目的 探讨分析右美托咪定联合七氟醚麻醉对老年下肢骨折患者术后认知功能、应激反应及疼痛的影响。方法 选择我院2017年10月至2018年10月骨科收治的68例老年下肢骨折患者为对象展开研究，依据所用麻醉药物的不同将患者均分成两组，分别为观察组和照组，每组34例，对照组采取右美托咪定+丙泊酚进行麻醉，观察组采取右美托咪定+七氟醚进行麻醉，分析两组老年下肢骨折患者术后认知功能、应激反应、不良反应以及疼痛情况。结果 观察组平均动脉压（meanarterialpressure，MAP）、心率（heartrate，H“,”Objective To analyze the effect of DM combined with sevoflurane anesthesia on postoperative cognitive function， stress response and pain in elderly patients with lower limb fracture. Methods A total of 68 elderly patients with lower limb fracture admitted to our hospital from October 2017 to October 2018. The patients were divided into two groups according to different anesthetic drugs used， respectively observation group and control group，with 34 elderly patients with lower limb fracture each.The control group was anesthetized by dextrotomidine + propofol， and the observation group used dextrotomidine + sevoflurane to analyze the postoperative cognitive function， stress response， adverse reactions and pain in the two groups of elderly lower limb fracture patients. Results The stress responses such as heart rate (HR)， mean arterial pressure (MAP)， bispectral index (BIS) and cortisol in the observation group were lower than those in the control group (P＜0.05). There was no significant difference in preoperative cognitive function between the two groups (P＞0.05). The scores of cognitive function at 6 h， 12 h and 24 h in the observation group were higher than those in the control group (P＜0.05). The incidence of complications in the observation group was lower than that in the control group(P＜0.05). There was no significant difference in preoperative pain scores between the two groups (P＞0.05)， the pain scores at 6h， 12 h and 24 h in the observation group were lower than those in the control group (P＜0.05). Conclusion Dexide with sevoflurane anesthesia for elderly patients with lower limb fractures is conducive to the protection of postoperative cognitive function， reduces stress response and pain， further reduces adverse reactions in patients， and has satisfactory anesthesia effect.