Topical lidocaine-prilocaine versus lidocaine for neonatal circumcision: Arandomized controlled trial

Objective: To evaluate epicutaneous application of 5% lidocaine-prilocaine and 30% lidocaine cream anesthetics for neonatal circumcision. Methods: The efficacy of 5% lidocaine-prilocaine and 30% lidocaine creams w as compared in a randomized, double-blind, placebo-controlled trial. sixty- one neonates were randomly assigned to one of three groups: 5% prilocaine-l idocaine (n = 20), 30% lidocaine (n = 20), and a control group that receive d an acid-mantle cream (n = 21). Heart rate, oxygen saturation, and crying time were monitored before, during, and after circumcision. Blood pressure was measured before and after circumcision. Results: Mean peak heart rates for the 5% lidocaine-prilocaine, 30% lidocai ne, and control groups (+/- standard deviation) were 146 +/- 16, 157 +/- 10 , and 164 +/- 16 beats per minute, respectively. During four of six active phases of circumcision, the 5% lidocaine-prilocaine group suppressed signif icant increases in heart rate better than 30% lidocaine, which was more eff ective than control (dorsal clamp, P < .001; bell clamp on, P = .001; tight ening, P = .001; bell clamp off, P < .001). During tightening of the bell c lamp, significantly less crying was seen in the 5% lidocaine-prilocaine gro up (13 +/- 12 seconds) compared with 30% lidocaine (24 +/- 14 seconds) and controls (38 +/- 27 seconds) (P < .001). The group that received 5% lidocai ne-prilocaine also had no significant increase in systolic (t = 1.6, P = .1 2) or diastolic (t = 1.9, P = .067, respectively) blood pressure, unlike th e group receiving 30% lidocaine (t = 4.8, P = .001 and t = 2.9, P = .009, r espectively) and the placebo group (t = 2.5, P = .023 and t = 2.3, P = .032 ). There were no significant differences in oxygen saturation (alpha = .05, power 0.79). Conclusion: Epicutaneous 5% lidocaine-prilocaine was more effective than 30 % lidocaine for neonatal circumcision, better reducing neonatal stress indi cators. Lidocaine-prilocaine significantly shortened frying time during one of the most painful phases of circumcision. Both topical anesthetics were more effective than placebo in attenuating the behavioral and physiologic i ndicators of neonatal pain. (C) 1999 by College of Obstetricians and Gyneco logists.