The assessment on the mechanism of occurrence of postoperative delirium mechanism

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K11079
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Anesthesiology
• Research Institution: Kobe University
• Principal Investigator: Okada Masako 神戸大学, 医学部附属病院, 助教 (00622549)
• Co-Investigator(Kenkyū-buntansha): 江木 盛時 神戸大学, 医学研究科, 准教授 (20423296)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: せん妄 / トリプトファン代謝物質 / 心臓血管外科手術

Outline of Final Research Achievements

As a Pilot study, we examined the perioperative changes of serum tryptophan and serotonin level. It was clarified that the serum serotonin/tryptophan concentration immediately after the operation did not significantly change compared with that before the operation.
We investigated the mechanism of delirium development within 96 hours after thoracoabdominal aortic replacement surgery from the viewpoint of tryptophan metabolites. In patients with thoracoabdominal aortic replacement, the levels of serum S100β, serum NSE, and total tau protein in cerebrospinal fluid, which were biomarkers of neuropathies, increased after surgery. The COVID-19 epidemic has delayed the measurement of tryptophan/serotonin/melatonin. After the measuring device can be used normally, tryptophan/serotonin/melatonin will be measured and final analysis will be performed.

Free Research Field

麻酔科学

Academic Significance and Societal Importance of the Research Achievements

術後のせん妄は心臓大血管手術において約30％に発生し、死亡率の上昇や入院期間の延長と関係する。せん妄発生の予防が重要であるが、発生機序が不明なため確立された予防法は存在しない。今回の対象患者でも40％の患者において術後せん妄が認められた。周術期せん妄発生機序として手術・麻酔によって生じるトリプトファンの代謝異常が関与している可能性があれば、術後せん妄予防としての周術期アミノ酸投与など、新しい術後せん妄予防法の開発につながる可能性がある。