Crystallization of Local Anesthetic and Adjuvant Mixtures in Cerebrospinal Fluid as a Model for Interstitial Space - a Semiquantitative in Vitro Trial
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 2
- 试验地点
- 2
- 主要终点
- Grade of Crystallisation
研究概览
简要总结
Different mixtures of local anesthetics or local anesthetics with adjuvants that are known to precipitate in vitro are tested in human cerebrospinal fluid (CSF). CSF is gained from patients with normal pressure hydrocephalus scheduled for elective lumbar puncture. Patients signed an ICF for leftover samples.
CSF will be assessed for pH values at different timepoints (t0-t3; 0 to 60 minutes).
In a second step six commonly used mixtures of LA with LA or LAs with adjuvants will be mixed using the following mixture ratios: ropivacaine 0.75% + lidocaine 2% (ratio 1:1), ropivacaine 0,75% + mepivacaine 2% (ratio 1:1), ropivacaine 0.75% + chloroprocaine 2% (ratio 1:1), lidocaine 2% + sodium bicarbonate 8.4% (ratio 1:0.1), ropivacaine 0.75% + lidocaine 2% + sodium bicarbonate 8.4% (ratio 1:1:0.1) and ropivacaine 0.75% + dexamethasone (1.5:1). The used mixture ratios are inspired by commonly mixtures described in the current literature and have been proven to precipitate in vitro. For every mixture, a Grade of Crystallisation will be determined at baseline without CSF and then at t0 (immediately) to t3 (60 minutes) every 15 minutes.
详细描述
Different mixtures of local anesthetics or local anesthetics with adjuvants that are known to precipitate in vitro are tested in human cerebrospinal fluid (CSF). CSF is gained from patients with normal pressure hydrocephalus scheduled for elective lumbar puncture. Patients signed an ICF for leftover samples.
CSF will be assessed for pH values at different timepoints (t0-t3; 0 to 60 minutes).
In a second step six commonly used mixtures of LA with LA or LAs with adjuvants will be mixed using the following mixture ratios: ropivacaine 0.75% + lidocaine 2% (ratio 1:1), ropivacaine 0,75% + mepivacaine 2% (ratio 1:1), ropivacaine 0.75% + chloroprocaine 2% (ratio 1:1), lidocaine 2% + sodium bicarbonate 8.4% (ratio 1:0.1), ropivacaine 0.75% + lidocaine 2% + sodium bicarbonate 8.4% (ratio 1:1:0.1) and ropivacaine 0.75% + dexamethasone (1.5:1). The used mixture ratios are inspired by commonly mixtures described in the current literature and have been proven to precipitate in vitro. For every mixture, a Grade of Crystallisation will be determined at baseline without CSF and then at t0 (immediately) to t3 (60 minutes) every 15 minutes.
研究设计
- 研究类型
- Observational
- 观察模型
- Other
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —(Adult, Older Adult)
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Patients with normal pressure hydrocephalus scheduled for elective lumbar puncture.
排除标准
- •Age < 18 years
研究组 & 干预措施
Patients with normal pressure hydrocephalus scheduled for elective lumbar puncture
Patients with normal pressure hydrocephalus scheduled for elective lumbar puncture
结局指标
主要结局
Grade of Crystallisation
时间窗: 1 hour
For the grading of detectable precipitations, a scale from 0 (no signs of precipitation / single particulates \< 10 μm) to 5 (heavy polymorphic crystallization: \> 100 solid bodies \> 10 μm, and \> 1 solid body \> 50 μm or \> 1 solid body \> 100 μm) will be used.
次要结局
- pH value and of CSF and CSF LA mixtures(1 hour)
- pCO2 of CSF and CSF LA mixtures(1 hour)
