Impact of Intraoperative Non-invasive Analgesia Monitoring Using Nociception Level Index on Patient Management

This prospective randomised clinical trial aims to assess the impact of intraoperative nociception monitoring using NOL on anesthetic management during major abdominal surgery. Additionally, the study will objectively evaluate using NOL how intravenous lidocaine administration, influences opioid requirements and the effect of this multimodal approach on early postoperative outcomes. The investigators hypothesize that NOL-guided intraoperative opioid administration reduces both intraoperative and postoperative opioid use, positively influencing 24-hour outcomes. Furthermore, the addition of intraoperative lidocaine in NOL-guided analgesia may further decrease opioid consumption.