Background
Burns are very common and sometimes fatal, and the pain associated with such injury is one of the most difficult types to relieve. The use of high-dose opioid medications like morphine is common, but side effects are encountered. Alternative agents such as lidocaine, an anaesthetic, have been proposed. This is an update of the review of the same name first published in 2007.
Study characteristics
We searched scientific databases for studies assessing the pain-relieving effects of intravenous (given into the blood stream through a vein) lidocaine in adults with a burn injury. We included studies comparing lidocaine with no treatment, placebo (a pretend treatment), other analgesics (pain killers), or a combination of these. We wanted to look at (for example) severity of pain, time to requiring more medication, rescue analgesia (where extra pain relief is needed in addition to that planned) and side effects. The evidence is current to December 2013.
Key results
We found one small clinical trial, involving only 45 participants, which showed a benefit from intravenous lidocaine for pain relief in people with burns. The trial did not show a difference in opioid use, participant anxiety or level of participant satisfaction with the use of intravenous lidocaine.
Quality of the evidence
The small included study provided insufficient data to draw any conclusions.
As current clinical evidence is based on only one RCT as well as case series and reports, intravenous lidocaine must be considered a pharmacological agent under investigation in burns care, the effectiveness of which is yet to be determined with further well-designed and conducted clinical trials.
This is an update of the review on "Lidocaine for pain relief in burn injured patients" first published in Issue 3, 2007, and first updated in 2012. Pain is a major issue for people with many different types of wounds, in particular those people with burn injuries. Prompt, aggressive use of opioid analgesics such as morphine has been suggested as critical to avert the cycle of pain and anxiety, but adverse effects are encountered. It has been proposed that newer agents such as lidocaine could be effective in reducing pain and alleviating the escalating opioid dosage requirements in people with burn injury.
To assess the safety and effectiveness of intravenous lidocaine as a means of pain relief versus no therapy, placebo, other drugs, or a combination of these therapies in people with burn injury.
For this third update, we searched the Cochrane Central Register of Controlled Trials (Issue 11, 2013), and Ovid MEDLINE, MEDLINE in Process and Ovid EMBASE (up to December 2013).
We included randomised controlled trials (RCTs) and controlled clinical trials (CCTs), published and unpublished, which assessed the efficacy of intravenous lidocaine in varying doses as a single-agent therapy with no therapy, placebo, other analgesics (such as opioids), lidocaine plus another drug, or a combination of these therapies as a means of pain relief in people with burn injury.
Two review authors independently abstracted data and assessed the risk of bias of the studies identified.
In this 2014 update, we found no new studies. The one small randomised double-blind placebo-controlled cross-over trial found in 2012, which included only 45 participants and compared intravenous lidocaine against placebo as a means of pain relief in people with burns still remains central to this review. We assessed this study as being at a high risk of bias due to its small size (fewer than 50 participants per treatment arm). Subjective pain ratings, as measured by the verbal rating scale, increased during procedures for both treatment arms; however, the increase was less in the lidocaine treatment group. There were no significant clinical or statistical differences regarding the effects of lidocaine and placebo on opioid requests and consumption, anxiety or level of satisfaction during a wound care procedure, but the small included study provided insufficient data to draw any conclusions.