Zoratto Dana, Phelan Rachel, Hopman Wilma M, Wood Gavin C A, Shyam Vidur, DuMerton Deborah, Shelley Jessica, McQuaide Sheila, Kanee Lauren, Ho Anthony M-H, McMullen Michael, Armstrong Mitch, Mizubuti Glenio B
Department of Anesthesiology and Perioperative Medicine, Queen's University, Victory 2 Kingston General Hospital site, Kingston Health Sciences Centre, 76 Stuart Street, Kingston, ON, K7L 2V7, Canada.
Kingston General Hospital Research Institute, Kingston Health Sciences Centre, Kingston, ON, Canada.
Can J Anaesth. 2021 Jul;68(7):1028-1037. doi: 10.1007/s12630-021-01985-5. Epub 2021 May 26.
Postoperative analgesia following total knee arthroplasty (TKA) often includes intrathecal opioids, periarticular injection (PAI) of local anesthetic, systemic multimodal analgesia, and/or peripheral nerve blockade. The adductor canal block (ACB) provides analgesia without muscle weakness and magnesium sulphate (MgSO) may extend its duration. The purpose of this trial was to compare the duration and quality of early post-TKA analgesia in patients receiving postoperative ACB (± MgSO) in addition to standard care.
Elective TKA patients were randomized to: 1) sham ACB, 2) ropivacaine ACB, or 3) ropivacaine ACB with added MgSO. All received spinal anesthesia with intrathecal morphine, intraoperative PAI, and multimodal systemic analgesia. Patients and assessors remained blinded to allocation. Anesthesiologists knew whether patients had received sham or ACB but were blinded to MgSO The primary outcome was time to first analgesic (via patient-controlled analgesia [PCA] with iv morphine) following ACB. Secondary outcomes were morphine consumption, side effects, visual analogue scale pain scores, satisfaction until 24 hr postoperatively, and length of stay.
Of 130 patients, 121 were included. Nine were excluded post randomization: four were protocol violations, three did not meet inclusion criteria, and two had severe pain requiring open label blockade. There were no differences in the median [interquartile range] time to first PCA request: sham, 310 min [165-550]; ropivacaine ACB, 298 min [120-776]; and ropivacaine ACB with MgSO, 270 min [113-780] (P = 0.96). Similarly, we detected no differences in resting pain, opioid consumption, length of stay, or associated side effects until 24 hr postoperatively.
We found no analgesic benefit of a postoperative ACB, with or without added MgSO, in TKA patients undergoing spinal anesthesia and receiving intrathecal morphine, an intraoperative PAI, and multimodal systemic analgesia.
www.clinicaltrials.gov (NCT02581683); registered 21 October 2015.
全膝关节置换术（TKA）后的术后镇痛通常包括鞘内注射阿片类药物、关节周围注射（PAI）局部麻醉药、全身多模式镇痛和/或外周神经阻滞。收肌管阻滞（ACB）可提供镇痛效果且不会导致肌肉无力，硫酸镁（MgSO）可能会延长其持续时间。本试验的目的是比较在接受标准护理的基础上，接受术后ACB（±MgSO）的TKA患者术后早期镇痛的持续时间和质量。
择期TKA患者被随机分为：1）假ACB组，2）罗哌卡因ACB组，或3）添加MgSO的罗哌卡因ACB组。所有患者均接受鞘内吗啡脊髓麻醉、术中PAI和多模式全身镇痛。患者和评估者对分组情况不知情。麻醉医生知道患者接受的是假阻滞还是ACB，但对MgSO不知情。主要结局是ACB后首次使用镇痛药物（通过静脉注射吗啡的患者自控镇痛[PCA]）的时间。次要结局包括吗啡用量、副作用、视觉模拟评分法疼痛评分、术后24小时内的满意度以及住院时间。
130例患者中，121例被纳入研究。9例在随机分组后被排除：4例违反方案，3例不符合纳入标准，2例因疼痛严重需要开放标签阻滞。首次PCA请求的中位[四分位间距]时间无差异：假阻滞组为310分钟[165 - 550]；罗哌卡因ACB组为298分钟[120 - 776]；添加MgSO的罗哌卡因ACB组为270分钟[113 - 780]（P = 0.96）。同样，在术后24小时内，我们未发现静息痛、阿片类药物用量、住院时间或相关副作用方面存在差异。
我们发现，对于接受脊髓麻醉、鞘内注射吗啡、术中PAI和多模式全身镇痛的TKA患者，术后ACB无论是否添加MgSO均无镇痛益处。
