Study objective: To compare the anesthetic efficacy of EMLA (eutectic mixture of local anesthetics) cream with that of TAC (tetracaine, adrenaline, and cocaine) solution for suturing uncomplicated extremity wounds.
Methods: We conducted a prospective, single-blind, randomized trial in a convenience sample of 32 children, ages 5 to 18 years, who required repair of an extremity laceration. Eligible wounds were less than 5 cm long and less than 12 hours old. Lacerations involving digits, deep tissues, or musculature were excluded. Patients receiving medications that predisposed them to methemoglobinemia were also excluded. Lacerations were treated with TAC .1 mL/kg (maximum, 3.0 mL) or EMLA .15 g/kg (maximum, 5.0 g). Anesthesia was assessed every 10 minutes. TAC and EMLA were allowed to remain on the wounds for a maximum of 30 and 60 minutes, respectively. Anesthesia was deemed successful if no supplemental lidocaine was required, as judged by a suturing caregiver who was blinded to the anesthetic used.
Results: The two groups were similar with regard to age, sex, wound length and depth, and wound age. EMLA-treated wounds were repaired without supplemental anesthesia more often than TAC-treated wounds: 13 of 16 (85%) versus 7 of 16 (45%, P= .03). More time was required for EMLA to cause anesthesia (55 versus 29 minutes, P<.01). Dehiscence occurred in one wound in each group; no wound infections were observed.
Conclusion: EMLA appears to be superior to TAC for anesthesia of simple extremity lacerations in that those wounds treated with EMLA required supplemental anesthesia less often. EMLA required approximately 1 hour to cause optimal anesthesia in open wounds. Protocols should be developed to allow efficient use of EMLA for anesthesia of extremity lacerations in the ED.