Optimization of Morphinomimetic Administration Intraoperatively: Evaluation of the Impact of the NOL Index on the Occurrence of Postoperative Adverse Events Related to Morphinomimetics

Reducing the quantity of morphinomimetics during the operative period reduces the prevalence and intensity of adverse effects. However, morphinomimetics are indispensable during surgery, as they limit the autonomic nervous system's deleterious reactions to nociception. The administration of these drugs in intravenous boluses during surgery is usually guided by their duration of action and by variations in heart rate and blood pressure. Other events, such as hypovolemia or extreme surgical position, may stimulate the autonomic nervous system outside of nociception. These events, along with routine drug administration, can lead to undue consumption of morphinomimetics. The Nol index, a multiparametric monitor of nociception, is based on analysis of variations in plethysmography waveform, heart rate and skin conductance. It has been demonstrated that the use of this type of monitor can reduce intraoperative consumption of morphinomimetics and optimize their administration. Does intraoperative morphinomimetic administration optimized by the NOL index have an impact on the occurrence of dose-dependent adverse effects?