Caudal epidural butorphanol plus bupivacaine versus bupivacaine in pediatric outpatient genitourinary procedures

Study Objective: To investigate the efficacy of adding butorphanol to bupivacaine administered in the caudal epidural space in children undergoing genitourinary (GU) procedures. Design: Randomized, double-blinded, controlled study. Setting: University affiliated pediatric hospital. Patients: 200 ASA physical status I and II male patients between 6 months and 10 years of age. Interventions: Patients were randomized to receive either 0.25% bupivacaine with 1: 200,000 epinephrine alone (Group 1) or 0.25% bupivacaine with 1:200,00 epinephrine plus 30 μg/kg butorphanol (Group 2) administered via the caudal epidural space prior to surgical incision. Measurements and Main Results: Patients were evaluated postoperatively until discharge. Measurements included requirement of additional analgesic, sedation, pain/comfort scores, and a 24-hour analgesic follow-up. Significantly fewer patients in the butorphanol group required rescue morphine sulfate in the postanesthesia care unit (p ≤ 0.001). The total number of morphine doses administered to Group 2 was significantly less than Group 1 (p ≤ 0.001). 52% of patients in Group 1 compared with 28% in Group 2 required administration of additional analgesics following discharge from the hospital (p ≤ 0.003), with 23% of Group 1 requiring a codeine compound compared with 8% in Group 2 (p < 0.03). Conclusions: The addition of 30 μg/kg butorphanol to 0.25% bupivacaine with epinephrine via the caudal epidural space is a safe, effective means to increase duration of analgesia following GU procedures.