Minimal Alveolar Concentration of Sevoflurane Inducing Isoelectric Electroencephalogram
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 31
- 试验地点
- 1
- 主要终点
- MACie
研究概览
简要总结
Sevoflurane can abolish movement or adrenergic response to noxious stimulus. In order to investigate the effect of sevoflurane on cerebral electrical activity, we determined the MAC of sevoflurane inducing isoelectric electroencephalogram (EEG) in 50% of the subjects (MACie) in middle aged subjects.
详细描述
Patients received sevoflurane for anesthesia induction and maintenance at preselected concentrations according to an 'up and down' design, with 0.2% as a stepsize. General anesthesia was induced and maintained with sevoflurane, tracheal intubation was facilitated with cisatracurium. After a steady-state period of 30min without surgical stimulation, the state of isoelectric EEG was considered as significant when a burst suppression ratio of 100% last for more than 1 min. The haemodynamic responses to skin incision and the vasopressor requirement to maintain cardiovascular system were also analysed according to the EEG state.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 45 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •upper abdominal surgery in general anaesthesia
- •ASA physical status classification of I or II
排除标准
- •neurological disease
- •received central nervous system-active drugs
- •cardiac ejection fraction less than 40%
- •history of difficult intubation or anticipated difficult intubation
- •daily alcohol consumption
- •obesity, defined as a body-mass index of more than 30
- •without informed consent
研究组 & 干预措施
Sevoflurane
Anaesthesia was induced by 8% sevoflurane. Cisatracurium 0.15mg kg-1 was administered after loss of the lash reflex, then ventilated manually until the amplitude of T1 decreased to 0. Intubation was performed and switched to mechanical ventilation with a fresh gas flow 2L min-1. Gas concentrations were analysed using a gas analyser.The end-tidal concentration of carbon dioxide was maintained at 4.7kPa; an esophageal temperature probe was inserted and a warming unit was used if necessary to maintain normothermia (35.5°-38.5°). The surgical incision was performed at least 30min after tracheal intubation. When arterial blood pressure (MAP) decrease exceeding 20% of baseline values. Phenylephrine 0.1mg was administered intravenously if necessary to maintained MAP and recorded.
干预措施: Sevoflurane (Drug)
结局指标
主要结局
MACie
时间窗: 30min
Minimal Alveolar Concentration of sevoflurane inducing isoelectric electroencephalogram (EEG) in 50% of the subjects (MACie)
次要结局
- MACbs(30 min)
研究者
Wei Mei
AssociateProfessor
Huazhong University of Science and Technology