Hann H C, Hall A P, Raphael J H, Langton J A
University Department of Anaesthesia, Leicester Royal Infirmary, UK.
Intensive Care Med. 1998 Aug;24(8):791-4. doi: 10.1007/s001340050667.
Patients in intensive care are known to be prone to both upper and lower respiratory tract infection. Respiratory mucus forms a barrier to infection. Mucus transport rate (MTR) depends upon both the physical properties of mucus and the action of respiratory cilia. Patients undergoing anaesthesia are known to have a reduced MTR that may be related to a depressant effect on cilia beat frequency (CBF) by anaesthetic drugs. The aim of this study was to investigate the effects of two commonly used intensive care sedative agents, midazolam and propofol, on CBF using human nasal turbinate explants in vitro.
We exposed ciliated tissue from human nasal turbinate explants to midazolam and propofol in supraclinical concentrations (20 microM midazolam and 70 microM propofol) in a controlled and blinded manner for 90 min and measured CBF by the transmitted light technique.
After 90 min, mean (SEM) CBF in the group exposed to midazolam and its control group were 13.0 (0.2) Hz and 12.9 (0.3) Hz, respectively. Mean (SEM) CBF in the group exposed to propofol was 13.6 (0.4) Hz and in the control group the value was 12.0 (0.6) Hz. There was no significant change in CBF (midazolam: p = 0.21, propofol: p = 0.31, MANOVA for repeated measures).
We have found no effect of midazolam or propofol in supra-clinical concentrations upon CBF in human turbinate explants after a 90-min exposure. This contrasts with previous work that has shown a depressant effect of inhalational anaesthetic agents on CBF.
众所周知，重症监护病房的患者易发生上呼吸道和下呼吸道感染。呼吸道黏液形成一道抗感染屏障。黏液转运速率（MTR）取决于黏液的物理特性和呼吸道纤毛的作用。已知接受麻醉的患者MTR降低，这可能与麻醉药物对纤毛摆动频率（CBF）的抑制作用有关。本研究的目的是使用人鼻甲外植体在体外研究两种常用的重症监护镇静剂咪达唑仑和丙泊酚对CBF的影响。
我们以对照和盲法将人鼻甲外植体的纤毛组织暴露于超临床浓度（20微摩尔咪达唑仑和70微摩尔丙泊酚）的咪达唑仑和丙泊酚中90分钟，并通过透射光技术测量CBF。
90分钟后，暴露于咪达唑仑组及其对照组的平均（标准误）CBF分别为13.0（0.2）赫兹和12.9（0.3）赫兹。暴露于丙泊酚组的平均（标准误）CBF为13.6（0.4）赫兹，对照组的值为12.0（0.6）赫兹。CBF无显著变化（咪达唑仑：p = 0.21，丙泊酚：p = 0.31，重复测量的多变量方差分析）。
我们发现，超临床浓度的咪达唑仑或丙泊酚在暴露90分钟后对人鼻甲外植体的CBF没有影响。这与之前显示吸入麻醉剂对CBF有抑制作用的研究结果形成对比。
