Sakota Daisuke, Kosaka Ryo, Niikawa Hiromichi, Ohuchi Katsuhiro, Arai Hirokuni, McCurry Kenneth R, Okamoto Toshihiro
Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 3058564, Japan.
Department of Thoracic Surgery, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi 9808575, Japan.
Biomed Opt Express. 2021 Dec 14;13(1):328-343. doi: 10.1364/BOE.445021. eCollection 2022 Jan 1.
Ex vivo lung perfusion (EVLP) is an emerging tool to evaluate marginal lungs in lung transplantation. However, there is no objective metric to monitor lobular regional oxygenation during EVLP. In this study, we developed oxygen saturation (SaO) imaging to quantitatively assess the regional gas exchange potential of the lower lobes. Ten porcine lungs were randomly divided into control and donation after circulatory death (DCD) groups (n = 5, each). Lungs were perfused in cellular EVLP for 2 h, and multispectral images were continuously collected from the dorsal sides of the lower lobes. We examined whether lower lobe SaO correlated with PaO/FiO (P/F) ratios in lower pulmonary veins (PV). The wet/dry ratio in lower lobes was measured and Monte Carlo simulations were performed to investigate the method's feasibility. There was a significant correlation between lower lobe SaO and the P/F ratio in lower PV (r = 0.855, < 0.001). The DCD group was associated with lower SaO and higher wet/dry ratio than the control group ( < 0.001). The error of estimated SaO was limited according to Monte Carlo simulations. The developed technology provides a noninvasive and regional evaluative tool of quantitative lobular function in EVLP.
体外肺灌注（EVLP）是一种用于评估肺移植中边缘供肺的新兴工具。然而，在体外肺灌注过程中，尚无客观指标来监测小叶区域的氧合情况。在本研究中，我们开发了血氧饱和度（SaO）成像技术，以定量评估下叶的区域气体交换潜力。将10个猪肺随机分为对照组和循环死亡后供体（DCD）组（每组n = 5）。在细胞性体外肺灌注中对肺进行灌注2小时，并从下叶背侧连续采集多光谱图像。我们研究了下叶SaO是否与下肺静脉（PV）中的PaO/FiO（P/F）比值相关。测量下叶的湿/干比，并进行蒙特卡洛模拟以研究该方法的可行性。下叶SaO与下肺静脉中的P/F比值之间存在显著相关性（r = 0.855，P < 0.001）。与对照组相比，DCD组的SaO较低，湿/干比更高（P < 0.001）。根据蒙特卡洛模拟，估计的SaO误差有限。所开发的技术为体外肺灌注中的小叶功能提供了一种无创的区域评估工具。
