右美托咪定对老年人直肠癌根治术后认知功能的影响

目的观察老年人直肠癌根治术中应用右美托咪啶（DEX）对术后认知功能的影响。方法将60例择期行直肠癌根治术的老年患者按数字表法随机分为2组：DEX组（n=30）和对照组（n=30）。均采用静脉麻醉，将DEX 2 ml（200μg）加入48ml生理盐水中，配成4mg／L的溶液。DEX组在气管插管成功后10min内泵入0．5μg／ks的DEX溶液，继续以0．5μg·kg^-1·h^-1持续泵入至手术结束前30min；对照组在气管插管成功后的10min内泵入0．125ml／kg生理盐水，继以0．125ml·kg^-1·h^-1持续泵入至关腹前。记录2组术前（T0）、术毕（T1）、拔管后5min（T2）、拔管后30min（T3）的收缩压（SBP）、舒张压（DBP）、心率（HR），并记录停全麻药至自主呼吸恢复的时间、至拔管的时间，术前24h、术后24h采用简易精神状态量表（MMSE）评价两组患者认知功能。结果与T0比较，DEX组T1～T3的SBP及HR降低，而对照组T1-T3的SBP升高，差异均有统计学意义（P值均〈0．05）；与对照组比较，DEX组T1-T3的SBP及HR减低，差异均有统计学意义（P值均〈0．01）。DEX组发生术后认知功能障碍（POCD）2例（6．7％），对照组9例（30．0％），两组POCD发生率差异有统计学意义（χ^2=5．46，P〈0．01）。结论DEX能改善老年直肠癌根治术患者的术后认知功能，且使血流动力学更稳定。

Effect of dexmedetomidine on postoperative cognitive function in elderly patients with radical resection of rectal carcinoma

Objective To observe the effect of dexmedetomidine（DEX） on postoperative cognitive function in elderly patients with radical resection of rectal carcinoma with general anesthesia. Methods Sixty elderly patients scheduled for radical resection of rectal carcinoma were randomly divided into 2 groups ： DEX group （n =30） and control group （n =30）. All adopted intravenous anesthesia. The DEX given 2 ml （200 μg） was added 48 ml of saline, dubbed 4 mg/L solution. After the success of the endotracheal intubation, DEX 0.5 μg/kg was infused within 10 minutes in composited DEX group, then DEX was infused at rate of 0.5 μg · kg^-1 · h^-1 until 30 minutes before the end of surgery, while saline 0. 125 ml/kg was infused within 10 minutes in control group, then saline was infused at rate of 0. 125 ml · kg^-1 · h^-1 until 30 minutes before the end of surgery. Systolic pressure （ SBP）, diastolic pressure （ DBP）, heart rate （HR） were recorded before operation （ T0 ） , postoperative （ T1 ）, 5 min after extubation （ T2 ） , 30 min after extubation（ T3 ）. The time from the cessation of drugs to spontaneous breathing recovery time and to extubation time were also recorded. The cognitive function of patients in both groups were evaluated by minimental state examination（MMSE） at pre-operation and 24 h post-operation. Results Compared with T0, SBP and HR in DEX group decreased significantly from T1 to T3 , SBP in control group increased from T1 to T3 （ all P values 〈 0. 05 ） ; compared with control group, SBP and HR in DEX group decreased significantly from T1 to T3 （ all P values 〈 0.01 ）. There were 2 （ 6.7% ） and 9 （ 30. 0% ） cases of post cognitive dysfunction complicated in DEX group and control group, Comparison between the two groups had statistical significance（ χ^2 = 5.46, P 〈 0.01 ）. Conclusions DEX for elderly patients with colorectal cancer radical surgery can improve the postoperative cognitive function, and makes more stable hemodynamies for