Abstract：
The correlation between propofol concentration in exhaled breath (CE) and plasma (CP) has been well-established, but its applicability for estimating the concentration in brain tissues (CB) remains unknown. Given the impracticality of directly sampling human brain tissues, rats are commonly used as a pharmacokinetic model due to their similar drug-metabolizing processes to humans. In this study, we measuredCE,CP, andCBin mechanically ventilated rats injected with propofol. Exhaled breath samples from the rats were collected every 20 s and analyzed using our team\'s developed vacuum ultraviolet time-of-flight mass spectrometry. Additionally, femoral artery blood samples and brain tissue samples at different time points were collected and measured using high-performance liquid chromatography mass spectrometry. The results demonstrated that propofol concentration in exhaled breath exhibited stronger correlations with that in brain tissues compared to plasma levels, suggesting its potential suitability for reflecting anesthetic action sites\' concentrations and anesthesia titration. Our study provides valuable animal data supporting future clinical applications.
摘要：
呼出气（CE）和血浆（CP）中的丙泊酚浓度之间的相关性已得到很好的确立，但是其用于估计脑组织（CB）中的浓度的适用性仍然未知。鉴于直接采样人体脑组织是不切实际的，由于其与人类相似的药物代谢过程，大鼠通常被用作药代动力学模型。在这项研究中,我们测量了CE，CP,注射异丙酚的机械通气大鼠和CB。每20秒收集一次大鼠的呼气样本，并使用我们团队开发的真空紫外飞行时间质谱（VUVTOF-MS）进行分析。此外,收集不同时间点的股动脉血样和脑组织样本,采用高效液相色谱-质谱联用技术进行检测.结果表明，与血浆水平相比，呼出气中丙泊酚的浓度与脑组织中的浓度具有更强的相关性，表明它可能适合反映麻醉作用部位的浓度和麻醉滴定。我们的研究提供了有价值的动物数据，支持未来的临床应用。
