Abstract： Objective To investigate the sedative effect of remazolam on ultrasound-guided medial branch of superior laryngeal nerve block in elderly patients.Methods A total of 60 patients with early-stage laryngeal cancer who were treated in Beijing Tongren Hospital,Capital Medical University from May to September 2023 and underwent laryngoscopic carbon dioxide laser resection were selected.They were divided into midazolam group and remazolam group according to the random number table method,with 30 cases in each group.The patients in the midazolam group were sedated with 0.08 μg/kg sufentanil and 0.02 mg/kg midazolam,and the patients in the remazolam group were sedated with the same dose of sufentanil and 0.04 mg/kg remazolam.The success rate of sedation,sedation onset time,recovery time,mean arterial pressure(MAP),heart rate,pulse oxygen saturation(SpO2),sedation level[evaluated using modified observer's assessment of alert/sedation score(MOAA/S)],patient state index(PSI)at different time points,satisfaction score of patient and anesthesiologist with sedation,and the incidence of adverse events such as bradycardia and hypoxemia during the patient's nerve block period were recorded and compared.Results The success rate of sedation in the remazolam group was significantly higher than that in the midazolam group[83.3％(25/30)vs 53.3％(16/30)],the onset time and recovery time of sedation were significantly shorter than those in midazolam group,and the satisfaction scores of patients and anesthesiologists with sedation were significantly higher than those in the midazolam group(all P＜0.05).The changes of MAP were similar between the two groups during sedation,and the heart rate was more stable than that in the midazolam group.The SpO2 in the remazolam group was lower than that in the midazolam group at 2 min after administration,and those were higher than those in the midazolam group at 6,10,and 15 min after adminis-tration(all P＜0.05).The MOAA/S of the remazolam group was lower than that of the midazolam group at 4,6 and 10 min after administration,while the PSI was higher than that of the midazolam group.At the same time,the PSI of the remazolam group was higher than that of the midazolam group at 15 min after administration(all P＜0.05).There was no significant difference in the incidence of bradycardia,hypoxemia,nausea and vomiting between the remazolam group and the midazolam group during nerve block sedation(all P＞0.05).Conclusion The sedation of remazolam for nerve block in elderly patients with early-stage laryngeal cancer has rapid onset and recovery,and it has better hemodynamic stability,less respiratory depression and better safety than midazolam.