Stewart David J, Lambert Edward W, Stack Kimberly M, Pellegrini Joseph, Unger Daniel V, Hood Raymond J
Department of Anesthesia, Naval Medical Center, 620 John Paul Jones Circle, Portsmouth, VA 23708, USA.
J Bone Joint Surg Am. 2005 Jan;87(1):140-4. doi: 10.2106/JBJS.D.01912.
Intra-articular narcotics have proven efficacy for providing pain relief following knee arthroscopy. This effect is short-lived. Methadone, with its long serum half-life (thirty-five hours, compared with two hours for morphine) could provide improved and prolonged pain relief. The purpose of the present study was to examine the effects of an intra-articular injection of methadone on postoperative analgesia following arthroscopic anterior cruciate ligament reconstruction.
Sixty-five skeletally mature patients undergoing primary anterior cruciate ligament reconstruction were randomly assigned to one of three groups, all of which received an intra-articular injection consisting of 9.5 mL of 0.5% bupivacaine with 1:200,000 epinephrine at the completion of the procedure. In addition, the remaining 0.5 mL of the syringe was filled with one of three substances. The study group (twenty-five patients) received 5 mg of methadone, the comparison group (twenty-one patients) received 5 mg of morphine, and the control group (nineteen patients) received 0.5 mL of saline solution. All supplemental pain medications were given on an as-needed basis, recorded, and converted to morphine equivalents. Specific variables that were measured included supplemental analgesia requirements during both the inpatient period and the outpatient period (from the time of discharge to the seventh postoperative day) and pain scores.
There was no significant difference in inpatient (p = 0.998) or outpatient (p = 0.887) supplemental analgesic requirements or pain scores between the methadone group (Group 1) and the control group (Group 3). The morphine group (Group 2) required significantly less inpatient (p = 0.014) and outpatient (p = 0.044) supplemental analgesia compared with the control group (Group 3). There were no complications.
The present report represents the first known study of the use of intra-articular methadone and establishes that this analgesic is safe at a single dose of 5 mg. At this dose, however, methadone does not provide improved postoperative analgesia following arthroscopic anterior cruciate ligament reconstruction. In contrast, intra-articular morphine does appear to be effective for decreasing postoperative pain.
关节内注射麻醉剂已被证明在膝关节镜检查后能有效缓解疼痛。但这种效果是短暂的。美沙酮血清半衰期长（35小时，而吗啡为2小时），可能会提供更好且更持久的疼痛缓解效果。本研究的目的是探讨关节内注射美沙酮对关节镜下前交叉韧带重建术后镇痛的影响。
65例骨骼成熟且接受初次前交叉韧带重建的患者被随机分为三组，三组在手术结束时均接受了由9.5 mL 0.5%布比卡因与1:200,000肾上腺素组成的关节内注射。此外，注射器中剩余的0.5 mL填充三种物质之一。研究组（25例患者）接受5 mg美沙酮，对照组（21例患者）接受5 mg吗啡，而对照组（19例患者）接受0.5 mL盐溶液。所有补充性镇痛药物均按需给药，记录并换算为吗啡等效剂量。所测量的特定变量包括住院期间和门诊期间（从出院至术后第7天）的补充镇痛需求以及疼痛评分。
美沙酮组（第1组）和对照组（第3组）在住院期间（p = 0.998）或门诊期间（p = 0.887）的补充镇痛需求或疼痛评分无显著差异。与对照组（第3组）相比，吗啡组（第2组）在住院期间（p = 0.014）和门诊期间（p = 0.044）所需的补充镇痛明显更少。无并发症发生。
本报告是关于关节内使用美沙酮的首次已知研究，并确定单次剂量5 mg这种镇痛药是安全的。然而，在此剂量下，美沙酮在关节镜下前交叉韧带重建术后并未提供更好的镇痛效果。相比之下，关节内注射吗啡似乎对减轻术后疼痛有效。
