Effects of ropivacaine infiltration on cortisol and prolactin responses to postoperative pain after inguinal hernioraphy in children

Background/Purpose: Painful interventions may have a serious adverse psychological impact, particularly in young patients. Inguinal hernia repair is the most common surgical outpatient procedure performed on infants and children. The aim of this study was to compare the effects of pre- and postincisional infiltration of the surgical area with ropivacaine on cortisol (C) and prolactin (PRL) release and postoperative pain in children undergoing inguinal hernia repair. Methods: Forty-five school-age children, aged 6 to 10 years, undergoing outpatient inguinal hernia repair under general anesthesia were placed randomly into 3 groups. Preincisional wound infiltration of 3 mg/kg ropivacaine was performed in group I patients before surgery. Postincisional wound infiltration was performed in group II patients after hernia repair but before skin closure, and group III patients (controls) did not received any local anesthetic. In the postanesthesia care unit (PACU), objective pain assessments were performed every 5 minutes using a standardized 10-point objective pain scale. Results: Plasma C concentrations increased at the end of the operation in all groups but significantly only in the control group (P < .001). There was no significant difference between the pre- and postincisional groups with regard to pre- and postoperative C alterations (P > .05). Although plasma PRL concentrations increased significantly at the end of the operation in the control group (P < .001), no significant difference was found between pre- and postoperative values in the infiltration groups (P > .05). The pre- and postoperative plasma PRL differences were significant between only groups I and III (P < .001). Conclusions: The findings of the current study suggest that wound infiltration with ropivacaine decreases the stress response to surgery and the postoperative pain. (C) 2004 Elsevier Inc. All rights reserved.