RESUMEN
OBJECTIVE: To compare the efficacy of the dorsal penile nerve block (DPNB) with a less invasive form of local anesthesia, eutectic mixture of local anesthetic (EMLA) cream, for reduction of pain during neonatal circumcision. DESIGN: Prospective, blinded, randomized, controlled trial. SETTING: Tertiary referral, neonatal intensive care nursery in a university teaching hospital. PATIENTS: Fifty infants >/=341/2 weeks postmenstrual age and stable for discharge at time of circumcision; gestational age at birth 25 to 41 weeks; birth weight 600 to 4390 g; age at study 3 to 105 days. An additional cohort of term newborns (n = 20), who were not randomized, were circumcised without anesthesia. INTERVENTIONS: Administration of either EMLA cream (0.5 g topically 1 hour before circumcision) or 1% lidocaine (0.7-1.0 mL subcutaneously 3 minutes before circumcision). OUTCOME MEASURES: Primary: Neonatal Infant Pain Scale (NIPS) score; secondary: heart rate, respiratory rate. All outcome measures were assessed by an individual who was blinded to the group assignment and did not perform the circumcision. RESULTS: NIPS scores were significantly lower in the DPNB infants (2.3 +/- 1.8) compared with the EMLA infants (4.8 +/- 0.7). NIPS scores in patients circumcised without anesthesia indicated severe pain. There was a significantly greater increase in heart rate over the duration of the circumcision in the EMLA group than in the DPNB group (49 vs 9 beats per minute). Adverse effects included small hematomas at the site of injection in DPNB infants (10/23), mild erythema at 1 and/or 24 hours after circumcision in the EMLA infants (3/21), and penile edema noted 5 days after circumcision requiring removal of the circumcision bell in 1 DPNB infant. CONCLUSIONS: DPNB provides better pain reduction during neonatal circumcision than EMLA cream. EMLA cream may provide pain reduction compared with no anesthesia during neonatal circumcision.