Intérêt de la pupillométrie pour l'évaluation de la douleur

Various techniques for monitoring the autonomic nervous system balance enable the assessment of pain in wakeful subjects, and of nociception in patients under general anesthesia. Such monitoring techniques primarily allow for a more rational use of analgesics in non-communicative patients (at both ends of life, with neurologic or psychiatric disorders, at post-anesthesia awakening, in intensive care units). In the intraoperative period, these techniques can avoid under- or overdoses of morphine, thus improving the hemodynamic stability of the most vulnerable patients while minimizing the postoperative cases of hyperalgesia. Today, videopupillometry provides a simple way for assessing pain, both in wakeful patients and in patients under general anesthesia. Only dynamic tests such as measuring the pain-induced pupillary dilation reflex or the pupillary light reflex can provide an a posteriori information on the stimulation-induced disbalance, and therefore on the pain/analgesia, or nociception/antinociception balance, at a given instant. Likewise, monitoring the constant fluctuations of the pupillary diameter constitutes a dynamic measure capable of providing information on the pain/analgesia balance on a continuous basis. Videopupillometry thus allows for optimizing pain management in patients with unreliable pain assessment, and for more accurately meeting the analgesic needs of patients under general anesthesia during various surgical phases.