Epinephrine-induced Effects on Cerebral Microcirculation and Oxygenation Dynamics Using Multimodal Monitoring and Functional Photoacoustic Microscopy

作者：Dong Zhang, Wei Wang, Xiaoyi Zhu, Ran Li, Wei Liu, Maomao Chen, Tri Vu, Laiming Jiang, Qifa Zhou, Cody L. Evans, Dennis A. Turner, Huaxin Sheng, Jerrold H. Levy, Jianwen Luo, Wei Yang, Junjie Yao, Ulrike Hoffmann · 发表于：Anesthesiology · 年份：2023 · DOI：10.1097/aln.0000000000004592 · 被引用次数：16 · 研究领域：Photoacoustic and Ultrasonic Imaging、Traumatic Brain Injury and Neurovascular Disturbances、Cardiac Arrest and Resuscitation

BACKGROUND: The administration of epinephrine after severe refractory hypotension, shock, or cardiac arrest restores systemic blood flow and major vessel perfusion but may worsen cerebral microvascular perfusion and oxygen delivery through vasoconstriction. The authors hypothesized that epinephrine induces significant microvascular constriction in the brain, with increased severity after repetitive dosing and in the aged brain, eventually leading to tissue hypoxia. METHODS: The authors investigated the effects of intravenous epinephrine administration in healthy young and aged C57Bl/6 mice on cerebral microvascular blood flow and oxygen delivery using multimodal in vivo imaging, including functional photoacoustic microscopy, brain tissue oxygen sensing, and follow-up histologic assessment. RESULTS: The authors report three main findings. First, after epinephrine administration, microvessels exhibited severe immediate vasoconstriction (57 ± 6% of baseline at 6 min, P < 0.0001, n = 6) that outlasted the concurrent increase in arterial blood pressure, while larger vessels demonstrated an initial increase in flow (108 ± 6% of baseline at 6 min, P = 0.02, n = 6). Second, oxyhemoglobin decreased significantly within cerebral vessels with a more pronounced effect in smaller vessels (microvessels to 69 ± 8% of baseline at 6 min, P < 0.0001, n = 6). Third, oxyhemoglobin desaturation did not indicate brain hypoxia; on the contrary, brain tissue oxygen increased after epinephrine applic...