Comparison of analgesic effects of epidural morphine and epidural non-morphine drugs

本研究旨在开发临床有效的硬膜外非吗啡用于术后镇痛，结果及结论如下：1)硬膜外吗啡对大鼠躯体痛和内脏痛均有效。相反，硬膜外给予美托咪定（一种镇静剂）、咪达唑仑（一种镇静剂）、氯胺酮（一种麻醉剂）和非吗啡类阿片类药物（丁托啡诺和丁丙诺啡）仅能引起轻度至中度镇痛。除吗啡外，这些药物的联合使用对镇痛也不是很有效。2)硬膜外给予大剂量局麻药（利多卡因、布比卡因）可诱导强效镇痛，但镇痛持续时间短，且引起盆腔肢体严重共济失调。低剂量布比巴伐卡因与丁托啡诺或丁丙诺啡联用可诱导对躯体或内脏疼痛的有效镇痛，且无明显的共济失调。这些组合，特别是布比卡因和丁丙诺啡的组合在硬膜外使用时可以替代吗啡。3)硬膜外吗啡或布比卡因丁丙诺啡对各种手术患者术后疼痛的治疗效果较好。尽管需要比上述结果估计的剂量更高的布比卡因剂量，但在犬病例中，硬膜外布比卡因和丁丙诺啡引起轻度共济失调。综上所述，硬膜外布比卡因和丁丙诺啡用于犬术后镇痛是有效的。

This study was designed to develop the clinically effective epidural non-morphine for post-operative analgesia and the followings are the results and conclusion.1) Epidural morphine was effective for both somatic and visceral pain in rat model. In contrast, epidural administration of medetomidine (a sedative), midazolam (a tranquilizer), ketamine (an anesthetic), and non-morphine opioids(butorphanol and buprenorphine)induced only mild to moderate analgesia. The combinations of these drugs except for morphine were not also very effective for analgesia.2) Epidural administration of high dose of local anesthetics(lidocaine and bupivacaine)induced potent analgesia, however the duration of analgesia was short and caused severe ataxia of pelvic limbs. The combinations of low dose of bupibavacaine and butorphanol or buprenorphine induced potent analgesia against either somatic or visceral pain without apparent ataxia. These combinations, especially the combination of bupivacaine and buprenorphine may be a substitute of morphine when used epidurally.3) Epidural morphine or bupivacaine and buprenorphine were effective for post-operative pain management in clinical cases that were underwent various surgery. Although the higher dose of bupivacaine than the dose which was estimated from the results obtained above was needed, epidural bupivacaine and buprenorphine caused mild ataxia in dog cases. In conclusion, epidural bupivacaine and buprenorphine is effective for post-operative analgesia in dogs.