Update on preemptive analgesia

Abstract

Perioperative pain remains prevalent and poorly treated. Apart from its impact on the rate and unpleasantness of recovery from surgery, pain often remains as a residual aftereffect of surgery even though tissue healing appears complete. A growing appreciation for the underlying neurobiology of pain has identified mechanisms that can enhance the intensity of perioperative pain and even lead to more prolonged painful conditions. An essential observation is that tissue injury and the resulting nociceptor barrage initiates a cascade of events that can indelibly alter pain perception. Preemptive analgesia is the concept of initiating analgesic therapy before the onset of the noxious stimulus so as to prevent the nociceptor barrage and its consequences. However, preemptive analgesia, though firmly grounded in the neurobiology of pain, has yet to realize its anticipated clinical potential. As data accumulates, it has become clear that clinical studies emulating those from the laboratory and designed around a relatively narrow definition of preemptive analgesia have been largely unsupportive of its use. Nevertheless, preemptive analgesic interventions that recognize the intensity, duration, and somatotopic extent of major surgery can help reduce perioperative pain and its longer-term sequelae.