Pain caused by laparoscopic surgery: elucidation of the mechanism underlying Intra- and post-operative pain and identification of effective analgesia using a rat model.

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K18268
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 55050:Anesthesiology-related
• Research Institution: Shinshu University
• Principal Investigator: Nakamura Hiroyuki 信州大学, 医学部附属病院, 助教(診療) (20838370)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 気腹 / 疼痛

Outline of Final Research Achievements

To reproduce the laparoscopic surgical environment, general anaesthesia was induced in young rats by inhalation of sevoflurane, followed by oral intubation and controlled breathing. After approximately 1 h of insufflation (carbon dioxide, 0.2 mH2O), pain was assessed after awakening, We attempted to uniform the experimental conditions by considering stress from changes in ambient temperature and body temperature, hypercarbolaemia, etc. as possible causes of freezing, but it was difficult to do so. On the other hand, these variations reflected actual clinical conditions well, indicating the usefulness of the pneumoperitoneum as a model for pneumoperitoneum.

Free Research Field

麻酔・疼痛領域

Academic Significance and Societal Importance of the Research Achievements

腹腔鏡手術は一般的に開腹手術と比べ身体への負担が少ない手術として知られるが、腹腔内の気腹ガス（主に二酸化炭素）への暴露が長時間に及ぶことで体熱喪失、腹腔内の乾燥、酸性化、無気肺、循環動態への負荷などさまざまな影響が生じうる。特に腹腔内の乾燥や酸性化は疼痛への影響が示唆されている。今回作成した気腹モデルラットでも実臨床に則した状況が再現されており、本モデル動物を活用することで、より望ましい気腹条件の検討に役立つ可能性がある。