Single level paravertebral versus caudal block in paediatric inguinal surgery

Paravertebral block (PVB) has been used for postoperative analgesia in children since 1992. There are no prospective randomised studies comparing the use of PVB versus caudal block (CB) for outpatient inguinal hernia repair surgery. The hypothesis of this study is that a single level, single injection PVB can provide a longer duration of analgesia and less requirement for supplemental analgesia than single shot CB for children undergoing inguinal surgery. Seventy children, aged three to seven, American Society of Anesthesiologists score I to II, having unilateral inguinal surgery were enrolled in the study. The patients were divided into two randomised groups. In group PVB, a single shot of 0.2 ml/kg levobupivacaine was administered via the lumbar paravertebral route and in group CB, patients were given 1 ml/kg levobupivacaine caudally. Sevoflurane concentration was evaluated after induction and recorded during incision, sac traction and closure. Face, legs, activity, cry and consolability (FLACC) scores, heart rate, blood pressure and SpO2 were evaluated postoperatively. Only four (11.4%) patients in the PVB group needed rescue analgesic drugs compared to 12 (34.3%) patients in the CB group (P = 0.044). Patients were given tramadol as rescue analgesia in the first four postoperative hours. No other supplemental analgesic drug was given apart from tramadol. FLACC scores were the same in the both groups. Parental satisfaction was significantly higher in the PVB group compared to the CB group (74.3 vs 40%, P = 0.01). This study has demonstrated that a single level single injection paravertebral block provides superior intraoperative and postoperative analgesia when compared to a caudal block for unilateral inguinal hernia repair.