[Preemptive effects caused by co-analgesia with ketamine in gynecological laparotomies?]

The preemptive use of analgetics makes it possible to influence sensitization proceedings caused by a trauma. Various mechanisms are effective in central pain treatment. The NMDA receptor plays an important role. The investigation presented was to examine whether an intraoperative combination of analgetics with different points of contact leads to improved postoperative analgesia. Altogether 39 female patients who had to undergo a gynaecological laparotomy were examined. Three groups of 13 patients were randomly formed. In addition to usual general anaesthesia, the patients of group one received 0.5 mg/kg bodyweight ketamine racemate before the skin incision and thereafter 10 micrograms/kg/min ketamine infusion continuously until peritoneum closure and then sodium chloride 0.9% as a placebo after the final skin suture. The patients of group two received placebos before the skin incision and intraoperatively and 0.5 mg/kg bodyweight ketamine after the last skin suture. In group three the patients received placebos at all three points of time. Analgetics consumption, pain intensity, awakening reaction, vital parameters as well as psychomimetic side-effects and nausea/vomiting were listed postoperatively. Between the groups no differences were found regarding postoperative analgetics consumption. In addition, the pain intensity showed no differences regarding an improved postoperative analgesia through the combination of analgetics with different points of contact. The intraoperative combination of ketamine and alfentanil does not lead to a reduction of postoperative pain. No preemptive analgesia is clinically provable.