Thirty newborns were studied in a randomized, double-blind, placebo-controlled study; 15 received a topical 30% lidocaine cream and 15 received the cream base alone. Vital signs were recorded, and preoperative and postoperative serum beta-endorphin and lidocaine concentrations were measured. A videotape of the newborn was used to score behavioral changes.Results
Comparisions of the vital signs precircumcision and postcircumcision showed no differences between the placebo and treatment groups, with the exception of mean systolic blood pressure, which significantly increased in the placebo-treated newborns (P < .05). Serum beta-endorphin concentrations increased postoperatively in 11 of 15 subjects receiving placebo, but decreased or remained unchanged in 10 of 15 subjects receiving lidocaine (P = .03, Fisher's exact test). When stress-related behaviors in the precircumcision and postcircumcision periods were compared, the mean increase in their occurrence was greater in the placebo than in the treatment group. There was no significant absorption of lidocaine as measured in the serum.Conclusion
Topical application of a 30% lidocaine cream as used in this study may be a safe and efficacious anesthetic for circumcision. Pediatrics 1993;92:710-714; neonate, circumcision, lidocaine, anesthetic, beta-endorphin.