不同剂量右美托咪定对老年全膝关节置换手术患者细胞免疫的影响

Effects of different dose of dexmedetomidine on cell-mediated immunity of elderly patients undergoing total knee arthroplasty

目的探讨不同剂量右美托咪定对老年全膝关节置换手术患者细胞免疫的影响。方法将60例择期行膝关节置换手术老年患者随机分为对照组、低剂量组与高剂量组,每组20例。低剂量组与高剂量组分别在蛛网膜下隙阻滞10 min后静脉注射0.33μg/(kg·h)与0.7μg/(kg·h)右美托咪定,对照组给予等量生理盐水。记录患者一般情况、入室心率、血压、术中补液量、失血量;于蛛网膜下隙阻滞后5 min(T_0),术毕5 min(T_1)及术后24 h(T_2)抽取外周血,用流式细胞仪检测淋巴细胞总数、CD3、CD4、CD8、CD4/CD8水平。结果三组患者一般情况、入室心率、血压、术中补液量、失血量及T0时淋巴细胞总数、CD3、CD4、CD8、CD4/CD8水平差异无统计学意义(P>0.05);术毕5 min患者低剂量组及高剂量组淋巴细胞总数和CD4/CD8水平明显高于对照组(P<0.05);术后24 h患者低剂量组及高剂量组淋巴细胞总数、CD3、CD4、CD4/CD8均明显高于对照组(P<0.05),且高剂量组高于低剂量组(P<0.05)。结论使用0.33-0.7μg/(kg·h)右美托咪定,可减轻老年全膝关节置换术患者应激反应,改善免疫功能,值得广泛推广使用。

Objective To explore the effects of different doses of dexmedetomidine（ DEX） on cellular immune function in elderly patients undergoing spinal anesthesia for total knee arthroplasty（ TKA）. Methods Sixty elderly patients undergoing TKA surgery were randomly divided into control group,low-dose group and high-dose group（ n = 20 in each group）. At 10 min after spinal anesthesia,the patients in low-dose group and high-dose group were intravenously given 0. 33 μg/（ kg·h） and 0. 70 μg/（ kg·h） of DEX,respectively,and the patients in control group were given the same amount of normal saline. Blood pressure（ BP）,heart rate（ HR）,volume of fluid input and blood loss were recorded,and flow cytometry was used to detect the amount of lymphocyte,CD3,CD4,CD8,CD4/CD8 levels at T_0（ 5 min after spinal anesthesia）,T_1（ 5 min after operation） and T_2（ 24 h after operation）. Results There was no statistically significant difference among the three groups in the levels of BP,HR,volume of fluid input and blood loss,and lymphocyte,CD3,CD4,CD8,CD4/CD8 at T_0（ P 〉0. 05）. At 5 min after operation,the amount of lymphocyte and CD4/CD8 in low-dose group and high-dose group were all higher than that in control group（ P〈 0. 05）. At 24 h after operation,the amount of lymphocyte,the levels of CD3 and CD4,and CD4/CD8 were all significantly higher than those in control group（ P〈 0. 05）,and they were higher in high-dose group than in low-dose group（ P〈 0. 05）. Conclusion Dexmedetomidine of 0. 33-0. 7 μg/（ kg · h） can reduce the stress,and improve the immune function of elderly patients receiving TKA surgery.