[Pre-emptive analgesia-prophylaxis of postoperative pain.]

Pain prophylaxis is an everyday experience in clinical anaesthesia. There is now considerable experimental evidence that short-term nociceptive stimuli evoke a long-lasting excitatory state of the central nervous system. This excitatory state can be largely prevented by relatively small doses of anaesthetics (local anaesthetics, opioids) given prelesionally. Suchpre-emptive analgesia is the theoretical basis of the clinical experience cited above. This experimental knowledge has clinical applications in the field of postoperative analgesia-which, as is well known, is the Cinderella of anaesthesia. Al-thoughs sound knowledge of the methods is available, postoperative pain relief is very often inadequate. because of organizational difficulties. Pre-emptive analgesia reduces the frequency and intensity of postoperative pain. Infiltration of the surgical incision with local anaesthetics, regional blockades, and spinal and epidural analgesia, all performed preoperatively, and also the administration of analgesies with the premedication, produce postoperative analgesia lasting longer than the known duration of any of these alone. The efficiency of these methods has been scientifically proved during recent years. Pre-emptive analgesia is advantageous in out-patient surgery as well as for routine clinical anaesthesia, and has proved effective in the prevention of phantom limb pain. Many questions on the nature and clinial application of pre-emptive analgesia are still unanswered. However, its ease of performance and the clear clinical advantages of pain prophylaxis mean that it should have a place in the everyday practice of anaesthesia.