To explore the effects of intravenous anesthesia with remifentanil combined with midazolam on the operation time of endoscopic submucosal dissection (ESD)/endoscopic mucosal resection (EMR), the accuracy of endoscopic operation and the evaluation of submucosal injection diffusion imaging.

A total of 100 patients who underwent ESD/EMR in the Second Hospital of Tianjin Medical University from January 2023 to January 2025 were selected, and the patients were divided into the control group and the observation group, each with 50 cases, by using the method of randomized numerical table. The control group was given propofol combined with remifentanil intravenous anesthesia, and the observation group was given remifentanil combined with midazolam intravenous anesthesia. The two groups were compared in terms of surgery-related indexes, endoscopic operation precision, submucosal injection diffusion image assessment, hemodynamic indexes [mean arterial pressure (MAP), heart rate (HR)] before and after anesthesia, serum stress indexes [cortisol, norepinephrine (NE), epinephrine (E)] levels and the incidence of adverse reactions.

The operation time of the observation group was shorter than that of the control group (P<0.05). The excellent rate of endoscopic operation precision and the good rate of submucosal injection diffusion in the observation group were higher than those in the control group (P<0.05). At 10 min after anesthesia and at the end of surgery, the MAP and HR of the two groups were lower than that before anesthesia, and the values of the observation group was lower than that of the control group (P<0.05). The serum cortisol, NE, and E levels in both groups were higher than those before anesthesia, and the levels in the observation group were lower than those in the control group (P<0.05). The incidence of adverse reactions in the observation group was lower than that in the control group (P<0.05).

Remifentanil combined with midazolam intravenous anesthesia for ESD/EMR can shorten the surgical operation time, improve the endoscopic operation precision, optimize the submucosal injection diffusion image assessment, stabilize the hemodynamic indexes, and reduce the body's stress response, and has a higher safety profile.