Department of Anesthesiology and Intensive Care, University of Rostock, Schillingallee 35, 18057 Rostock, Germany.
Anal Bioanal Chem. 2011 Oct;401(7):2093-102. doi: 10.1007/s00216-011-5099-8. Epub 2011 Jun 4.
Breath analysis could offer a non-invasive means of intravenous drug monitoring if robust correlations between drug concentrations in breath and blood can be established. In this study, propofol blood and breath concentrations were determined in an animal model under varying physiological conditions. Propofol concentrations in breath were determined by means of two independently calibrated analytical methods: continuous, real-time proton transfer reaction mass spectrometry (PTR-MS) and discontinuous solid-phase micro-extraction coupled with gas chromatography mass spectrometry (SPME-GC-MS). Blood concentrations were determined by means of SPME-GC-MS. Effects of changes in pulmonary blood flow resulting in a decreased cardiac output (CO) and effects of dobutamine administration resulting in an increased CO on propofol breath concentrations and on the correlation between propofol blood and breath concentrations were investigated in seven acutely instrumented pigs. Discontinuous propofol determination in breath by means of alveolar sampling and SPME-GC-MS showed good agreement (R(2)=0.959) with continuous alveolar real-time measurement by means of PTR-MS. In all investigated animals, increasing cardiac output led to a deterioration of the relationship between breath and blood propofol concentrations (R(2)=0.783 for gas chromatography-mass spectrometry and R(2)=0.795 for PTR-MS). Decreasing pulmonary blood flow and cardiac output through banding of the pulmonary artery did not significantly affect the relationship between propofol breath and blood concentrations (R(2)>0.90). Estimation of propofol blood concentrations from exhaled alveolar concentrations seems possible by means of different analytical methods even when cardiac output is decreased. Increases in cardiac output preclude prediction of blood propofol concentration from exhaled concentrations.
如果能够建立呼吸中药物浓度与血液中药物浓度之间的稳健相关性，呼吸分析可能为静脉内药物监测提供一种非侵入性手段。在这项研究中，在不同生理条件下，在动物模型中确定了丙泊酚的血液和呼吸浓度。通过两种独立校准的分析方法来确定呼吸中的丙泊酚浓度：连续实时质子转移反应质谱（PTR-MS）和不连续固相微萃取与气相色谱质谱联用（SPME-GC-MS）。通过 SPME-GC-MS 确定血液浓度。研究了肺血流量变化导致心输出量（CO）减少以及多巴酚丁胺给药导致 CO 增加对丙泊酚呼吸浓度和丙泊酚血液与呼吸浓度之间相关性的影响，在七只急性仪器化猪中进行了研究。通过肺泡采样和 SPME-GC-MS 对呼吸中丙泊酚的不连续测定与通过 PTR-MS 进行的连续肺泡实时测定具有良好的一致性（R（2）=0.959）。在所有研究的动物中，心输出量增加导致呼吸和血液中丙泊酚浓度之间的关系恶化（GC-MS 的 R（2）=0.783，PTR-MS 的 R（2）=0.795）。通过肺动脉带束减少肺血流量和心输出量不会显著影响丙泊酚呼吸和血液浓度之间的关系（R（2）>0.90）。即使心输出量降低，通过不同的分析方法，似乎也可以从呼出的肺泡浓度估算丙泊酚的血液浓度。心输出量增加排除了从呼出浓度预测血液中丙泊酚浓度的可能性。
