The effects of anesthetic agents on cerebral blood flow and cerebral matabolic ratio by near infrared spectroscopy

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K09235
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 55050:Anesthesiology-related
• Research Institution: National Cardiovascular Center Research Institute
• Principal Investigator: Yoshitani Kenji 国立研究開発法人国立循環器病研究センター, 病院, 部長 (30524029)
• Co-Investigator(Kenkyū-buntansha): 月永 晶人 国立研究開発法人国立循環器病研究センター, 病院, 客員研究員 (80867523)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 脳血流 / 麻酔薬 / 頸動脈遮断 / 近赤外線分光法 / 周波数フィルター

Outline of Final Research Achievements

We developed a method to measure regional cerebral blood flow at the bedside using indocyanine green and near-infrared spectroscopy. Using this method, we investigated the effects of inhaled and intravenous anesthetics on cerebral blood flow during carotid artery clamping in carotid endarterectomy and thoracic endovascular aortic repair with carotid artery bypass. Cerebral blood flow was significantly decreased on the clamped side during carotid artery clamping, and cerebral blood flow recovered to the baseline value after the declamping. No significant decrease in cerebral blood flow was observed with inhaled anesthetics during carotid clamping, but a significant decrease was observed with intravenous anesthetics during carotid clamping.

Free Research Field

神経麻酔、心臓麻酔、輸血学

Academic Significance and Societal Importance of the Research Achievements

静脈麻酔薬が、脳血流を低下させることは動物実験及び健常人ボランティアで報告はされていたが、術中に動脈硬化の進んだ患者で麻酔薬の脳血流に対する影響を調べた報告はこれまでにない。本来は、放射線科の施設に患者を搬送してPET、SPECTや脳灌流CTなどで脳血流を測定する必要があったが、我々の方法を用いると手術中の頸動脈遮断などの臨床現場で脳血流の測定が必要な状況で測定可能になる。今回の研究では実際に麻酔薬により脳血流に差があることが分かり、今後の臨床応用が可能になる。今後、様々な場面での活用が期待される。