Recent Topics in the Management of Pain: Development of the Concept of Preemptive Analgesia

Abstract

Recent studies concerned with the relationship between injury responses and acute and chronic pain were reviewed. Basic and clinical studies of pain have revealed that a large proportion of the mechanisms that produce strange signs and symptoms, such as allodynia, hyperalgesia and hyperpathia, after tissue injury are ascribed to increased excitability, or to sensitization derived from biological changes in spinal dorsal horn cells subjected to excessive noxious stimuli from injured tissues. Preemptive analgesia has been under consideration as a means of preventing the predictable sensitization to pain that follows surgery. The findings of many clinical investigations, however, remain controversial. This report discusses the importance of preemptive analgesia including the possibilities of prevention, and of extension to the control, of chronic pain syndromes.