Protective effect of dexmedetomidine on cognitive function in elderly patients after operation

doi:10.3760/cma.j.issn.1673-4777.2015.10.014

Abstract：Objective To investigate the protective effect of dexmedetomidine on cognitive function in elderly patients after operation.Methods Totally 120 elderly patients from January 2012 to June 2014 receiving non cardiac surgery were enrolled and randomly divided into control group and dexmedetomidine group (each 60 cases).In both groups,midazolam,sufentanil,etomidate and vecuronium were used for anesthesia induction;remifentanil,propofol and cisatratracurium besilate were intravenously infused during surgery.In dexmedetomidine group,before anesthesia induction,dexmedetomidine was intravenously infused [loading dose of 40 μg,dripping for 10-15 min,then 13 μg/(kg · h),continuing to the end of operation].The doses of remifentanil,propofol and cisatratracurium besilate were recorded;the minimum mental state examination (MMSE) scores before,1,3 and 7 d after operation were assessed;the incidence of postoperative cognitive dysfunction was compared between the two groups.Results No significant fluctuation of blood pressure and severe sinus bradycardia occurred in both groups.The doses of remifentanil,propofol and cisatratracurium besilate in dexmedetomidine group were all significantly lower than those in control group [(1.12 ±0.14) mg vs (1.71 ±0.22) mg,(207 ± 179) mg vs (306 ± 215) mg,(19 ±4) mg vs (26±4) mg] (all P ＜0.05).One day after operation,no significant difference of MMSE score was found between control group and dexmedetomidine group (P ＞ 0.05);3 and 7 days after operation,MMSE score in dexmedetomidine group was higher than that in control group [(27.0 ± 2.3) scores vs (23.0 ± 3.1) scores,(27.3 ± 2.2) scores vs (25.5 ± 2.5) scores] (both P ＜ 0.05).In dexmedetomidine group,the incidence of postoperative cognitive dysfunction was significantly lower than that in control group [6.7％ (4/60) vs 25.0％ (15/60)] (P ＜ 0.05).Conclusion Dexmedetomidine can significantly reduce the amount of narcotic drugs during operation and protect postoperative cognitive function in elderly patients.