A randomized trial to evaluate the effect of two topical anesthetics on pain response during frenotomy in young infants

Objective. To examine the comparative effectiveness of two topical anesthetics in controlling the pain associated with tongue-tie release (frenotomy) in young infants. Design. Randomized trial. Setting. A Pediatric Craniofacial Clinic. Subjects. Forty-two infants who were referred for frenotomy were randomly allocated to receive the topical anesthetic gel 2% tetracaine or 20% benzocaine applied prior to frenotomy. Frenotomies were videotaped. The primary outcome measure was the Neonatal Facial Coding System (NFCS) score. Secondary outcome measures included cry duration and a visual analog scale (VAS) assessed by the parents. Results. The two groups were comparable with regard to weight, age, gender, previous painful experience, and last feeding time. Median NFCS scores prior to frenotomy in the tetracaine and the benzocaine groups were 4.5 (IQR: 0.75-10.2) and 3.5 (IQR: 0-9.5), respectively (P=0.89, 95% CI -3 to 4). During frenotomy, median NFCS score increased to 28 (IQR: 24.5-30.25) in the tetracaine group (P < 0.0001, median difference -22, 95% CI -24.5 to -19), and to 28 (IQR: 26-30) in the benzocaine group (P < 0.0001, median difference -23, 95% CI -27 to -17). Mean cry durations in the tetracaine and the benzocaine groups were 69.4 seconds and 63.9 seconds, respectively (P=0.32, 95% CI -47 to 15), and mean VAS scores were 57.2 and 58.2, respectively (P=0.89, 95% CI -15.2 to 13.4). Conclusions. These topical anesthetics seem ineffective in controlling the pain associated with frenotomy. Clinicians should continue to search for an effective treatment for this procedure.