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Background and Aims The nociception level index (NOL) is a novel nociception monitor, validated for adults, which has recently proved to detect the nociceptive stimuli in paediatrics that still waits for the clinical significance of this opportunity for the nonverbal age (1,2,3). In this case series, we aim to evaluate the effectiveness of the NOL monitor in guiding adequate perioperative analgesia in paediatrics and observe the relation between the NOL and the behavioural pain assessment scales (FLACC, CHIPPS).

Methods After informed parenteral consent, thirteen cases received general anaesthesia to receive fracture surgery under NOL monitorization with a standard pain management protocol of 10 mg/kg (IV) paracetamol and 0,025 mg/kg morphine (IV). Additional morphine bolus doses were applied if only intraoperative NOL were over 25 or decided based on hemodynamics. Postoperative pain was evaluated using FLACC and CHIPPS scores at the PACU, 2nd, 6th, 12th, and 24th hours after surgery. A rescue analgesic was given if the pain score was four or higher.

Results The demographic data present 13 cases (table 1). Intraoperative analgesic doses were only needed when NOL was over 25 (table 2). There was no time when hemodynamic changes indicated pain, and the NOL value was low. Postoperative scores were compatible with low NOL before arousal except for cases 8 and 10, having a high FLACC score with a low CHIPPS at the same time.

Conclusions NOL guidance would be valuable for ensuring intraoperative analgesia for nonverbal pediatric patients. However, additional randomized controlled analyses are needed to validate NOL monitoring in specific age groups.