Many newborn males continue to undergo neonatal circumcision without anesthesia in spite of evidence that the procedure causes pain and distress. Several anesthetic techniques have been described for neonatal circumcision, but ring block of the penis has mainly been used in older children and adults. Hardwick-Smith and colleagues studied the effectiveness of penile ring block in reducing the indicators of distress during and after neonatal circumcision.

Forty healthy infants scheduled for circumcision were included in the study and were randomly assigned to receive either a penile ring block or no anesthesia after obtaining informed parental consent. The ring blocks were each performed by the same researcher using a standard technique. After a three-minute waiting period, circumcision using a Gomco clamp was also performed by the same operator on all infants. Indices of perceived pain including behavior, heart rate, respiratory rate and oxygen saturation percentage were recorded at baseline, at 10 intervals during the procedure and at two hours after circumcision. Behavior was assessed using a standardized six-point scale of degree of arousal. Crying time was documented by tape recordings, and other indices were monitored.

The two groups of infants were comparable in demographic, behavioral and other characteristics before the procedure. Infants receiving the block had a mean reduction of approximately two minutes in crying time (36 percent, compared with control subjects) and a significantly decreased arousal state. Anesthetized infants had returned to basal levels of arousal within two minutes of the procedure, but the control infants remained significantly aroused. Non-anesthetized infants showed significantly increased heart and respiratory rates during the procedure. A trend toward greater oxygen desaturation was documented in these infants. Both groups had returned to baseline levels within two hours of the circumcision.

The authors conclude that ring block provides safe and effective short-term anesthesia for neonatal circumcision. The fascia is not pierced, so there is less potential for hematoma formation and other bleeding than with the dorsal penile nerve block. The technique was easy for the clinician to learn and perform, and no complications were encountered in this study.