A Phase IV Study to Investigate the Effects of Varied Remifentanil Concentrations on Propofol Requirements for Loss of Consciousness, Response to Painful Stimuli, Bispectral Index and Associated Haemodynamic Changes
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 100
- 试验地点
- 1
- 主要终点
- Effect site concentration of propofol at time of loss of consciousness for each of the two groups
研究概览
简要总结
A prospective, randomised, phase IV trial including 150 patients.
To evaluate the effects of varied concentrations of remifentanil on the proposal requirements for the loss of consciousness and response to pain and to evaluate the haemodynamic changes and processed EEG (BIS) during induction of anaesthesia.
详细描述
BackGround
The combination of remifentanil and propofol infusions is a widely used method of total intravenous anaesthesia. (1) Target controlled infusion (TCI) is a pharmacokinetic (PK) infusion system using data from a large population of patients to calculate and deliver stable concentrations of a drug based on a three compartment PK model. Both propofol and remifentanil are ideal drugs for delivery in this way because of their quick distribution, metabolism and excretion. (2) Remifentanil is a potent synthetic opioid receptor (MOR) agonist with a short recovery irrespective of the duration of its administration. This is due to it being quickly broken down by non-specific esterases in blood and tissues. (3) Remifentanil like all opioids is not very hypnotic in clinically relevant concentrations. (4)
Remifentanil has been shown to reduce propofol requirements during induction and maintenance of anaesthesia. (5)(6) Also modest doses of remifentanil markedly reduce the amount of propofol required to ablate response to painful stimuli. The relationship between propofol and remifentanil has been reported as synergistic but additive when using propofol concentrations within the clinical range. (7)(8) However in other studies, BIS has shown no interaction between propofol and remifentanil (9)(10) A correlation between BIS, painful stimuli and other opioids has been demonstrated. (11) It has been suggested that BIS values can change with propofol and painful stimuli and this can aid administration of remifentanil in a dose dependent manner. (12) Since propofol and remifentanil are ubiquitously used together, the interaction between these drugs and EEG needs to be defined in more detail.
Trial Objectives To see whether remifentanil affects the dose of proposal required for loss of consciousness and loss of response to painful stimuli and whether this is reflected in changes in brain EEG (bispectral index BIS)
Hypothesis That the effect site concentration of proposal at loss of consciousness will only be moderately affected by concurrently remifentanil infusion but BIS will not change. That the clinical response to painful stimuli will markedly decrease when there is concurrent infusion of remifentanil. With painful stimuli there will be an increase in BIS but this will be blocked by remifentanil.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Triple (Participant, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •ASA I or II patients (healthy or with mild systemic illness) undergoing planned surgery requiring general anaesthetic
排除标准
- •Subjects with pre-existing neurological or psychiatric illness.
- •Subjects on CNS acting medication or analgesics.
研究组 & 干预措施
remifentanil effect site concentration 0ng/ml
remifentanil run as an infusion using the minto TCI model, at an effect site concentration of 0 nano grams per millilitre, commenced from start of proposal infusion to point at which patient is anaesthetised and not responding to painful stimuli.
干预措施: Remifentanil (Drug)
remifentanil effect site concentration 0ng/ml
remifentanil run as an infusion using the minto TCI model, at an effect site concentration of 0 nano grams per millilitre, commenced from start of proposal infusion to point at which patient is anaesthetised and not responding to painful stimuli.
干预措施: Propofol (Drug)
remifentanil effect site concentration 0ng/ml
remifentanil run as an infusion using the minto TCI model, at an effect site concentration of 0 nano grams per millilitre, commenced from start of proposal infusion to point at which patient is anaesthetised and not responding to painful stimuli.
干预措施: Bispectral index (Other)
remifentanil effect site concentration 3ng/ml
remifentanil run as an infusion using the minto TCI model, at an effect site concentration of 3 nano grams per millilitre, commenced from start of proposal infusion to point at which patient is anaesthetised and not responding to painful stimuli.
干预措施: Remifentanil (Drug)
remifentanil effect site concentration 3ng/ml
remifentanil run as an infusion using the minto TCI model, at an effect site concentration of 3 nano grams per millilitre, commenced from start of proposal infusion to point at which patient is anaesthetised and not responding to painful stimuli.
干预措施: Propofol (Drug)
remifentanil effect site concentration 3ng/ml
remifentanil run as an infusion using the minto TCI model, at an effect site concentration of 3 nano grams per millilitre, commenced from start of proposal infusion to point at which patient is anaesthetised and not responding to painful stimuli.
干预措施: Bispectral index (Other)
结局指标
主要结局
Effect site concentration of propofol at time of loss of consciousness for each of the two groups
时间窗: every 1 minute up to 40 minutes
Effect site concentration of propofol at loss of response to painful stimuli for each of the three groups
时间窗: every 1 minute up to 40 minutes
次要结局
- EEG Bispectral index BIS(every 1 minute up to 40 minutes)
- Time to loss of consciousness(every 1 minute up to 40 minutes)
- heart rate(every 1 minute up to 40 minutes)
- blood pressure(every 1 minute up to 40 minutes)
研究者
Hannah Scott
Clinical Associate
The University of Hong Kong