfulness, hypnosis etc.) to medication (ketamine, anxiolytics etc.). Historically Nitrous oxide has been used in similar settings where severe procedural pain is of relatively shorter duration, such as tooth extraction, labor or minor surgical procedures. Nitrous oxide is a rapidly acting analgesic that takes effect seconds after inhalation, and lasts minutes. While a randomized trial of Nitrous oxide in burn care has been proposed, the only published information currently available is in a Chinese medical journal.

To address this a gap in knowledge, a pilot Randomized Controlled trial is proposed to evaluate if Nitrous Oxide in the form of limited dose inhaler canisters can be used to improve pain control during burn dressing changes compared to placebo canisters.

Inclusion criteria

• adult burn patients admitted to the Health Sciences Centre
• total body surface area burned of 5-20%

Exclusion criteria

• admitted to intensive care unit
• unable to participate in the measurement outcomes (sedated, cognitively impaired, unable to understand English or visually impaired)
• medical condition that precludes using nitrous oxide (respiratory disease and significant cardiovascular disease 5).
• pregnant
• physically unable to hold the canister
• <90% SaO2 on room air
• face burn
• pre-injury narcotics (relative exclusion)
• use of IV ketamine
• pre-existing lung injury