De la « Preemptive Analgesia » à l'analgésie préventive

The goal of preemptive analgesia is to prevent nociceptive inputs from damaged tissues to reach and to sensitize the central nervous system, thereby to reduce the expression of postinjury pain. Although extremely attractive, the concept of preemptive analgesia has only brought deceiving results in the perioperative setting. Recent experimental models of incisional pain clearly show that any analgesic treatment administered before incision is not superior to the same treatment provided after incision because, when the effects of the analgesic treatment abate, the wound is able to reinitiate the central sensitization. Consequently, preemptive analgesia has evolved to the concept of preventive analgesia, a broader definition, which involves any perioperative analgesic and antihyperalgesic treatments aimed to control central nervous system sensitization and to reduce the development of persistent post-surgical pain. In preventive analgesia, both the duration and the efficacy of the treatment are more important than the timing of administration of the drugs. Recent clinical studies have highlighted the fact that an optimal control of preoperative, peroperative and postoperative pain is mandatory to ensure the success of preventive analgesia. Furthermore, progresses made in the assessment of endogenous mechanisms of pain processing should allow to improve even more preventive analgesia by an individualization of analgesic and antihyperalgesic perioperative treatments.