Three concentrations of levobupivacaine for ilioinguinal/iliohypogastric nerve block in ambulatory pediatric surgery

Study Objective: To compare the postoperative analgesia of three different concentrations of levobupivacaine for ilioinguinal/iliohypogastric (II/IH) block in children undergoing inguinal hernia repair. Design: Double-blind, prospective, randomized, controlled trial. Setting: Operating room and postoperative recovery area of a university hospital. Patients: 73 ASA physical status I and II children, aged one to 6 years, scheduled for outpatient inguinal hernia repair. Interventions: Patients were randomized to receive one of three levobupivacaine concentrations: 0.125% (L0.125), 0.25% (L0.25), or 0.375% (L0.375). All patients received standard anesthesia with sevoflurane and II/IH nerve block. Measurements: Heart rate (HR), non invasive blood pressure (NIBP), respiratory rate, end-tidal carbon dioxide concentration (ETCO₂), and oxygen saturation via pulse oximetry (SpO₂) were monitored during surgery. Postoperative pain scores with CHEOPS (Children's Hospital of Eastern Ontario Pain Scale) and need for rescue analgesia postoperatively were measured and recorded. Main Results: 60 patients entered the postoperative observational period. The number of patients who received rescue analgesia was comparable in the three groups. In Group L0.125, mean CHEOPS score was significantly higher, and time to first administration of rescue analgesia was shorter, than in the other two groups (P <0.05). Pain scores and time to first administration of rescue analgesia were comparable between Groups L0.25 and L0.375. Conclusions: II/IH nerve block using 0.4 mL kg^-1 of 0.25% levobupivacaine provided satisfactory postoperative pain relief after inguinal herniorraphy.