LAT (lidocaine-adrenaline-tetracaine) versus TAC (tetracaine-adrenaline-cocaine) for topical anesthesia in face and scalp lacerations

The study objective was to compare the topical anesthetic LAT (4% lidocaine, 1:2,000 adrenaline, 1% tetracaine) to TAC (0.5% tetracaine, 1:2,000 adrenaline, 11.8% cocaine) for efficacy, adverse effects, and costs. The study design was a randomized, prospective, double blind clinical trial set in an inner-city emergency department with an emergency medicine residency program. Adults with linear lacerations of the face or scalp were eligible for inclusion in the study. Patients had lacerations anesthetized with topical TAC or LAT according to a random numbers table. A total of 95 patients were included in the study with 47 receiving TAC and 48 receiving LAT. Patients stated the number of sutures causing pain and patients and physicians rated the overall pain of suturing using a standard visual analog scale (VAS). The power of the study to determine a ranked sum difference of 15 was 0.8. Visual analog scale results and number and percentage of sutures causing pain were compared using Wilcoxonʹs Rank Sum Test. According to patients, the percentage of sutures causing pain was significantly fewer for LAT than TAC (P = .036, Interquartile Range 0.13 to 0.0 for LAT, 0.25 to 0 for TAC). Physicians found LAT statistically more effective than TAC (P = .0093, Interquartile Range 1 to 0 for LAT, 2 to 0 for TAC) but patients did not report a difference (P = .266, Interquartile Range 1 to 0 for both LAT and TAC). Our cost per application was $3.00 for LAT compared to $35.00 for TAC. Follow-up was accomplished in 91 of 95 patients (95%) with no reported complications for either medication. In conclusion, LAT worked at least as effectively as TAC for topical anesthesia in facial and scalp lacerations. Considering the advantages of a noncontrolled substance and less expense, LAT seems to be better suited than TAC for topical anesthesia in laceration repair.