Objective:To investigate the preventive effects of hydroxyethyl starch and methoxamine on complications of combined spinal and epidural anesthesia in older adult patients and its influence on hemodynamics.Methods:The clinical data of 120 older adult patients who underwent combined spinal and epidural anesthesia in General Hospital of Armed Police and Marine Police between February 2017 and April 2019 were retrospectively analyzed. The included patients were divided into two groups according to the adverse reactions of drugs used to induce anesthesia: control group (methoxamine injection, n = 55) and observation group (methoxamine + hydroxyethyl starch, n = 65). The changes in hemodynamic index, complications and cognitive function were analyzed in each group. Results:Systolic blood pressures measured at 5, 15 and 30 minutes after anesthesia were (127.53 ± 10.63) mmHg, (119.85 ± 10.86) mmHg, (125.45 ± 10.74) mmHg, respectively in the observation group, which were significantly higher than (118.23 ± 11.32) mmHg, (114.34 ± 10.32) mmHg, (119.01 ± 10.34) mmHg in the control group ( t = 3.66, 2.24, 2.63, all P < 0.05). Diastolic blood pressures measured at 5, 15 and 30 minutes after anesthesia were (76.65 ± 9.07) mmHg, (78.43 ± 9.32) mmHg, (80.19 ± 9.43) mmHg, respectively in the observation group, which were significantly higher than (63.30 ± 9.43) mmHg, (65.98 ± 9.26) mmHg, (70.38 ± 9.17) mmHg in the control group ( t = 6.24, 5.78, 4.55, all P < 0.05). Heart rates measured at 5, 15 and 30 minutes after anesthesia were (73.65 ± 7.67) beats/min, (83.27 ± 9.57) beats/min, (84.10 ± 9.67) beats/min respectively in the observation group, which were significantly higher than (69.76 ± 7.82) beats/min, (64.70 ± 9.38) beats/min, (65.80 ± 9.43) beats/min in the control group ( t = 2.17, 8.46, 8.27, all P < 0.05). The incidences of hypotension and bradycardia in the observation group were 3.08% (2/65) and 3.08% (2/65), respectively, which were significantly lower than 25.45% (14/55) and 21.82% (12/55) in the control group ( χ2 = 12.91, 10.15, both P < 0.05). The Mini Mental State Examination scores measured at 1, 6 and 24 hours after surgery were (26.69 ± 2.51) points, (26.74 ± 2.75) points, and (26.99 ± 2.36) points, respectively in the observation group, which were significantly higher than (23.17 ± 2.41) points, (23.43 ± 2.36) points, and (24.18 ± 2.12) points in the control group ( t = 6.17, 5.55, 5.39, all P < 0.05). Conclusion:Hydroxyethyl starch combined with methoxamine for combined spinal and epidural anesthesia in older adult patients can effectively reduce the hemodynamic fluctuations, decrease the incidences of hypotension and bradycardia, and does not produce a remarkable effect on postoperative cognitive function.