Nancy Verónica Alva ArroyoJosé Manuel Athié GarcíaEnrique Monares ZepedaDiego Jaime Villalón2026-03-222026-03-22201710.35366/74381https://doi.org/10.35366/74381https://andeanlibrary.org/handle/123456789/66331Precise pain assesment within the Intensive Care Unit (ICU) is essential. It has been noted that approximately 33-35% of nursing staff consistently underestimate their patients' pain. Our study's main objective is to observe if the variations of the pupillary pain index determine a prognostic threshold during tapentadol use, when in the Intensive Care Unit and after discharge. Pupillary measurements were done by local medical personnel by means of the AlgiScan device (videopupillometer) and the visual analogue scale. Adult patients being admitted to the ICU and whose time requirements of opioid infusions were predicted to be longer than 48 hours were considered for inclusion. Designed as a controlled clinical trial, tapentadol use in a group was compared to standard analgesia as a control group. Videopupillometry was performed at four hours post tapentadol administration, then every 12 hours until medical discharge from the ICU. A total of 40 patients were included, 19 in the tapentadol group and 21 in the standard analgesia group. When compared between groups, the numerical variable obtained by pupillometry was found to be different with statistical signifi cance (p < 0.01), with a mean of 11 for the tapentadol group and a mean of 19 in the standard analgesia group. A lower pain score in the tapentadol group when compared with standard analgesia was made evident in this study.esTapentadolMedicineOpioidarticle