Pain monitoring technology can reduce intraoperative opioid consumption

Reviewed by Emily Henderson, B.Sc.May 26 2021

A new study has shown that effective opioid-sparing anesthesia with dexmedetomidine can be guided with NOL pain monitoring technology (Medasense, Israel). The study showed that the NOL monitor is able to detect the effect of dexmedetomidine on the patient's pain response and enable administration of less intraoperative opioids.

Patients undergoing anaesthesia for surgical procedures are traditionally treated with opioids (e.g., remifentanil) to manage intraoperative pain. But clinicians are progressively seeking to reduce opioid use by introducing multimodal analgesia, a technique that involves a combination of medications that often includes a central alpha agonist, such as dexmedetomidine.

This approach may offer pain relief, offset potentially adverse effects of individual drugs in larger doses and enable a reduction of opioid use during surgery. With this strategy, however, clinicians are not always able to predict whether the impact of the drug combination will be effective or excessive.

The current study addressed this challenge in multimodal analgesia and examined its effectiveness by monitoring pain response (nociception) levels in patients with the NOL monitoring system.

NOL monitoring is a non-invasive multi-sensor AI technology that provides a reliable index to objectively detect and quantify the patient's physiological response to painful stimuli during anaesthesia, when patients can't communicate. This index guides the clinical team in tailored pain medication for each patient. Earlier studies have shown that the NOL index outperforms other indexes for monitoring of pain response to surgical stimuli and that NOL-guided analgesia has resulted in reduced intraoperative opioid consumption as well as less pain after surgery.

Led by Dr. Sean Coeckelenbergh of Erasme University Hospital in Brussels, Belgium, the new randomised controlled study examined 58 patients undergoing NOL-guided analgesia. Patients were randomised to receive either placebo or low-dose dexmedetomidine and both groups received intraoperative antinociception with a target-controlled infusion of remifentanil guided by the NOL index.

The study, just published in the European Journal of Anaesthesiology, has shown that NOL can provide an objective reflection of dexmedetomidine's effects, helping the clinician in the decision-making process when applying multimodal pain relief, with the potential for significant opioid sparing during surgery.

Multimodal anaesthesia has benefits, but it is limited in that we often do not know the exact depth of anaesthesia and antinociception. The NOL index offers us a new way to quantify nociception when combining alpha agonists and opioids."

Dr Sean Coeckelenbergh, Erasme University Hospital