Gruber Sybille, Spielauer Isabella, Böhme Stefan, Baron David, Markstaller Klaus, Ullrich Roman, Klein Klaus Ulrich
From the Department of Anaesthesia, General Intensive Care Medicine and Pain Therapy, Medical University Vienna, Austria.
Eur J Anaesthesiol. 2015 Jun;32(6):392-9. doi: 10.1097/EJA.0000000000000260.
Little is known about real-time in-vivo microscopy of pulmonary capillary perfusion because current microscopy requires direct access to lung tissue with surgical intervention such as the thoracic-window technique and open-lung model.
To evaluate if probe-based confocal laser scanning endomicroscopy (pCLE) via the trachea allows for real-time in-vivo visualisation of pulmonary capillary density and red blood cell (RBC) velocity in pigs.
An interventional animal study.
European University Hospital.
Nine female domestic pigs (50 to 60 kg) were used.
A pCLE probe was positioned in non-dependent, central and dependent lung zones in nine anaesthetised pigs (Alveoflex, Cellvizio, Maunakea, France). After intravenous administration of fluorescein isothiocyanate dextran as contrast agent repetitive pCLE videos were recorded during pressure-controlled ventilation (PCV) or continuous positive airway pressure for 3 min each. Using fluorescein isothiocyanate-labelled RBC erythrocyte velocities in pulmonary capillaries were quantified. Data are expressed as mean ± SD or median with interquartile range (IQR).
Capillary density was greater in dependent and central as compared with non-dependent lung zones [[32 (29 to 34) %] and 32 (30 to 34) % vs. 28 (26 to 28) %, respectively, P < 0.05]. During PCV, RBC velocities were higher in larger lung capillaries [diameter >20 μm, 309 μm s(-1) (209 to 397)] than intermediate [diameter 10.1 to 20 μm, 146 μm s(-1) (118 to 235)] and small [diameter <10 μm, 153 μm s(-1) (117 to 236), P < .05]. During continuous positive airway pressure of 1.5 kPa, RBC velocities in dependent lung areas decreased to 47 μm s(-1) (30 to 82) compared with 198 μm s(-1) (148 to 290) during PCV (P < 0.05).
pCLE allows endoscopic real-time in-vivo imaging of pulmonary capillary morphology and perfusion. Alterations in pulmonary capillary blood flow induced by different ventilator regimens can be detected. This minimally invasive approach via the endotracheal route is feasible in an experimental setting and may help to understand changes in regional pulmonary capillary perfusion.
由于目前的显微镜检查需要通过手术干预（如胸腔开窗技术和开胸肺模型）直接接触肺组织，因此对肺毛细血管灌注的实时体内显微镜检查了解甚少。
评估经气管的基于探头的共聚焦激光扫描内镜检查（pCLE）是否能实时体内观察猪肺毛细血管密度和红细胞（RBC）速度。
一项干预性动物研究。
欧洲大学医院。
使用9只雌性家猪（50至60千克）。
将pCLE探头置于9只麻醉猪（Alveoflex，Cellvizio，Maunakea，法国）的非下垂、中央和下垂肺区。静脉注射异硫氰酸荧光素葡聚糖作为造影剂后，在压力控制通气（PCV）或持续气道正压通气期间，每次记录3分钟的重复pCLE视频。使用异硫氰酸荧光素标记的红细胞对肺毛细血管中的红细胞速度进行量化。数据以平均值±标准差或中位数及四分位间距（IQR）表示。
与非下垂肺区相比，下垂和中央肺区的毛细血管密度更高[分别为32（29至34）%和32（30至34）%，而28（26至28）%，P<0.05]。在PCV期间，较大肺毛细血管[直径>20μm，309μm·s⁻¹（209至397）]中的红细胞速度高于中等[直径10.1至20μm，146μm·s⁻¹（118至235）]和小[直径<10μm，153μm·s⁻¹（117至236）]毛细血管（P<0.05）。在1.5kPa的持续气道正压通气期间，下垂肺区的红细胞速度降至47μm·s⁻¹（30至82），而PCV期间为198μm·s⁻¹（148至290）（P<0.05）。
pCLE可实现肺毛细血管形态和灌注的内镜实时体内成像。可检测到不同通气方案引起的肺毛细血管血流变化。这种经气管途径的微创方法在实验环境中是可行的，可能有助于了解区域肺毛细血管灌注的变化。
