Reduced postoperative pain in patients receiving nociception monitor guided analgesia during elective major abdominal surgery: a randomized, controlled trial

• Published in: Journal of clinical monitoring and computing Vol. 37; no. 2; pp. 481 - 491
• Main Authors: Fuica, Rivka, Krochek, Carlos, Weissbrod, Rachel, Greenman, Dimitri, Freundlich, Andres, Gozal, Yaacov
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.04.2023; Springer Nature B.V
• Subjects: Abdomen; Abdominal surgery; Adult; Analgesia; Analgesics, Opioid; Anesthesia; Anesthesiology; Artificial Intelligence; Consumption; Critical Care Medicine; Fentanyl; Fentanyl - therapeutic use; Health Sciences; Hemodynamics; Humans; Informed consent; Intensive; Medicine; Medicine & Public Health; Morphine; Nociception; Original Research; Pain; Pain, Postoperative - drug therapy; Postoperative period; Prospective Studies; Sevoflurane; Statistics for Life Sciences; Surgery; Nociception; Opioid; Postoperative pain; Nociception level-guided analgesia; Artificial Intelligence; Personalized Anesthesia
• ISSN: 1387-1307; 1573-2614
• DOI: 10.1007/s10877-022-00906-1

The Nociception Level index (NOL™) is a multiparameter index, based on artificial intelligence for the monitoring of nociception during anesthesia. We studied the influence of NOL-guided analgesia on postoperative pain scores in patients undergoing major abdominal surgery during sevoflurane/fentanyl anesthesia. This study was designed as a single-center, prospective randomized, controlled study. After Institutional Review Board approval and written informed consent, 75 ASA 1–3 adult patients undergoing major abdominal surgery, were randomized to NOL-guided fentanyl dosing (NOL) or standard care (SOC) and completed the study. The sevoflurane target MAC range was 0.8–1.2. In the NOL-guided group (N = 36), when NOL values were > 25 for at least 1 min, a weight adjusted fentanyl bolus was administered. In the control group (N = 39) fentanyl administration was based on hemodynamic indices and clinician judgement. After surgery, pain, was evaluated using the Numerical Rating Scale (NRS) pain scale, ranging from 0 to 10, at 15 min intervals for 180 min or until patient discharge from the PACU. Median postoperative pain scores reported were 3.0 [interquartile range 0.0–5.0] and 5.0 [3.0–6.0] at 90 min in NOL-guided and control groups respectively (Bootstrap corrected actual difference 1.5, 95% confidence interval 0.4–2.6). There was no difference in postoperative morphine consumption or intraoperative fentanyl consumption. Postoperative pain scores were significantly improved in nociception level index-guided patients. We attribute this to more objective fentanyl dosing when timed to actual nociceptive stimuli during anesthesia, contributing to lower levels of sympathetic activation and surgical stress. Clinicaltrials.gov identifier: NCT03970291 date of registration May 31, 2019.