Rectus sheath block versus local anesthetic infiltration in pediatric laparoscopic inguinal hernia repair: a randomized controlled trial

Rectus sheath block (RSB) and local anesthetic infiltration (LAI) are used for postoperative analgesia in pediatric laparoscopic inguinal hernia repair. However, whether the analgesic effect of RSB is superior to LAI remains unclear. The authors hypothesized that RSB would reduce opioid consumption in patients. METHODS: Patients aged 3–14 years scheduled for laparoscopic inguinal hernia repair were randomly allocated to the RSB, local anesthetic infiltration high concentration (LAIHC), local anesthetic infiltration low concentration (LAILC), or control groups. Preoperatively, they received 0.4 ml/kg of 0.25% ropivacaine (RSB), 0.4 ml/kg of 0.25% ropivacaine (LAILC), or 0.2 ml/kg of 0.5% ropivacaine(LAIHC), and 0.2 ml/kg of normal saline (control). The primary outcome was equivalent morphine consumption. RESULTS: The authors analyzed 136 patients (RSB, 33; LAIHC, 34; LAILC, 35; control, 34). Intraoperative morphine equivalent consumption was lower in the RSB group [0.115 (0.107−0.123)] than in the LAIHC [0.144 (0.137−0.151)], LAILC [0.141 (0.134−0.149)], and control [0.160 (0.151−0.170)] groups (P<0.001). In the post-anesthesia care unit, morphine equivalent consumption differed between the RSB [0.018 (0.010–0.027)], LAIHC [0.038 (0.028–0.049)], LAILC [0.056 (0.044–0.067)], and control [0.074 (0.063−0.084)] groups (P<0.001). The rescue morphine equivalent consumption did not differ significantly between the RSB [0.015 (0.007–0.023)] and LAIHC [0.019 (0.010–0.029)] groups, which were lower than that in the control group [0.037 (0.029–0.045)] (P=0.001). CONCLUSIONS: RSB can provide effective analgesia for pediatric laparoscopic inguinal hernia repair, with better effectiveness than that of LAI at the same dose.