The effect of adding dexamethasone to bupivacaine on the duration of postoperative analgesia after caudal anesthesia in children

Abstract

Background Different additives have been reported to prolong the duration of caudal anesthesia in pediatrics. Although these drugs successfully increased the duration of the block, many of them were associated with undesirable adverse effects. Dexamethasone has been found to effectively increase the duration of an epidural block in adults, with no resulting side effects. Objective The aim of this study was to assess the effect of adding dexamethasone to bupivacaine on the duration of a caudal block in pediatric patients. Patients and methods This was a prospective randomized-controlled study that included 80 children, aged 1-6 years, American Society of Anesthesiologists physical status I, undergoing elective unilateral inguinal herniotomy. Patients were randomized to receive 1 ml/kg bupivacaine 0.25% (group B) or a mixture of dexamethasone 0.2 mg/kg added to 1 ml/kg bupivacaine 0.25% (group BD). In the postoperative period, pain was assessed using a modified Objective Pain Scale (mOPS) score until 24 h after surgery and rescue analgesia (oral paracetamol 15 mg/kg) was administered when mOPS score 4 or more was recorded. The primary outcome measure was the time to first analgesic requirement. The number of analgesic doses required in the first 24 h after surgery, residual motor block, sedation scores, intraoperative and postoperative hemodynamic variables, postoperative nausea and vomiting (PONV), and other adverse effects were recorded. Results Group BD showed a significantly longer time to first analgesic requirement than group B. The number of oral paracetamol doses required in the first 24 h was significantly less in group BD. Group BD showed lower mOPS scores than group B. Modified Bromage scale scores, sedation scores, as well as intraoperative and postoperative hemodynamic variables were comparable in the two groups. Group BD showed significantly fewer incidences of PONV compared with group B. Conclusion Adding dexamethasone to bupivacaine prolongs the duration of postoperative analgesia and decreases the incidence of PONV after a caudal block in pediatric patients.