Pupillary reflex dilation and pain index evaluation during general anesthesia using sufentanil: a double-blind randomized controlled trial.

Aim: In a single-center, double-blind, randomized controlled trial, we evaluated whether pupillometry-controlled use of sufentanil is better than free-choice administration of sufentanil by anesthesiologists. Patients & methods: 61 patients undergoing daycare gynecological or abdominal surgery were enrolled. A pupillometry pain index score chart was introduced for administration guidance of sufentanil. Results: The first objective, patient well-being, did not show a significant difference with painkiller usage and health state index at day 1 postoperatively. Secondly, we experienced difficulty in interpretation of the pupillometry score. Thirdly, opioid usage was higher in the intervention group (20.1 vs 14.8 mcg; p = 0.017). Conclusion: The use of pupillometry and pain index chart for bolus sufentanil with our protocol showed an unwanted higher sufentanil usage without a significant difference in patient wellbeing. (Ethics Committee EC17/28/319 of the University Hospital of Antwerp. Registration at clinicaltrials.gov NCT03248908.).