Department of Anesthesiology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
BMC Anesthesiol. 2023 Sep 25;23(1):325. doi: 10.1186/s12871-023-02275-x.
Intrathecal dexmedetomidine, as an adjuvant to local anesthetics, has been reported to improve the quality of spinal anesthesia and reduce the required local anesthetic dose. However, the optimal dosage regimen for intrathecal dexmedetomidine combined with plain ropivacaine for cesarean section (CS) remains undetermined. The present study aimed to determine the median effective dose (ED) of intrathecal dexmedetomidine as an adjuvant to plain ropivacaine for spinal anesthesia during CS.
Sixty parturients undergoing CS were randomly assigned to either group: plain ropivacaine 8 mg (Group Rop) or plain ropivacaine 10 mg (Group Rop). The initial dosage of intrathecal dexmedetomidine in each group was 5 µg. The effective dose was defined as a bilateral sensory block at the level of T6 or above to pinprick attained within 10 min after intrathecal injection, without the need for supplementary intraoperative epidural anesthesia. Effective or ineffective responses were determined, followed by a 1 µg increment or decrement in the dose of intrathecal dexmedetomidine for the next parturient using up-down sequential allocation. ED were calculated using probit regression.
The ED of intrathecal dexmedetomidine with plain ropivacaine was 5.9 µg (95% confidence interval [CI], 4.9-7.4 µg) in Group Rop and 3.1 µg (95% CI, 0.1-4.8 µg) in Group Rop (P < 0.05). Hemodynamic stability, side effects, patient satisfaction and neonatal outcomes were comparable between the two groups.
The present data suggested that the ED of intrathecal dexmedetomidine as an adjuvant to 8 mg and 10 mg plain ropivacaine in spinal anesthesia during cesarean section was approximately 6 µg and 3 µg, respectively.
Chinese Clinical Trial Registry, identifier: ChiCTR2200055928.
鞘内给予右美托咪定作为局部麻醉剂的辅助用药，已被报道可改善椎管内麻醉质量并减少所需的局部麻醉药剂量。然而，鞘内给予右美托咪定联合布比卡因行剖宫产术（CS）的最佳剂量方案仍未确定。本研究旨在确定鞘内给予右美托咪定作为布比卡因辅助用药时用于 CS 椎管内麻醉的中效剂量（ED）。
60 例行 CS 的产妇被随机分配至布比卡因 8mg 组（Rop 组）或布比卡因 10mg 组（Rop 组）。每组鞘内初始给予右美托咪定 5μg。有效剂量定义为鞘内注药后 10min 内达到双侧 T6 或以上皮区痛觉阻滞，无需术中补充硬膜外麻醉。根据有无有效反应，确定下一位产妇的剂量为鞘内给予右美托咪定 1μg 增量或减量，并采用上下序贯分配法进行分配。采用概率单位回归法计算 ED。
Rop 组和 Rop 组鞘内给予右美托咪定的 ED 分别为 5.9μg（95%置信区间[CI]，4.9-7.4μg）和 3.1μg（95%CI，0.1-4.8μg）（P<0.05）。两组产妇的血流动力学稳定性、不良反应、患者满意度和新生儿结局无差异。
本研究数据提示，8mg 和 10mg 布比卡因联合鞘内给予右美托咪定用于 CS 椎管内麻醉的 ED 分别约为 6μg 和 3μg。
中国临床试验注册中心，编号：ChiCTR2200055928。
