The association between intraoperative anesthesia methods used during gastric cancer surgery and long-term mortality: A retrospective observational study using a Japanese claims database

Purpose Various basic and clinical studies have investigated the association between the types of anesthetic agents and prognosis. However, the results have varied among studies and remain controversial. In the present study, we aimed to investigate whether the risk of all-cause mortality differs between inhaled or intravenous anesthetics in patients with gastric cancer undergoing gastrectomy. Methods Using a Japanese nationwide insurance claims database, we analyzed patients who underwent gastrectomy under general anesthesia for gastric cancer between January 2005 and September 2019. Postoperative outcomes were compared between two groups: those who received inhaled anesthetics (Sevoflurane, Isoflurane, or Desflurane) and those who received intravenous anesthetics (propofol), using a multivariable Cox proportional hazards model. The primary outcome was overall survival. Results Among 2671 eligible patients, 2105 were in the inhaled anesthetic group, and 566 were in the intravenous anesthetic group. The median (interquartile range) age was 58 (51-63) years, and 1979 (74.1%) were men. The median follow-up period was 795 days. We identified 56 (2.7%) and 16 (2.8%) deaths during the follow- up period in the inhaled and intravenous anesthetic use groups, respectively. There was no difference in postoperative overall survival between the two groups (hazard ratio, 0.97; 95% confidence interval, 0.56-1.70; P = 0.93). Conclusions We found no significant difference in the postoperative risks of overall survival between inhaled and intravenous anesthesia in patients with gastric cancer undergoing gastrectomy.