The majority of postoperative patients report moderate to severe pain, possibly related to opioid underdosing or overdosing during surgery.

Objective guidance of opioid dosing using the Nociception Level (NOL) index, a multiparameter artificial intelligence-driven index designed to monitor nociception during surgery, may lead to a more appropriate analgesic regimen, with effects beyond surgery.

We tested whether NOL-guided opioid dosing during general anaesthesia results in less postoperative pain.

In this two-centre RCT, 50 patients undergoing abdominal surgery under fentanyl/sevoflurane anaesthesia were randomised to NOL-guided fentanyl dosing or standard care in which fentanyl dosing was based on haemodynamics. The primary endpoint of the study was postoperative pain assessed in the PACU.

Results

Median postoperative pain scores were 3.2 (inter-quartile range 1.3–4.3) and