Experimental studies in animals have demonstrated tissue injury or noxious stimulation results in long-term functional changes in the central nervous system, with expansion of receptive fields, facilitation of flexor motor neuronal responses and decrease in the threshold of dorsal horn neurons (1–4). Experience from clinical studies following capsaicin stimulation (5,6), thermal injury (7,8), or gynecological laparotomy (9) suggests similar post-injury changes to take place in humans. Consequently, it has been suggested that surgery may lead to spinal cord hyperexcitability, which may amplify and/or prolong postoperative pain (10).
KeywordsPostoperative Pain Opioid Requirement Preemptive Analgesia Secondary Hyperalgesia Neural Blockade
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- 1.Woolf CJ: Central mechanisms of acute pain, Proceedings of the 6th World Congress of Pain. Edited by Bond MR, Charlton JE, Woolf CJ. Amsterdam, Elsevier, 1991, pp. 25–34Google Scholar
- 8.Møiniche S, Dahl JB, Kehlet H: Time course of primary and secondary hyperalgesia after heat injury to the skin. Br J Anaesth 1993 (in press)Google Scholar
- 22.Dahl JB, Daugaard JJ, Rasmussen B, et al: The effect of preemptive epidural analgesia with morphine and bupivacaine on pain at rest and during mobilization following total knee arthroplasty. Acta Anaesthesiol Scand 1993 (in press)Google Scholar
- 29.Lund C: Somatosensory evoked potentials in the assessment of neural blockade. Dan Med Bull 40: 266–272Google Scholar