Newborn/infant parasympathetic evaluation (NIPE) to evaluate intraoperative pain response in infants undergoing laparoscopic inguinal hernia repair under general anaesthesia + caudal block vs general anaesthesia + local infiltration.

Background: We have demonstrated that the Newborn Infant Parasympathetic Evaluation (NIPE), based on heart rate variability (HRV) is able to objectively detect intraoperative and post-operative painful stimuli. Our data suggest that laparoscopic inguinal hernia repair is more painful that open inguinal hernia repair both in the intraoperative and postoperative period. In addition, in a small observational study, we found that the intra-operative skin incision and creation of pneumoperitoneum are not adequately covered by the caudal block during laparoscopic inguinal hernia repair. In this prospective randomised controlled trial, we will compare infants undergoing laparoscopic inguinal hernia repair under general anaesthesia + caudal block vs general anaesthesia + local anaesthetic infiltration to establish which of these two pain management strategies provides better pain control in the intraoperative and postoperative period. Methods: Children younger than 2 years will be enrolled over a 12-month period in this randomised controlled study. Patients scheduled for elective laparoscopic inguinal hernia repair will be included. Children with a history of premature delivery or neurological, cardiac or respiratory conditions will be excluded. Infants will be randomly allocated to receive either caudal block or local anaesthetic infiltration during laparoscopic inguinal hernia repair under general anaesthesia. Non-invasive mean blood pressure (MBP), heart rate (HR) and NIPE values will be recorded just before and after general anaesthesia with endotracheal intubation, during surgery and in recovery. NIPE values will be correlated with post-operative analgesia requirement.