Department of Anesthesiology, Liaocheng People's Hospital, No. 67. Dongchang West Road, Liaocheng, Shandong, 252000, China.
Department of Neurosurgery, Liaocheng Brain Hospital affiliated Liaocheng People's Hospital, No. 45. Huashan Road, Liaocheng, Shandong, 252000, China.
BMC Anesthesiol. 2024 Feb 29;24(1):85. doi: 10.1186/s12871-024-02466-0.
Flash visual evoked potential (FVEP) is a critical method for monitoring intraoperative visual function during neurosurgery. A new benzodiazepine drug called remimazolam has recently been used for general anesthesia. However, the impact of remimazolam on FVEP remains unclear. Therefore, we aimed to investigate how remimazolam, in comparison to propofol, when combined with 0.6% sevoflurane anesthesia, affects the FVEP waveform during pituitary adenoma resection.
Overall, 36 patients undergoing pituitary adenoma resection under general anesthesia were randomly assigned to either the remimazolam group (Group R) or the propofol group (Group P) in a prospective, randomized, controlled, non-inferiority trial. For anesthesia induction, a bolus of 0.2 mg/kg remimazolam or 2 mg/kg propofol was intravenously infused for approximately one minute. The anesthesia was maintained by continuous infusion of either remimazolam (0.7-1.0 mg/kg/h) or propofol (4-6 mg/kg/h), in combination with 0.6% sevoflurane, aimed at sustaining the bispectral index (BIS) within the range of 40-60. The primary outcome was the N75-P100 amplitude of FVEP recorded at approximately 20 min after intubation (T0). 10% of the amplitude at T0 in group P was defined as the non-inferiority margin (δ). Confidence interval testing was used to evaluate the non-inferiority hypothesis. The secondary outcomes covered the P100 latency of FVEP, electroretinogram (ERG) b wave amplitude, demographic characteristics, hemodynamics, and occurrence of adverse events.
The BIS index during anesthesia was comparable between the groups at the same measured time points (P > 0.05). The N75-P100 amplitude at T0 in group R was 7.64 ± 1.36 µV, while it was 6.96 ± 0.95 µV in group P (P = 0.09), with a mean difference of 0.68 µV (95% CI, -0.11 µV to 1.48 µV). The δ was set at 0.7 and the lower limit of the 95% CI exceeded the -δ. Both remimazolam and propofol had little effect on ERG b-wave amplitudes. At the designated time points, FVEP amplitude and P100 latency displayed no appreciable variation between the two groups (P > 0.05). Furthermore, there were no significant differences in the incidence of adverse events related to anesthesia, needle electrodes, or surgery between the two groups (P > 0.05).
Our findings suggest that remimazolam-0.6% sevoflurane is non-inferior to propofol-0.6% sevoflurane for general anesthesia, based on the FVEP N75-P100 amplitude. The electrophysiological data obtained in both groups indicate that reproducible and stable FVEP and ERG waveforms can be acquired at set time points. Therefore, for reliable FVEP monitoring, remimazolam-0.6% sevoflurane appears to be a safe and effective protocol in general anesthesia.
This study was registered on chictr.org.cn (ChiCTR2200056803, 17/02/2022).
闪光视觉诱发电位（FVEP）是术中监测神经外科手术期间视觉功能的关键方法。一种名为瑞马唑仑的新型苯二氮䓬类药物最近已用于全身麻醉。然而，瑞马唑仑对 FVEP 的影响尚不清楚。因此，我们旨在研究瑞马唑仑与丙泊酚联合 0.6%七氟醚麻醉时，对垂体腺瘤切除术中 FVEP 波形的影响。
本前瞻性、随机、对照、非劣效性试验共纳入 36 例行垂体腺瘤切除术的全身麻醉患者，随机分为瑞马唑仑组（R 组）和丙泊酚组（P 组）。麻醉诱导时，静脉输注 0.2mg/kg 瑞马唑仑或 2mg/kg 丙泊酚，持续约 1 分钟。麻醉维持采用瑞马唑仑（0.7-1.0mg/kg/h）或丙泊酚（4-6mg/kg/h）持续输注，联合 0.6%七氟醚，使脑电双频指数（BIS）维持在 40-60 之间。主要结局为插管后约 20min（T0）记录的 FVEP 的 N75-P100 振幅。P 组 T0 时振幅的 10%定义为非劣性边界（δ）。置信区间检验用于评估非劣效性假设。次要结局包括 FVEP 的 P100 潜伏期、视网膜电图（ERG）b 波振幅、人口统计学特征、血流动力学和不良事件的发生。
两组在同一测量时间点的 BIS 指数无统计学差异（P＞0.05）。R 组 T0 时 N75-P100 振幅为 7.64±1.36µV，P 组为 6.96±0.95µV（P=0.09），平均差异为 0.68µV（95%CI，-0.11µV 至 1.48µV）。δ设定为 0.7，95%CI 的下限超过-δ。瑞马唑仑和丙泊酚对 ERG b 波振幅均无明显影响。在指定时间点，两组 FVEP 振幅和 P100 潜伏期无明显变化（P＞0.05）。此外，两组在与麻醉、针电极或手术相关的不良事件发生率方面无统计学差异（P＞0.05）。
根据 FVEP N75-P100 振幅，我们的研究结果表明，瑞马唑仑-0.6%七氟醚在全身麻醉方面不劣于丙泊酚-0.6%七氟醚。两组的电生理数据表明，在设定的时间点可以获得可重复和稳定的 FVEP 和 ERG 波形。因此，对于可靠的 FVEP 监测，瑞马唑仑-0.6%七氟醚似乎是全身麻醉中一种安全有效的方案。
本研究在中国临床试验注册中心注册（ChiCTR2200056803，2022 年 2 月 17 日）。
