Topical anaesthetics for repair of dermal laceration.

Background: Topical local anaesthetics are recognized as providing effective analgesia for numerous superficial procedures, including repair of dermal lacerations. The need for cocaine in topical anaesthetic formulations has been questioned due to concern about adverse effects, and so novel preparations of cocaine-free anaesthetics have been developed.

Objectives: To compare the efficacy and safety of infiltrated local anaesthetics with those of topical local anaesthetics for repair of dermal lacerations and to evaluate the efficacy and safety of various single or multi-component topical anaesthetics to identify cocaine-free topically applied local anaesthetics that may provide equivalent analgesia to those containing cocaine.

Search Strategy: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 10); MEDLINE (1966 to November 2010); EMBASE (1980 to November 2010); CINAHL (1982 to November 2010); and reference lists of articles. We also handsearched selected journals, reviewed abstracts presented at international society meetings, reviewed metaregisters of ongoing trials and contacted manufacturers and researchers in the field.

Selection Criteria: We included randomized controlled trials (RCTs) that evaluated the efficacy and safety of topical anaesthetics for repair of torn skin in adult and paediatric patients.

Data Collection And Analysis: Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information. We collected adverse event information from the trials.

Main Results: We included 23 RCTs involving 3128 patients. The small number of trials in each comparison group and the heterogeneity of outcome measures precluded quantitative analysis of data in all but one outcome, pain scores using a visual analogue scale. The majority of trials that compared infiltrated and topical anaesthetics are at high risk of bias, which is likely to affect the interpretation of the results. Several cocaine-free topical anaesthetics were found to provide effective analgesic efficacy. However, the data regarding the efficacy of each topical agent is mostly based upon single comparisons, in trials that have unclear or high risk of bias. Mild, self-limited erythematous skin induration occurred in one case after application of topical tetracaine-adrenaline-cocaine (TAC) where a total of 1042 patients were exposed. No serious complications were reported in any of the patients treated with either cocaine-based or cocaine-free topical anaesthetics.

Authors' Conclusions: Based on mostly descriptive analysis, topical anaesthetics are possibly an efficacious, non-invasive means of providing analgesia prior to suturing of dermal lacerations. However, additional well designed RCTs with low risk of bias are necessary before definitive conclusions can be made.