Methods for the assessment of opioid-induced hyperalgesia in the perioperative period

BACKGROUND AND OBJECTIVES:Opioid-induced hyperalgesia is a topic not yet fully understood in terms of mechanisms, diagnosis, prevention and treatment. Thus, it seems of great importance to evaluate this phenomenon that negatively affects the treatment of pain. The purpose of this study was to describe what tools to use to evaluate perioperative hyperalgesia.CONTENTS:Several methods have been suggested to evaluate opioid-induced hyperalgesia, such as measure of pain intensity, opioid consumption, and evaluation of secondary hyperalgesia with algometer and Von Frey monofilaments. The measurement of some substances, such as cytokines, glutamate, and dynorphin has also been used.CONCLUSION:There are several ways to evaluate opioidinduced hiperalgesia, easily reproducible tests should be chosen and which have also been described in previous studies.