Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Republic of Korea.
Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Republic of Korea
Reg Anesth Pain Med. 2019 Apr;44(4):459-465. doi: 10.1136/rapm-2018-100084. Epub 2019 Jan 23.
Fentanyl is widely used as an intrathecal adjuvant to local anesthetics to enhance the duration of spinal anesthesia. Recent evidence suggests that intravenous dexmedetomidine prolongs the duration of spinal anesthesia. This noninferiority study evaluated whether bupivacaine alone could provide a noninferior duration of block compared with bupivacaine and fentanyl when intravenous dexmedetomidine was administered intraoperatively.
Fifty-six patients scheduled for total knee arthroplasty under spinal anesthesia were randomly allocated to receive either bupivacaine 13 mg with intrathecal fentanyl 20 µg (Group BF) or bupivacaine 13 mg (Group B). Both groups underwent intravenous dexmedetomidine sedation throughout the surgery (1 µg kg for 10 min, followed by 0.5 µg kg h). The primary outcome was the time to two-segment regression of the sensory block. The noninferiority margin for the mean difference was predefined as -10 min. Secondary outcomes included postoperative pain scores, analgesics consumptions, and the incidences of pruritus, nausea, and vomiting.
There was no significant difference in the two-segment regression time of sensory block (Group B 109.1±25.0 min vs Group BF 104.3±25.9 min; p=0.484). The mean difference in the two-segment regression time between the 2 groups was 4.8 min (95 % CI -8.9 to 18.6), demonstrating the noninferiority of bupivacaine alone. Secondary outcomes showed no significant differences between the two groups.
The duration of spinal anesthesia with bupivacaine alone is noninferior to that of bupivacaine plus fentanyl in patients receiving intravenous dexmedetomidine intraoperatively. Our results suggest that intrathecal fentanyl may not be required when intravenous dexmedetomidine is administered.
NCT03105115.
芬太尼被广泛用作鞘内局部麻醉药的辅助药物，以延长椎管内麻醉的持续时间。最近的证据表明，静脉给予右美托咪定可延长椎管内麻醉的持续时间。本非劣效性研究评估了在术中给予静脉右美托咪定时，单独使用布比卡因是否可以与布比卡因和芬太尼提供非劣效的阻滞持续时间。
56 名拟行椎管内麻醉下全膝关节置换术的患者被随机分配接受布比卡因 13mg 加鞘内芬太尼 20µg（BF 组）或布比卡因 13mg（B 组）。两组患者在整个手术过程中均接受静脉右美托咪定镇静（1µg/kg 持续 10 分钟，然后 0.5µg/kg/h）。主要结局是感觉阻滞的两阶段消退时间。平均差异的非劣效性边界定义为-10 分钟。次要结局包括术后疼痛评分、镇痛药消耗以及瘙痒、恶心和呕吐的发生率。
两组感觉阻滞的两阶段消退时间无显著差异（B 组 109.1±25.0 分钟 vs BF 组 104.3±25.9 分钟；p=0.484）。两组两阶段消退时间的平均差异为 4.8 分钟（95%置信区间-8.9 至 18.6），表明单独使用布比卡因具有非劣效性。两组的次要结局无显著差异。
在术中给予静脉右美托咪定时，单独使用布比卡因的椎管内麻醉持续时间不劣于布比卡因加芬太尼。我们的结果表明，当给予静脉右美托咪定时，鞘内芬太尼可能不是必需的。
NCT03105115。
