Rockemann M G, Seeling W, Bischof C, Börstinghaus D, Steffen P, Georgieff M
Department of Anesthesiology, University of Ulm, Germany.
Anesthesiology. 1996 May;84(5):1027-34. doi: 10.1097/00000542-199605000-00003.
Surgical trauma induces nociceptive sensitization leading to amplification and prolongation of postoperative pain. While preemptive analgesic treatment with numerous agents has been successful in experimental animals, results of human studies remain conflicting. The authors used a multimodal approach for preemptive analgesia before abdominal surgery: diclofenac and metamizole inhibit prostaglandin synthesis, thus influencing peripheral sensitization; epidural local anesthetics induce conduction block, epidural opioids inhibit nociceptive synaptic transmission, and metamizole induces descending inhibition. The interaction of these drugs might suppress spinal nociceptive sensitization and postoperative analgesic demand.
One hundred forty-two patients scheduled for major abdominal surgery were randomly assigned to one of three groups and studied prospectively. Epidural catheters in groups 1 and 2 were placed at interspaces T8-T10, the position of the catheter was confirmed by epidurography, and sensory testing after administration of 5 ml mepivacaine 1%. Group 1 received 75 mg intramuscular diclofenac, 1000 mg intravenous metamizole, 5.3 +/- 1 mg epidural morphine, and 15-20 ml mepivacaine 1% 85 +/- 41 min before skin incision. Epidural analgesia was maintained by injections of 0.1 ml.kg-1.h-1 mepivacaine 1%. Group 2 patients received the balanced analgesia regimen before wound closure (221 +/- 86 min after skin incision). Group 3 patients did not receive any study substances. General anesthesia was induced with 5 mg/kg thiopental and 2 micrograms/kg fentanyl and maintained with enflurane and nitrous oxide. Postoperative analgesia consisted of patient-controlled intravenous morphine over 5 days.
Median visual analog scale pain intensities were < 3 cm and did not differ among the groups. Morphine consumption per hour on postoperative day 2 was 0.8 +/- 0.1 mg/h (group 1) < 1.2 +/- 0.1 mg/h (group 2) = 1.1 +/- 0.1 mg/h (group 3) and cumulative morphine consumption (in mg) on the morning of day 5 was 95 +/- 9 (group 1) < 111 +/- 11 (group 2) < 137 +/- 10 (group 3).
A significant reduction of patient controlled analgesia requirements could be achieved by our preincisional balanced analgesia regimen compared to application before wound closure. The more distinct difference between patients receiving balanced analgesia and those in the control group is based on the analgesic action of the study substances, which lasted about 14 h.
手术创伤会引发伤害性感受敏化，导致术后疼痛加剧和持续时间延长。尽管使用多种药物进行超前镇痛治疗在实验动物中取得了成功，但人体研究结果仍存在矛盾。作者采用多模式方法对腹部手术患者进行超前镇痛：双氯芬酸和安乃近抑制前列腺素合成，从而影响外周敏化；硬膜外局部麻醉药诱导传导阻滞，硬膜外阿片类药物抑制伤害性突触传递，安乃近诱导下行抑制。这些药物的相互作用可能会抑制脊髓伤害性感受敏化和术后镇痛需求。
142例计划进行腹部大手术的患者被随机分为三组，进行前瞻性研究。第1组和第2组的硬膜外导管置于T8 - T10间隙，通过硬膜外造影确认导管位置，并在给予1%甲哌卡因5 ml后进行感觉测试。第1组在皮肤切开前85±41分钟接受75 mg肌肉注射双氯芬酸、1000 mg静脉注射安乃近、5.3±1 mg硬膜外吗啡和15 - 20 ml 1%甲哌卡因。通过每小时注射0.1 ml·kg⁻¹·h⁻¹的1%甲哌卡因维持硬膜外镇痛。第2组患者在伤口缝合前（皮肤切开后221±86分钟）接受平衡镇痛方案。第3组患者未接受任何研究药物。采用5 mg/kg硫喷妥钠和2 μg/kg芬太尼诱导全身麻醉，并用恩氟烷和氧化亚氮维持。术后镇痛为患者自控静脉注射吗啡，持续5天。
视觉模拟评分法疼痛强度中位数<3 cm，三组之间无差异。术后第2天每小时吗啡消耗量为0.8±0.1 mg/h（第1组）<1.2±0.1 mg/h（第2组） = 1.1±0.1 mg/h（第3组），第5天上午吗啡累积消耗量（mg）为95±9（第1组）<111±11（第2组）<137±10（第3组）。
与伤口缝合前应用相比，我们的切开前平衡镇痛方案可显著降低患者自控镇痛的需求。接受平衡镇痛的患者与对照组患者之间更明显的差异基于研究药物的镇痛作用，该作用持续约14小时。
