Comparison of Measured Versus Predicted Blood Propofol Concentrations During Total Intravenous Anaesthesia in Children Undergoing Spinal Surgery
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 20
- 试验地点
- 1
- 主要终点
- The absolute difference between the measured and predicted concentrations of propofol in micrograms per ml of blood.
研究概览
简要总结
During major spinal surgery evoked potential monitoring is performed to detect spinal cord damage. Intra-venous anaesthesia is the preferred anaesthetic technique because volatile anaesthetic agents supress the evoked potentials. Total Intra-Venous Anaesthesia (TIVA) with propofol is commonly administered as a Target Controlled Infusion (TCI). The TCI is an automated drug delivery system which administers propofol to achieve a desired blood concentration, based on an in built pharmaco-kinetic data (TCI model) derived from previous studies. The TCI model also provides a real time predicted blood concentration to facilitate the anaesthetist to adjust the target concentration of propofol.
The TCI algorithm is based on pharmaco-kinetic data derived from previous studies in a relatively small number of patients, by a "best fit" relationship between blood levels, infusion rates and other factors (such as age and weight). Several factors make it possible for a wide discrepancy between the predicted and the true blood concentrations. This difference can be higher in children compared to adults. Also blood loss and administration of large volumes of intravenous fluids can affect the blood concentrations. This study aims to identify the difference between the predicted and true blood concentrations by using Pelorus 1500, a bedside blood propofol measurement device, in children undergoing major spinal surgery under TIVA.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 盲法
- Double (Participant, Care Provider)
入排标准
- 年龄范围
- 5 Years 至 18 Years（Child, Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Children undergoing major spinal surgery under propofol TCI
- •Surgery expecting to last more than 3 hours.
排除标准
- •Major hepatic or renal disease
研究组 & 干预措施
Single arm
The intervention in this study involves taking blood sample from an existing arterial line for measurement of blood propofol levels. The drug in evaluation is Propofol 2% (Diprivan 2%, Astra Zeneca UK) administered as a target controlled infusion using the commercially available paediatric TCI models (Paedfusor and Marsh models). The dose range is usually between a target concentration of 3-8 mcg/ml. However the anaesthetic management is not changed for the study. The blood concentrations of propofol will be measured using Pelorus 1500 (Sphere Medical, UK), a CE marked device. The anaesthetist will be blinded from the measurements, unless the measured value was outside the safe limit ( < 3 mcg/ml or > 10mcg/ml).
干预措施: Pelorus 1500 (Device)
Single arm
The intervention in this study involves taking blood sample from an existing arterial line for measurement of blood propofol levels. The drug in evaluation is Propofol 2% (Diprivan 2%, Astra Zeneca UK) administered as a target controlled infusion using the commercially available paediatric TCI models (Paedfusor and Marsh models). The dose range is usually between a target concentration of 3-8 mcg/ml. However the anaesthetic management is not changed for the study. The blood concentrations of propofol will be measured using Pelorus 1500 (Sphere Medical, UK), a CE marked device. The anaesthetist will be blinded from the measurements, unless the measured value was outside the safe limit ( < 3 mcg/ml or > 10mcg/ml).
干预措施: Propofol 2% (Diprivan 2%, Astra Zeneca UK) (Drug)
结局指标
主要结局
The absolute difference between the measured and predicted concentrations of propofol in micrograms per ml of blood.
时间窗: Up to 5 hours during the maintenance phase of anaesthesia, to allow a maximum of 10 samples at 20 to 30 min intervals.
次要结局
- Median Performance Error (MDPE)(Up to 5 hours during the maintenance phase of anaesthesia, to allow a maximum of 10 samples at 20 to 30 min intervals.)
- Median Absolute Performance Error (MDAPE)(Up to 5 hours during the maintenance phase of anaesthesia)
- Wobble(Up to 5 hours during the maintenance phase of anaesthesia)
- Divergence(Up to 5 hours during the maintenance phase of anaesthesia)