The effects of a topical anesthetic used prior to newborn circumcision on the parameters of heart rate, respiratory rate, oxygen saturation levels, seconds of crying time, and overt generalized reaction to the procedure were investigated. In the double-blind design, an experimental group (n = 20) received 4% lidocaine cream mixed with 500 mg acid mantle cream two hours before circumcision, and a control group (n = 24) received 500 mg acid mantle cream two hours before circumcision. The circumcision was divided into five events with parameters recorded 30 seconds into each event.

The results showed a significant difference in the heart rate between the treated and untreated group, but the respiratory rate and oxygen saturation levels did not differ significantly. Seconds of crying time also differed significantly between groups, as did overt generalized response. There were no untoward reactions. Results showed that topical lidocaine, simple and safe to use, reduced parameters associated with pain and stress.