Abstract:Objective To investigate the anaesthetic effect of oral lidocaine compounded with low-dose midazolam in obese patients underwent painless gastroscopy.Methods 120 cases of obese patients who underwent painless gastroscopy from August 2020 to October 2021 were enrolled in the study. According to the random number chart method, they were divided into a regular group, a control group and an observation group, with 40 cases in each group. The regular group was anaesthetized with sufentanil and propofol intravenously, the control group was anaesthetized with midazolam, sufentanil and propofol intravenously, and the observation group was anaesthetized with oral gargling of 2% lidocaine compounded with midazolam, sufentanil and propofol intravenously. The changes in heart rate (HR), mean arterial pressure (MAP), percutaneous arterial oxygen saturation (SpO2), and respiratory rate (RR) before anaesthesia administration (T0), at the beginning of examination (T1), at the time of gastroscopy over the pharynx (T2), at the end of examination (T3), and at the time of awakening (T4) were compared among the three groups of patients. Meanwhile, the total propofol dosage, wake-up time, anaesthetic effect and the occurrence of adverse effects were also recorded in the three groups.Results The changes in HR, MAP and SpO2 in the observation group were better than those in the regular group and control group at all time points during gastroscopy, and compared with the regular group and the control group, the observation group had less total propofol dosage, shorter awakening time, better anaesthesia effect and lower incidence of adverse reactions, which were statistically significant (P < 0.05).Conclusion The scheme of oral lidocaine with low-dose midazolam and other intravenous anaesthetic drugs is shown that it has the advantages of light respiratory depression, stable hemodynamics and better anaesthetic effect in obese patients undergoing painless gastroscopy, which greatly decreases the risk of anaesthesia during painless gastroscopy in obese patients and provides a safe and effective anaesthetic scheme for painless gastroscopy in obese patients. It is worthy to be promoted and applied clinically.