REVIEW QUESTION

Can topical anesthetics provide adequate pain control during the repair of skin lacerations?

TYPE OF REVIEW

A systematic review of 25 randomized controlled trials (RCTs).

RELEVANCE FOR NURSING

The repair of superficial skin lacerations is typically a minor procedure performed in an outpatient setting. It can be invasive or noninvasive-using sutures or staples, for example, or adhesives or glue. Pain management is required with either approach, and traditional methods involve infiltration of the wound with local anesthetics, possibly supplemented by systemic analgesics or sedation.

Injecting medication into the skin, however, can cause discomfort and anxiety in patients, especially in children and those with a needle phobia. Therefore, the use of topical agents, such as gels or solutions, to deliver local anesthesia has been proposed as an alternative. These medications need to be managed carefully, however, as high doses can lead to adverse effects such as hypotension, cardiac arrhythmias, double vision, and seizures.

CHARACTERISTICS OF THE EVIDENCE

In total, 25 RCTs, including 3,278 participants, were included in this review. Trials evaluating the analgesic efficacy of topical local anesthetics during skin laceration repair were included, specifically those comparing topical agents with infiltration agents, and those comparing different topical anesthetic formulations. Participants included pediatric and adult patients of any age.

The primary outcome was participant-reported pain intensity during wound repair. Secondary outcomes were indirect indicators of pain intensity during wound repair, such as participants' behavioral responses; and topical anesthetic-related acute toxicity reported shortly after application, such as neurologic and cardiovascular toxicity, and other adverse effects such as an allergic reaction.

All studies reported participants' self-reported pain intensity and 11 of the 25 reported the acute adverse effects of the anesthetic. No serious complications were reported for any participant treated with cocaine-based or cocaine-free topical anesthetics. The small number of trials in each comparison group and the heterogeneity of the outcome measures meant that quantitative data analysis was only performed for one outcome measure: pain intensity. Therefore, analysis was mostly descriptive in nature. Most trials that compared the use of infiltrated and topical anesthetics were at high risk for bias; and each outcome measure was graded as "low" owing to limitations in design and implementation, imprecision of results, and high probability of publication bias.

BEST PRACTICE RECOMMENDATIONS

The authors reported that topical anesthetics may offer an effective and noninvasive method of pain relief for the suturing or stapling of skin lacerations. While no serious adverse effects were reported with the use of cocaine-based topical anesthetics, their continued use was questioned because of the availability, cost-effectiveness, and comparable efficacy of topical anesthetics without cocaine on the market.

RESEARCH RECOMMENDATIONS

Additional well-designed RCTs with low risk of bias are needed to reach definitive conclusions. More investigation is also necessary to compare topical anesthetics with and without cocaine. Future research could also evaluate the recent clinical application of novel formulations of existing local anesthetics such as microsomal encapsulated bupivacaine or those with a long duration of action such as saxotoxin. Many of the trials in this study used observer-reported pain scores or other surrogate measures. Future trials should adopt uniform outcomes that reflect participants' own assessments of procedure-related pain intensity.

REFERENCE