Intraoperative monitoring of nociception has made great progress in adult anesthesia.

However, pediatric data are scarce. The Nociception Level (NOL) is one of the most recent indexes of nociception. Its originality is that it provides a multiparametric assessment of nociception.

In adults, NOL monitoring allowed lower perioperative opioid requirements, hemodynamic stability, and qualitative postoperative analgesia. So far, the NOL has never been used in children.

Our objective was to validate the ability of NOL to provide a quantitative assessment of nociception in anesthetized children.

In 5–12 years old children anesthetized with sevoflurane and alfentanil (10 µg kg−1), before surgical incision, we performed three standardized tetanic stimulations (5 s, 100 Hz) of different intensities (10−30–60 mA) in a randomized order.

NOL, heart rate, blood pressure and Analgesia-Nociception Index variations were assessed after each stimulation.